# Simon Jungblut Viola Liebich Maya Bode-Dalby *Editors*

# YOUMARES 9 - The Oceans: Our Research, Our Future

Proceedings of the 2018 conference for YOUng MArine RESearcher in Oldenburg, Germany

YOUMARES 9 - The Oceans: Our Research, Our Future

Sea nettles, genus *Chrysaora*. Freely available at: www.pexels.com/photo/jelly-fish-underwater-115488/

Simon Jungblut • Viola Liebich Maya Bode-Dalby Editors

# YOUMARES 9 - The Oceans: Our Research, Our Future

Proceedings of the 2018 conference for YOUng MArine RESearcher in Oldenburg, Germany

*Editors* Simon Jungblut BreMarE - Bremen Marine Ecology, Marine Zoology, University of Bremen, Bremen, Germany

Viola Liebich Envio Maritime Berlin, Germany

Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research Bremerhaven, Germany

Maya Bode-Dalby BreMarE - Bremen Marine Ecology, Marine Zoology, University of Bremen Bremen, Germany

ISBN 978-3-030-20388-7 ISBN 978-3-030-20389-4 (eBook) https://doi.org/10.1007/978-3-030-20389-4

© The Editor(s) (if applicable) and The Author(s) 2020. This book is an open access publication.

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*To all young marine researchers*

# **Foreword**

YOUMARES 9, a conference from and for YOUng MArine RESearchers, is well-established and an format to present current research topics to early career scientists. This international conference represented a platform for early career scientists in Germany, Europe, and worldwide to build up a scientific network. At large congresses, young scientists often do not have the opportunity to present themselves. YOUMARES 9 was important, giving young researchers a place to discuss their research and engage in discussions on important research questions early in their scientific career.

YOUMARES 9 was organized by master's students and doctoral candidates as a bottom-up conference. The bottom-up concept of YOUMARES 9 was professionalized by a core organizational team and a local team provided by the host. The participants of the organizational team learned to organize conferences, communicate with different stakeholders, and moderate sessions or lead workshops. As a result, the team learned self-confidence and strengthened their key competencies besides their scientific work.

These kinds of conferences are indeed a very good way of supporting young researchers in their starting careers. Young researchers learn to present their work and discuss it with peers and network. To sum up, all participants learn the parts of "how to do research" that take place outside of the lab. During the conference, there is a spirit of curiosity, interest, and energy of young researchers and an open-minded atmosphere.

It was great to be the host of YOUMARES 9 under the theme "The oceans: our research, our future" from 11 to 14 September 2018 at the Carl von Ossietzky University of Oldenburg, ICBM. It was a pleasure to welcome over 300 participants to Oldenburg. Originally, YOUMARES 9 started with a zero budget, but with support from various sponsors from science and industry, it ended up being a prestigious conference.

As a future perspective, such conferences would be an essential link between industry, institutions, and universities to provide young scientists the best possibilities for future careers inside and outside the universities.

These proceedings, which include a peer-reviewed process, are an excellent summary of the research activities of young marine scientists and document the actual challenges in marine and social sciences. This book is the second that was published open access with Springer in the context of YOUMARES.

I congratulate the organizers of YOUMARES 9 for their enthusiasm, creativity, and engagement.

Institute for Chemistry and Biology of the Marine Dr. Ferdinand Esser Environment (ICBM)

**Carl von Ossietzky University of Oldenburg**

Scientific Coordinator of Early Career Researchers (Doctoral Candidates and Postdocs) of the ICBM Oldenburg, March 2019

# **Preface**

This book is the final product of the YOUMARES 9 conference, held from 12 to 14 September 2018 in Oldenburg, Germany. From all areas of marine sciences, bachelor, master, and PhD students were asked to contribute. The oral and poster presentations of this conference represent the most recent research in marine sciences. All presentations were part of a topical session, which were also organized and moderated by early career scientists. Apart from handling the presentation abstracts, all session hosts were given the opportunity to write a review article on a topic of their choice in their area of research. These peer-reviewed articles and the corresponding abstracts are compiled in this book.

The 2018 edition of the YOUMARES series started with an icebreaker event at the State Museum for Nature and Man in the city center of Oldenburg. All participants were welcomed by Prof. Ursula Warnke (State Museum for Nature and Man), Prof. Oliver Zielinski (Institute for Chemistry and Biology of the Marine Environment, ICBM), and Prof. Dieter Hanelt (German Society for Marine Research, DGM). Some introductory games, food, and drinks indeed broke the ice, especially for the people who have not already been part of the YOUMARES family.

The scientific part of the conference was hosted by the Carl von Ossietzky University of Oldenburg and its Institute for Chemistry and Biology of the Marine Environment (ICBM). After some welcome words by Prof. Esther Ruigendijk (University of Oldenburg, Vice President for Early Career Researchers and International Affairs) and Prof. Oliver Zielinski (ICBM), we started a plenary discussion bridging marine sciences with ocean governance and conservation. The vivid discussion was moderated by James G. Hagan (Vrije Universiteit Brussel, VUB). The discussants on the podium were session hosts of the 2018 YOUMARES edition: Meenakshi Poti, Morgan L. McCarthy, Thomas Luypaert, and Liam Lachs (all VUB, experts in the field of environmental conservation), Pradeep A. Singh, and Mara Ort (University of Bremen, representing the field of ocean governance). They were joined by Prof. Zielinski (ICBM, University of Oldenburg) and Dr. Cornelia Nauen (Mundus Maris, Brussels). The opening morning was completed by a keynote talk of Prof. Frank Oliver Glöckner (Max Plank Institute for Marine Microbiology and Jacobs University Bremen) on the "Ocean Sampling Day, an Example for Science 2.0."

One afternoon was reserved for workshops and excursions. Participants could choose from workshops like "How to turn science into a story?," "Publishing in Natural Sciences," and "Knowledge transfer in marine science" as well as guided tours through the city center of Oldenburg or the Botanical Garden of the University Oldenburg and others.

The remaining time was filled with a diverse spectrum of talks and poster presentations of cutting-edge research results obtained by the conference participants. In total, 109 talks and 33 posters were presented in 1 of the 19 sessions.

We hope that this book is a source of knowledge and inspiration to the participants, session hosts, and helpers of YOUMARES 9, as well as to all young marine researchers and to everybody interested in marine research.

Bremen, Germany Maya Bode-Dalby March 2019

Bremen, Germany Simon Jungblut Berlin, Germany Viola Liebich

# **Acknowledgments**

We would like to thank everyone who was helping with the preparation and realization of the conference in Oldenburg. Without the strong support of these volunteers, organizing such a big conference would be impossible. We would like to especially thank Jan Brüwer, Charles Cadier, Muhammad Resa Faisal, Lena Heel, Laura Hennings, Dorothee Hohensee, Patricia Kaiser, Elham Kamyab, Charlotte Kunze, Jonas Letschert, Veloisa Mascarenhas, Lea Oeljeschläger, Nora-Charlotte Pauli, Lena Rölfer, Lukas Ross, Yvonne Schadewell, Paula Senff, Joko Tri Wibowo, Nils Willenbrink, and Mirco Wölfelschneider.

We thank the State Museum Nature and Man and its director, Ursula Warnke, for providing the rooms and supporting the organization of a great icebreaker event and for offering free entrance to their exhibitions for all conference participants.

We are very grateful to the Carl von Ossietzky University of Oldenburg and its Institute for Chemistry and Biology of the Marine Environment (ICBM) for providing the space and rooms for the conference. Very special thanks go to Ferdinand Esser for all the organizational support during the preparation and during the actual conference.

The opening podium discussion received much attention. It was excellently moderated by James G. Hagan, and we would like to thank the discussants: Liam Lachs, Thomas Luypaert, Morgan L. McCarthy, Cornelia Nauen, Mara Ort, Meenakshi Poti, Pradeep A. Singh, and Oliver Zielinski.

Frank-Oliver Glöckner presented a stimulating keynote talk on the "Ocean Sampling Day, an Example for Science 2.0?" for which we thank him very much.

The workshops during the conference were organized by several people to whom we are all grateful: Alexandrine Cheronet, Lydia Gustavs, Daniel Hartmann, Marie Heidenreich, Thijs Janzen, Elham Kamyab, Veloisa Mascarenhas, Cornelia Nauen, Yvonne Schadewell, Tim Schröder, and Nils Willenbrink.

Several partners supported the conference financially, with materials or with special conditions for our conference participants. For any kind of support, we are very grateful to DFG-Schwerpunktprogramm Antarktisforschung, Reederei Laeisz GmbH, Briese Schiffahrts GmbH Forschungsschifffahrt, SubCtech, develogic GmbH subsea systems, Norddeutsche Stiftung für Umwelt und Entwicklung, Stadt Oldenburg, DFG-Sonderforschungsbereich Roseobacter, Institut für Marine Biologie, German Association for Marine Technology (GTM), Bornhöft Meerestechnik, Kraken Power GmbH, Die Flänzburch, and umBAUbar.

Springer Nature provided book vouchers to award the three best oral and the three best poster presentations and one voucher to raffle among all voters.

The Staats- und Universitätsbibliothek Bremen and the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, supported the open-access publication of this conference book.

Thanks go to Alexandrine Cheronet, Judith Terpos, and Springer for their support during the editing and publishing process of this book.

All chapters of this book have been peer-reviewed by internationally renowned scientists. The reviews contributed significantly to the quality of the chapters. We would like to thank all reviewers for their time and their excellent work: Martijn Bart, Kartik Baruah, Thorsten Blenckner, Hans Brumsack, Xochitl Cormon, Michael Fabinyi, Tilmann Harder, Enrique Isla, Annemarie Kramer, Annegret Kuhn, Amy Lusher, Tess Moriarty, Elisabeth Morris-Webb, May-Linn Paulsen, Pamela Rossel Cartes, Chester Sands, Theresa Schwenke, Rapti Siriwardane-de Zoysa, Lydia The, David Thomas, Eva Turicchia, Benjamin Twining, Laura Uusitalo, Jan Verbeek, Ans Vercammen, Benjamin Weigel, and further anonymous reviewers.

We editors are most grateful to all participants, session hosts, and presenters of the conference and to the contributing authors of this book. You all did a great job in presenting and representing your (fields of) research. Without you, YOUMARES 9 would not have been worth to organize.

# **Contents**

# **Contributors**

**Janis Ahrens** Microbiogeochemistry Group, Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Oldenburg, Germany

**Fanny Barz** Thünen-Institute of Baltic Sea Fisheries, Rostock, Germany

**Laura Basconi** Ca Foscari University, Venice, Italy

**Charles Cadier** MER Consortium, UPV, Bilbao, Spain

**Julius Degenhardt** Paleomicrobiology Group, Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Oldenburg, Germany

**Ulrike Dietrich** UiT- The Arctic University of Norway, Tromsø, Norway

**Leon Dlugosch** Biology of Geological Processes Group, Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany

**Hannah S. Earp** Institute of Biology, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, Wales, UK

School of Ocean Sciences, Bangor University, Menai Bridge, Wales, UK

**Mainah Folkers** Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands

**Gustavo Guerrero-Limón** MER Consortium, UPV, Bilbao, Spain

University of Liege, Ulg, Belgium

**James G. Hagan** Faculty of Sciences and Bioengineering Sciences, Department of Biology, Vrije Universiteit Brussel (VUB), Brussels, Belgium

Faculty of Sciences, Department of Biology of Organisms, Université libre de Bruxelles (ULB), Brussels, Belgium

**Brandon T. Hassett** UiT- The Arctic University of Norway, Tromsø, Norway

**Mara E. Heinrichs** Paleomicrobiology Group, Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany

**Elham Kamyab** Institute of Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, Germany

**Matthias Y. Kellermann** Institute of Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, Germany

**Špela Korez** Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany

**Andreas Kunzmann** Leibniz Centre for Tropical Marine Research (ZMT) GmbH, Bremen, Germany

Faculty 02, University of Bremen, Bremen, Germany

**Liam Lachs** Marine Biology, Ecology and Biodiversity, Vrije Universiteit Brussel, Brussel, Belgium

Institute of Oceanography and Environment, Universiti Malaysia Terengganu, Kuala Terengganu, Terengganu, Malaysia

Department of Biology, University of Florence, Sesto Fiorentino, Italy

**Philipp Laeseke** Marine Botany, University of Bremen, Bremen, Germany

**Jonas Letschert** Leibniz Centre for Tropical Marine Research (ZMT), Bremen, Germany

**Arianna Liconti** School of Ocean Sciences, Bangor University, Menai Bridge, Wales, UK

School of Biological and Marine Sciences, Plymouth University, Plymouth, UK

**Sara Doolittle Llanos** Groningen Institute for Evolutionary Life-Sciences GELIFES, University of Groningen, Groningen, The Netherlands

**Thomas Luypaert** Faculty of Sciences and Bioengineering Sciences, Department of Biology, Vrije Universiteit Brussel (VUB), Brussels, Belgium

Faculty of Sciences, Department of Biology of Organisms, Université libre de Bruxelles (ULB), Brussels, Belgium

Faculty of Maths, Physics and Natural Sciences, Department of Biology, Università degli Studi di Firenze (UniFi), Sesto Fiorentino, Italy

**Morgan L. McCarthy** Faculty of Sciences and Bioengineering Sciences, Department of Biology, Vrije Universiteit Brussel (VUB), Brussels, Belgium

Faculty of Sciences, Department of Biology of Organisms, Université libre de Bruxelles (ULB), Brussels, Belgium

Faculty of Maths, Physics and Natural Sciences, Department of Biology, Università degli Studi di Firenze (UniFi), Sesto Fiorentino, Italy

School of Biological Sciences, The University of Queensland (UQ), St. Lucia, Queensland, Australia

**Corinna Mori** Microbiogeochemistry Group, Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany

**Javier Oñate-Casado** Department of Biology, University of Florence, Sesto Fiorentino, Italy Sea Turtle Research Unit (SEATRU), Universiti Malaysia Terengganu, Kuala Terengganu, Terengganu, Malaysia

School of Biological Sciences, University of Queensland, St Lucia, QLD, Australia

**Mara Ort** artec Sustainability Research Center, University of Bremen, Bremen, Germany

INTERCOAST Research Training Group, Center for Marine Environmental Sciences (MARUM), Bremen, Germany

**Lars-Erik Petersen** Institute of Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, Germany

**Santiago E. A. Pineda-Metz** Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Germany

Universität Bremen (Fachbereich 2 Biologie/Chemie), Bremen, Germany

**Meenakshi Poti** Faculty of Sciences and Bioengineering Sciences, Department of Biology, Vrije Universiteit Brussel (VUB), Brussels, Belgium

Faculty of Sciences, Department of Biology of Organisms, Université libre de Bruxelles (ULB), Brussels, Belgium

Faculty of Maths, Physics and Natural Sciences, Department of Biology, Università degli Studi di Firenze (UniFi), Sesto Fiorentino, Italy

School of Marine and Environmental Sciences, University of Malaysia Terengganu (UMT), Terengganu, Kuala Terengganu, Malaysia

Sea Turtle Research Unit (SEATRU), Institute of Oceanography and Environment, Universiti Malaysia Terengganu (UMT), Kuala Terengganu, Malaysia

**Natalie Prinz** Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany Leibniz Centre for Tropical Marine Research (ZMT), Bremen, Germany

**Anja Reckhardt** Microbiogeochemistry Group, Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Oldenburg, Germany

**Titus Rombouts** Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands

**Jessica Schiller** Marine Botany, University of Bremen, Bremen, Germany

**Peter J. Schupp** Institute of Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, Germany

Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB), Oldenburg, Germany

**Kai Schwalfenberg** Marine Sensor Systems Group, Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Wilhelmshaven, Germany

**Heike Schwermer** Institute for Marine Ecosystem and Fisheries Science, Center for Earth System Research and Sustainability, University of Hamburg Germany, Hamburg, Germany

**Stephan L. Seibert** Hydrogeology and Landscape Hydrology Group, Institute for Biology and Environmental Sciences, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany

**Pradeep A. Singh** Faculty of Law, University of Bremen, Bremen, Germany

INTERCOAST Research Training Group, Center for Marine Environmental Sciences (MARUM), Bremen, Germany

**Tobias R. Vonnahme** UiT- The Arctic University of Norway, Tromsø, Norway

**Hannelore Waska** Research Group for Marine Geochemistry (ICBM-MPI Bridging Group), Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Oldenburg, Germany

**Yury Zablotski** Thünen-Institute of Baltic Sea Fisheries, Rostock, Germany

# **About the Editors**

**Dr. Simon Jungblut** Simon Jungblut is a marine ecologist and zoologist. He completed a Bachelor's Degree in Biology and Chemistry at the University of Bremen, Germany, and studied the international program, Erasmus Mundus Master of Science in Marine Biodiversity and Conservation, at the University of Bremen, Germany; the University of Oviedo, Spain; and Ghent University, Belgium. Afterward, he completed a PhD project entitled "Ecology and ecophysiology on invasive and native decapod crabs in the southern North Sea" at the University of Bremen in cooperation with the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, in Bremerhaven and was awarded the Doctoral title in Natural Sciences at the University of Bremen in December 2017.

Since 2015, Simon is actively contributing to the YOUMARES conference series. After hosting some conference sessions, he is the main organizer of the scientific program since 2017.

**Dr. Viola Liebich** Viola Liebich is a biologist from Berlin, who worked on invasive tunicates for her diploma thesis at the Alfred Wegener Institute Sylt. With a PhD scholarship by the International Max Planck Research School for Maritime Affairs, Hamburg, and after her thesis work at the Institute for Hydrobiology and Fisheries Science, Hamburg, and the Royal Netherlands Institute for Sea Research, Texel, Netherlands, she finished her thesis entitled "Invasive Plankton: Implications of and for ballast water management" in 2013.

For 3 years, until 2015, Viola Liebich worked for a project on sustainable brown shrimp fishery and stakeholder communication at the WWF Center for Marine Conservation, Hamburg, and started her voluntary YOUMARES work 1 year later. She is currently working as a selfemployed consultant on marine and maritime management (envio maritime).

**Dr. Maya Bode-Dalby** Maya Bode-Dalby is a marine biologist, who accomplished her Bachelor of Science in Biology at the University of Göttingen, Germany, and her Master of Science in Marine Biology at the University of Bremen, Germany. Thereafter, she completed her PhD thesis entitled "Pelagic biodiversity and ecophysiology of copepods in the eastern Atlantic Ocean: Latitudinal and bathymetric aspects" at the University of Bremen in cooperation with the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, in Bremerhaven and the German Center for Marine Biodiversity Research (DZMB) at the Senckenberg am Meer in Wilhelmshaven. She received her Doctorate in Natural Sciences at the University of Bremen in March 2016.

Maya actively contributes to the YOUMARES conference series as organizer of the scientific program since 2016. Currently, she is working as a scientist at the Marine Zoology Department of the University of Bremen.

# **1 Science for the Future: The Use of Citizen Science in Marine Research and Conservation**

Hannah S. Earp and Arianna Liconti

#### **Abstract**

Over the last decade, significant advances in citizen science have occurred, allowing projects to extend in scope from the ocean floor to the Milky Way and cover almost everything in between. These projects have provided costeffective means to collect extensive data sets covering vast spatio-temporal scales that can be used in scientific research, to develop conservation policy and to promote environmental awareness. This review explores the current status of marine citizen science by examining 120 marine citizen science projects. Trends in geographic locations, focal taxa, participant demographics, tasks undertaken and data directionality (i.e. storage and publication) are highlighted, and the challenges and benefits of citizen science to marine research and conservation are reviewed. Marine citizen science projects act primarily at national levels (53.3%) and mainly focus on coastal ocean environments (49.2%) with chordates as the most popular focus taxa (40%). Some form of methodological training for participants is provided by 64.2% of projects, and the most popular tasks undertaken are field surveys (35.8%) and reporting of opportunistic sightings (34.2%). Data quality and participant motivation are among the most common challenges facing projects, but identified strengths include enhanced marine policy, increased scientific knowledge and environmental stewardship. In con-

H. S. Earp (\*)

Institute of Biology, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, Wales, UK

School of Ocean Sciences, Bangor University, Menai Bridge, Wales, UK

A. Liconti School of Ocean Sciences, Bangor University, Menai Bridge, Wales, UK

clusion, marine citizen science lies at a crossroads of unresolved challenges, demonstrated successes and unrealized potential. However, should the challenges be addressed, the unique capacity of citizen science to broaden the scope of investigations may be the key to the future of marine research and conservation in times of global change and financial hardship.

#### **Keywords**

Volunteer · Public participation · Community-based monitoring · Environmental policy · Ecological surveying

# **1.1 Introduction**

#### **1.1.1 The History of Citizen Science**

Citizen science, often described as amateur participation in scientific research and monitoring, has emerged as a powerful tool and popular activity in recent decades (Cohn 2008; Kullenberg and Kasperowski 2016; Burgess et al. 2017). However, this phenomenon is not new and extends back to before the professionalization of science, whereby most 'scientists' including Benjamin Franklin (1706–1790), Charles Darwin (1809–1888) and Margaret Gatty (1809–1873) made a living in different professions (Silvertown 2009). Yet, despite the evolution of science as a paid profession in the late nineteenth century, amateurs remained involved in many scientific disciplines such as archaeology, astronomy, meteorology and natural history (Silvertown 2009; Haklay 2015). On the verge of the twentieth century, the first 'citizen science project', the National Audubon Society Christmas Bird Count, was established (Cohn 2008; Bonney et al. 2009). It was, however, another 89 years before the first citation of 'citizen science' to describe the collection of rainwater

School of Biological and Marine Sciences, Plymouth University, Plymouth, UK

samples by 225 volunteers as part of a National Audubon Society acid-rain awareness-raising campaign (Kerson 1989), and a further 15 years before its inclusion in the Oxford English Dictionary (OED) in 2014. Today, citizen science is widely defined as 'scientific work undertaken by members of the general public, often in collaboration with or under the direction of professional scientists and scientific institutions' (OED Online 2018a). However, as an evolving discipline, a transition from the primarily contributory paradigm whereby participants mainly collect data, to more collaborative and co-created approaches, where they are involved in additional elements of the scientific process has been observed (Bonney et al. 2009; Wiggins and Crowston 2011; Teleki 2012). Today, some citizen scientists work alone or through community-driven projects, as opposed to directly collaborating with scientists (Bonney et al. 2016a; Cigliano and Ballard 2018). Nevertheless, over the past 20 years, citizen science has boomed, with millions of participants from diverse backgrounds becoming involved in projects that have extended in scope from the seafloor to the Milky Way and covered almost everything in between (Foster-Smith and Evans 2003; Bonney et al. 2016b).

#### **1.1.2 Marine Citizen Science**

Although not as prevalent as their terrestrial counterparts (Roy et al. 2012; Cigliano et al. 2015; Theobald et al. 2015; Garcia-Soto et al. 2017), marine citizen science projects provide a cost-effective means of collecting and analysing extensive data sets across vast spatio-temporal scales, using conventional and new observation and simulation tools (Bonney et al. 2009; Silvertown 2009; Hochachka et al. 2012; Garcia-Soto et al. 2017). Wiggins and Crowston (2011) suggested that citizen science projects fall into five exhaustive groups: (1) action-orientated projects that encourage participation in local issues, for example, collecting and categorizing marine debris (e.g. Marine Conservation Society's Beachwatch available at www.mcsuk.org/beachwatch); (2) conservation projects that promote stewardship and management such as restoring coral reefs (e.g. Rescue a Reef available at sharkresearch.rsmas.miami.edu/donate/ rescue-a-reef); (3) investigation projects that answer a scientific question including monitoring coral reefs (Marshall et al. 2012; Done et al. 2017), cetacean populations (Evans et al. 2008; Tonachella et al. 2012; Bruce et al. 2014; Embling et al. 2015) and invasive species (Delaney et al. 2008); (4) virtual projects that are exclusively ICT-meditated, for example, online photo analysis (e.g. Weddell Seal Count available at www.zooniverse.org/projects/slg0808/weddell-sealcount); and (5) education projects whereby outreach is the primary goal (e.g. the Capturing our Coast 'Beach Babies' survey available at www.capturingourcoast.co.uk/specificinformation/beach-babies).

Thiel et al. (2014) examined 227 peer-reviewed studies involving volunteer-scientist collaborations and showed that developed nations including the United States of America (USA), Australia and the United Kingdom (UK) are hotspots for marine citizen science, with easily accessible areas including intertidal and subtidal regions among the most frequently surveyed environments. However, recent technological developments, often dubbed 'citizen cyberscience', have further elevated the accessibility of citizen science and may in turn alter these trends (Science Communication Unit – University of the West of England 2013). These developments have allowed volunteers from around the world to 'virtually' participate in marine research across international borders and in otherwise inaccessible environments (e.g. the deep sea) from the comfort of home. Examples include Seafloor Explorer (available at www.seafloorexplorer.org), where participants analysed over two million images of the seafloor (~250 m deep) in order to investigate the distribution of commercially important species such as scallops along the northeast United States continental shelf.

# **1.1.3 Citizen Science as a Tool in Research and Conservation**

Despite the broad array of topics, the aims of citizen science projects remain similar: to gather data that answers scientific questions and/or drives policy (Cigliano et al. 2015; Bonney et al. 2016b; Garcia-Soto et al. 2017), to promote environmental awareness and literacy, and to empower citizens and communities (Danielsen et al. 2013; Garcia-Soto et al. 2017). Consequently, it has been suggested that citizen science processes and outcomes warrant acknowledgement as a distinct discipline (Jordan et al. 2015; Burgess et al. 2017; Garcia-Soto et al. 2017). Despite being incorporated into an increasing array of scientific literature, proposals and conference submissions (Cigliano and Ballard 2018), and evolving welltested protocols and data validation techniques, citizen science has yet to be fully embraced by the scientific community, and questions remain surrounding best practices and data quality and/or verification (Cohn 2008; Silvertown 2009; Bonney et al. 2014; Burgess et al. 2017). This review builds on research by Thiel et al. (2014) that demonstrated trends across marine citizen science published in peer-reviewed journal articles, in order to highlight the diversity of current marine citizen science projects. This includes projects that have published their data in peer-reviewed journals, as well as those whose primary aims are to provide data that drives management or to educate and engage the public. 'Voluntourism' projects are excluded from our considerations as they primarily constitute 'voluntary work typically aiming to help others' (OED Online 2018b) as opposed to the 'scientific work' nature of citizen science. The selected marine citizen science projects were examined in order to highlight trends in terms of: geographic locations, focal taxa, participant demographics, tasks undertaken and data directionality (i.e. data publication and storage). Challenges and strengths arising from the review are then presented before suggestions for the future of citizen science in marine research and conservation are made.

# **1.2 Methodology**

#### **1.2.1 Project Selection**

Marine citizen science projects were collated using: (1) Google searches using the keywords 'marine + citizen + science', (2) searches on the citizen science database SciStarter (available at www.scistarter.com) using the keyword 'marine', (3) the Wikipedia citizen science project list (available at www.wikipedia.org/wiki/List\_of\_citizen\_science\_projects), (4) social media searches on Facebook using the keywords 'marine + citizen + science', (5) projects mentioned in reviewed literature and (6) personal knowledge. Project websites were consulted, and a project was included in the review when it had a marine focus and involved citizen scientists. In cases where an organization coordinated multiple citizen science projects, each project was included individually (e.g. The Shark Trust coordinates; The Great Eggcase Hunt, Basking Shark Project and Angling Project: Off The Hook, available at www.sharktrust.org/en/citizen\_science). In cases where a project organized multiple campaign style activities, the project alone was included (e.g. Capturing our Coast available at www. capturingourcoast.co.uk). A total of 120 projects, covering the majority of oceans, their associated flora and fauna, and several conservation issues met the selection criteria (see Appendix 1 for a list of reviewed projects). Data for each project was collected by combining information available from websites, newsletters, databases and email communications. Core data included lead organization, year of establishment, spatial coverage (i.e. international, regional, etc.), location, focus area/taxa, volunteer training requirement (i.e. written instructions, training programs), activity genre (i.e. fieldwork/online) and tasks undertaken (i.e. sightings, image/recording analysis, etc.). When available, information on the number of surveys undertaken by citizen scientists, data validation techniques (i.e. data quality checking), data directionality (i.e. storage location) and number of peer-reviewed scientific publications using the projects data set was also recorded.

# **1.3 Identified Trends Across Marine Citizen Science Projects**

# **1.3.1 Geographic Location**

#### **<IP_ADDRESS> Spatial Coverage**

The reviewed projects occurred across multiple geographical scales, extending from local and regional levels (4.2%) to international and global coverage (42.5%). The majority of projects acted at national levels (53.3%) and spanned nine locations (Fig. 1.1), with the most being located in the USA (43.8%), followed by the UK (27.4%) and Australia (11%). A trend towards greater project abundances in developed

**Fig. 1.1** Number of reviewed marine citizen science projects per location, excluding those operating on international (n = 10) or global (n = 37) scales

H. S. Earp and A. Liconti

nations was observed, with only 6.8% of projects occurring in nations with developing economies (as defined by the United Nations Conference on Trade and Development (UNCTADstat 2018)), for example, Brazil and South Africa. A similar trend was reported by Thiel et al. (2014), although this may be attributed, in part, to the fact that projects incorporated in these reviews were selected based on their journal publications and websites, and consequently projects using other communication strategies to engage with citizen scientists (e.g. local community groups that may be more abundant in developing nations) are excluded.

# **<IP_ADDRESS> Environmental Coverage**

The most commonly investigated environment was the coastal ocean (depth < 200 m) (49.2%), closely followed by easily accessible coastline regions (34.2%) (Fig. 1.2). Although further divisions into zones such as the supralittoral, intertidal, subtidal, continental shelf and oceanic environments (similar to Thiel et al. 2014) were beyond the scope of this review, this information could provide a greater insight into hotspot environments for marine citizen science, as well as those with capacity for development. Interestingly, studies specifically focused on environments known for their roles in supporting ecosystem functions and services, including mangrove and kelp forests, seagrass meadows and wetlands, were limited (5% in total), demonstrating potential opportunities for expansion of citizen science in these environments. An exception was coral reefs that were the focus of investigation in 8.3% of projects, potentially due to their charismatic appeal, exotic location, alongside the relative ease of conducting research involving SCUBA diving in these environments, and the higher volume of visitors as potential citizen science participants (relative to colder oceanic environments).

The deep sea remained the least studied environment with only one project, Digital Fishers (available at www.oceannetworks.ca), focusing their investigations on the organisms inhabiting this remote and often inaccessible region. However, inaccessibility may not be the only reason for the lack of projects concerning this environment, as limited scientific knowledge and expensive technologies may also be factors. Despite large deep-sea video databases being available online (National Oceanic & Atmospheric Administration Ocean Explorer available at www.oceanexplorer.noaa.gov; Monterey Bay Aquarium Research Institute available at www.mbari.org; Japan Agency for Marine-Earth Science & Technology e-library of deep-sea images available at www. godac.jamstec.go.jp), the identification of deep-sea organisms remains complex and thus must be conducted by experts in this field. However, in order to enhance the identification process (i.e. make it quicker and easier), software is currently under development that can automatically identify deep-sea species, and in the case of Digital Fishers, citizen scientists are contributing to the development of this software by 'educating' it to count and identify different taxa (Ocean Networks Canada 2018).

The majority of reviewed projects (25.8%) focused on multiple taxa ('Diverse Taxa') (Table 1.1), through investigations on the intertidal or subtidal or on invasive species and planktonic communities. However, among the most popular individual taxa were the so-called charismatic megafauna, including marine mammals (15%), seabirds (8.3%) and

**Fig. 1.2** Number of reviewed marine citizen science projects per environment, excluding those that focused on multiple environments (e.g. Redmap, available at www.redmap.org.au) (n = 3)

**Table 1.1** Focus taxa of the reviewed marine citizen science projects, excluding those that focused on oceanography or pollution (n = 18). Diverse taxa includes projects focusing intertidal and subtidal flora and fauna, alongside those that focus on multiple invasive or planktonic taxa

sharks/rays (7.5%), which are often considered more newsworthy compared to projects focusing on seaweeds or plankton (Stafford et al. 2010). Surprisingly, sea turtles (also considered charismatic megafauna) were the focus of only one project (Seaturtle.org available at www.seaturtle.org), yet were highly popular among voluntourism projects (e.g. Sea Turtle Conservation available at www.volunteeringsolutions.com, www.frontier.ac.uk and www.gvi.co.uk; SEE Turtles available at www.seeturtles.org). In addition to the popularity of charismatic megafauna, charismatic sessile organisms, such as corals, are frequently investigated by marine citizen science projects, accounting for 6.6% of projects in this review. Despite the popularity of projects involving charismatic taxa, studies focusing on lesser charismatic organisms such as plankton (e.g. FjordPhyto available at www.fjordphyto.wordpress.com; Secchi Disk available at www.secchidisk.org) are growing in popularity, with estimates showing ~110,900 volunteers are engaged in the counting and identification of plankton in the Mediterranean Sea and California currents through Plankton Portal (www. planktonportal.org).

# **1.3.2 Participant Demographics**

#### **<IP_ADDRESS> Participant Recruitment**

At present, there is no quantification of the number of citizen scientists actively involved in scientific research. However, as it often entails limited/no cost, the number is likely to exceed that of voluntourists (estimated at 10 million people per annum by McGehee 2014). Citizen scientists involved in marine research descend from a diverse array of backgrounds and may have no formal training or qualifications in marinerelated subjects (Thiel et al. 2014). Participant recruitment often occurs through collaborations with other established nature organizations including conservation groups and ocean water sport centres. These recreational users of the marine environment, especially SCUBA divers (Martin et al. 2016), often have enhanced interests in marine life and its preservation and are consequently attracted to opportunities whereby they can expand their knowledge base and participate in research (Campbell and Smith 2006; Cohn 2008). More recently, online tools (i.e. project websites and social media) have provided a low-effort method of recruiting both on- and off-site participants. This is partially due to the fact that those with an interest in nature conservation are usually connected with other like-minded people and/or groups online, and consequently a positive loop of information sharing is generated that benefits both citizen science outreach and recruitment.

The majority of reviewed projects are open to participants of any age, although several were noted to exhibit a preference for adult participants (i.e. aged 18 and over); however, this is often due to protocol complexity (see sect. 3.3 for a review). In cases where the protocol requires species identification, adult participants are often designated as final decisionmakers, although younger participants may assist under supervision (e.g. Capturing our Coast available at www.capturingourcoast.co.uk). In the case of projects that involve SCUBA diving, only participants that meet the minimum requirements (e.g. certification and/or experience level) are permitted to partake. However, some variation among minimum requirements is exhibited, for example, to certify as a Reef Check Ecodiver, participants must be comfortable with the use of a mask, snorkel and fins or be a certified SCUBA diver (Reef Check 2018), while the requirements to become a Seasearch Observer include being certified as a PADI Advanced Open Water Diver (or equivalent) and having > 20 dives, of which ≥ 10 should be in temperate waters (Seasearch 2018). Despite some background experience being required in these instances for safety, none of the reviewed projects required participants to have any educational background, as they become trained and therefore specialists in the task required (Hobson 2000). Furthermore, some projects allow participant development to a level whereby they can become project organizers, coordinators, or even lead authors in scientific publications and/or identification guides (see Bowen et al. 2011 for an example of an identification guide authored by citizen scientists). An example includes Seasearch (available at www.seasearch.org.uk) that coordinates general surveys that all participants may undertake, as well as a 'surveyor' level survey for participants that undertake advanced training, and 'specialist projects' created by marine biology experts and experienced volunteers. The latter may involve additional training but in some cases are open to experienced divers that have no previous Seasearch experience (Bunker et al. 2017; Kay and Dipper 2018). This demonstrates how well-designed and long-term projects can satisfy participants from varied backgrounds and allow for significant participant development.

#### **<IP_ADDRESS> Participant Training**

Basic training of participants occurs across the majority of marine citizen science projects and extends from written instructions, to two–three-day training programs, especially in projects involving specific methodological techniques/ protocols (Thiel et al. 2014). Within this review, 77 projects provided some form of participant training, of which 29.9% involved brief instructions, 53.2% involved basic training (i.e. an event where an expert introduced the protocol to be employed) and 16.9% included a ≥ one-day training course. Training of participants involved in projects that use simple protocols (i.e. count or presence/absence surveys) (see sect. 3.3 for a review) primarily occurs through basic written instructions on data sheets and at times video tutorials (Bravo et al. 2009; Ribic et al. 2011). However, in projects that require more complex protocols (i.e. quadrat or transect surveys) and species identification, participants often attend a compulsory ≥ one-day training course, and it was noted that many of these projects often also involve SCUBA diving. Participant capabilities are usually assessed throughout the training, although only six projects explicitly stated that they verified participant capabilities. In addition, complex survey techniques often require additional scientific equipment (e.g. quadrats, transects, diving slates, identification guides, etc.) that are costly, resulting in some projects (e.g. Reef Check California, Mediterranean Sea and Tropical available at www.reefcheck.org) requesting a fee to cover the cost of the training and tools. Although this may limit the project's accessibility, it also ensures training quality and often enhances the recruitment of highly motivated participants. Citizen scientists contributing financially to projects might consider it an investment, and they may in turn be more likely to continue participating. However, this theory has yet to be tested explicitly and represents the scope for future research. Despite the multiple benefits of training, 25.8% of projects required no training, and the majority of these are reliant on incidental sightings (i.e. stranded animals or marine debris) (McGovern et al. 2016). In the case of stranded animals, citizen scientists report the sighting, and professionals are then required for the subsequent removal, identification and autopsy (Avens et al. 2009).

For the most part, the projects considered in this review allow participants to conduct research without professional supervision. Consequently, full explanatory training is key to ensuring the collection of scientifically sound and highquality data (see sect. 3.4 for a review), and the length of the training is somewhat correlated to the complexity of the protocol employed. Some projects further engage with participants through the organization of additional events and courses in order to maintain project engagement and allow for upskilling. An example of this is Capturing our Coast (available at www.capturingourcoast.co.uk) that organizes regular refresher events for trained participants to maintain their survey/identification skills and to enhance data quality, alongside engagement events such as 'Wine and Science' where participants are invited to talks by guest speakers that cover a range of marine science disciplines. Beyond training, many projects communicate with their participants through their websites, newsletters and social media in order to keep them up-to-date with the project progress and encourage further participation. In addition, 'group sourced identification forums' on websites and social media are growing in popularity and may assist in participant engagement and increase the accuracy of the citizen-collected data (Chamberlain 2018). Informal participant feedback has suggested that online engagement strategies are becoming increasingly important components of marine citizen science projects (E. Morris-Webb, personal communication). However, there is currently a lack of systematic reviews on the role of outreach tools in the retention of volunteers highlighting the potential for future research in this area.

#### **1.3.3 Tasks Undertaken**

In order for citizen science projects to investigate the diverse array of habitats and species mentioned previously, a heterogeneous range of methodologies are employed. Each project must use methods that are appropriate to the field of enquiry but that are within the capabilities of the participants recruited (Worthington et al. 2012). Among the most popular are field surveys (35.8%) and reporting of opportunistic sightings (34.2%) (Fig. 1.3), which aligns with the findings of Thiel et al. (2014). Field surveys primarily involve searches for both live (e.g. Reef Check Tropical available at www.reefcheck.org/tropical/overview) and deceased organisms (e.g. Beach COMBERS, available at www.mlml.calstate.edu/ beachcombers), as well as ecological phenomena (e.g. Bleach Patrol available at www.ldeo.columbia.edu/bleachpatrol), during predefined time periods or within predefined areas such as transects and quadrats. Surveys generally require citizen scientists to report findings of abundance or presence/absence, although in some cases, parameters uniquely designed for that project are requested, for example, the reef coloration requested in the CoralWatch bleach-

**Fig. 1.3** Number of reviewed marine citizen science projects per primary tasks undertaken, excluding those that involved several tasks (n = 2)

ing protocol (available at www.coralwatch.org). Other surveys involve more novel methods, such as divers4oceanography (available at www.divers4oceanography.org) that asks SCUBA divers to report ocean temperatures recorded on their dive computers, and Smartfin (available at www. smartfin.org) that has designed a surfboard fin with sensors that allows surfers to collect real-time ocean parameters including temperature, location and wave characteristics (sensors that measure salinity, pH, dissolved oxygen and chlorophyll are under development). Surveying remains a key methodology of marine citizen science projects due to its cost-effectiveness, relative ease of implementation and ability to generate data across large spatio-temporal scales. Opportunistic sightings again allow data to be generated across vast scales and are at times a more time- and effortefficient method compared to quadrat and transect surveys (Wiggins and Crowston 2011; Cox et al. 2012, 2015); although for the most part, they are employed by projects focusing on marine mammals, jellyfish and marine debris (including both field and online projects).

Technological developments have allowed an increasing number of projects to incorporate online citizen scientists to analyse vast data sets of images and recordings (19.1%), often through web portals such as Zooniverse. The popularity of this method lies in the fact that its only limitation is the often time-consuming preparation of the photos prior to being uploaded online. Finally, a combination of advanced technology and that fact that they are often focused on specific target organisms may explain why tagging (i.e. catch, tag and release of organisms) and restoration (i.e. environmental regeneration) were among the least used methodologies (1.6% and 0.8%, respectively) (Fig. 1.3).

#### **1.3.4 Data Directionality**

#### **<IP_ADDRESS> Data Quality**

Citizen science strives to meet the same credibility standards as academic research and industry; however, it is often subject to limited resources and consequently faces trade-offs between data quantity and quality, protocol standardization and discrepancies in skills and expectations of participants and project facilitators/scientists (Robertson et al. 2010; Tulloch et al. 2013). To maintain data quality, some projects statistically compare results reported by citizen scientists to those of professional scientists as a means of data validation (Bell 2007; Worthington et al. 2012; Holt et al. 2013; Bird et al. 2014; Thiel et al. 2014; Earp et al. 2018b). Within this review, 19.2% of projects were found to validate their data in some way, which is much lower than the 55.1% reported by Thiel et al. (2014) in a similar investigation. However, an increasing body of research has shown that data collected by citizen scientists meets, or surpasses accepted quality standards, or detects important ecological trends (Cox et al. 2012; Forrester et al. 2015; Kosmala et al. 2016; Schläppy et al. 2017). In the study of Delaney et al. (2008), the accuracy of volunteers in identifying native and invasive crabs was assessed and found to be between 80 and 95% accurate for school children and even greater for those with a university education, suggesting that demographic variables such as age and educational background may be important drivers of data quality. As a result, choosing a research topic to suit the target participants is key to the success of a citizen science project. In other studies, increasing experience level (Jiguet 2009) and training of participants (Edgar and Stuart-Smith 2009) (see sect. 3.2.2 for a review) were shown to positively correlate with data quality. In other cases, citizen science data has been shown to demonstrate bias or inaccuracies (Courter et al. 2013; Forrester et al. 2015; van der Velde et al. 2017), but this can be minimized in data summaries by examining broader-scale trends (e.g. family level rather than species level) (Fore et al. 2001; Gouraguine et al. 2019) or excluding data from participants that differed substantially to data collected by scientists (Culver et al. 2010). Irrespectively, perceptions on data quality remain a key factor influencing the publication of citizen science data (Schläppy et al. 2017).

#### **<IP_ADDRESS> Data Publication**

In recent years, an increasing number of peer-reviewed journal articles have focused on marine citizen science with many incorporating participant-collected data. This was the case for a minimum of 44 of the 120 reviewed projects that have contributed data to at least 1483 peer-reviewed journal articles. The majority of these publications (54%) were in relation to chordates (Fig. 1.4), of which 70% focused on marine mammals followed by seabirds (15.6%). Interestingly, only 5.2% of chordate publications focused on groups such as sharks and rays. Projects concentrating on diverse taxa were also highly likely to contribute to publications (29.1%), whereas <2% of publications focused on marine pollution.

Despite marine mammals and pollution being the focus of comparable project numbers, the publication frequency of marine mammal data is over 30 times greater than that of marine pollution. This discrepancy may be due to the fact that pollution is a relatively new trend in marine citizen science, whereas the majority of marine mammal projects are well established and commenced prior to 2008. Although the trend towards pollution-based studies has allowed for vast data sets to be generated in seemingly short time periods, the number of investigations (i.e. surveys) was shown to have less of an influence on publication frequency compared to project duration (Fig. 1.5a). Project durations vary from days to decades (Thiel et al. 2014), and of the projects that state their start date (n = 103), the greatest percentage (24.3%) are currently between 2 and 5 years in duration. Despite a limited correlation between project duration and publication frequency (Fig. 1.5b), short projects have a demonstrated capacity to be published, for example, in the 2-day 'bioblitz' undertaken by Cohen et al. (2011) in Sitka (Alaska), where citizen scientists collected data that confirmed a 1000 km northward extension of the colonial tunicate *Didemnum vexillum* (Sundlov et al. 2016).

#### **<IP_ADDRESS> Policy Development**

It is important to note that peer-reviewed journal articles are not the only outlet for marine citizen science data, and in some cases, especially in terms of marine pollution, the data collected is more valuable for aspects such as informing policy or driving management (Newman et al. 2015; Burgess et al. 2017). Marine legislation is often underpinned by evidence from large data sets, and citizen science provides a cost-effective method for their generation (Crabbe 2012; Hyder et al. 2015). The importance of marine citizen science in delivering evidence to support decision-making in marine

**Fig. 1.4** Number of peer-reviewed journal articles (n = 1483) per focus taxa published by reviewed marine citizen science projects, excluding those that focus on oceanography or pollution (n = 18)

**Fig. 1.5** Number of peer-reviewed journal articles published by reviewed marine citizen science projects (n = 1483) vs. number of project investigations (i.e. surveys) (**a**) and project duration (**b**)

**Table 1.2** The primary policy area underpinned by reviewed marine citizen science projects and the total number of publications generated by projects in each of these areas

legislation was reviewed by Hyder et al. (2015), who classified four marine policy areas (biodiversity, physical environment, pollution and resource management) in which citizen science had played a valuable role. Within our review, the majority of projects (79.2%) were found to provide evidence underpinning biodiversity conservation policies (Table 1.2). Within this policy area, > 40% of projects investigated questions regarding species distribution, which was supported by findings from a study by Hyder et al. (2015). Other popular policy areas underpinned by the reviewed projects were: biological research (25.8%), marine debris surveying (8.3%), marine protected area (MPA) designation (5.8%) and invasive species tracking (5%) (Table 1.2).

#### **<IP_ADDRESS> Data Storage**

Although the use of citizen science data varies, projects are encouraged to make their data publicly accessible, yet in this review, less than 10% of projects stored their data on a repository (e.g. NBN Atlas available at www.nbnatlas.org). In particular, all species survey data from reviewed citizen science projects in the UK is stored on NBN Atlas, which is accessible to the public and government for a range of purposes, although some data limitations exist regarding commercially sensitive/overexploited species. The majority of reviewed projects instead made their data available through the project website (50.8%), although 40% of projects kept their data private or failed to disclose its location.

#### **<IP_ADDRESS>.1 Species Distribution**

The long-term observational data sets generated by citizen science projects, which often extend beyond timescales of standard research programs (i.e. two-three years), are also of exceptional value in addressing questions regarding the spatio-temporal distribution of marine organisms (Ponti et al. 2011b; Mieszkowska et al. 2014). More recently these data sets have become important in assessing the response of organisms to climate change (Southward et al. 2005; Mieszkowska et al. 2014). Climate change can induce socalled shifts in marine species distributions, either towards more favourable seawater temperatures or because of trophic mismatches resulting from changes in prey phenology (Visser and Both 2005; Cheung et al. 2009). Mieszkowska et al. (2014) demonstrated some of the fastest geographic range shifts in marine species in 50 years using citizen science data collected as part of the Marine Biodiversity and Climate Change (MarClim) project. Lusitanian species, including *Phorcus* (previously *Osilinus*) *lineatus* and *Steromphala* (previously *Gibbula*) *umbilicalis* (topshells), *Chthamalus montagui* and *Perforatus perforatus* (barnacles), as well as the limpet *Patella depressa* and the macroalga *Bifurcaria bifurcata*, extended their range poleward, whilst Boreal species, such as the barnacle *Semibalanus balanoides* and the kelp *Alaria esculenta*, were shown to be important indicator species that fluctuate in abundance in response to periods of warming and cooling (Mieszkowska et al. 2014). Although only two projects in this review investigated physical components of climate change (i.e. changes in temperatures, pH and storm frequency), numerous projects (35.8%) addressed questions regarding species distributions with several of these providing information important for climate change studies (e.g. information on coral bleaching that results from climatic change).

#### **<IP_ADDRESS>.2 Invasive Non-Native Species**

Marine citizen science is not only a powerful tool in monitoring the distribution of native species but also the arrival and encroachment of invasive non-native species (Delaney et al. 2008; Parr and Sewell 2017), whose impacts on native ecosystems remain poorly understood (Ruiz et al. 1997). These species can go undetected for extended periods of time (i.e. years) (Geller et al. 1997; Lohrer 2001), meaning their subsequent eradication may be difficult, in part because of large population sizes (Bax et al. 2001). Consequently, monitoring for invasive species is of primary importance so that early eradication can be conducted (Delaney et al. 2008). In the USA, the Citizen Science Initiative: Marine Invasive Species Monitoring Organization (www.InvasiveTracers.com) used 190 groups of participants to survey 52 sites for a species of introduced Asian shore crab (*Hemigrapsus sanguineus*), previously known only to be present in Moores Harbour. They reported a notable expansion of the range of *H. sanguineus*, with one specimen being reported 60 km northeast of Moores Harbour (Delaney et al. 2008). Some invasive species are not only detrimental to native ecosystems, but also to local economies, for example, the carpet sea squirt (*Didemnum vexillum*), which was discovered in the UK for the first time by citizen scientists in a study conducted by Cohen et al. (2011). *D. vexillum* is detrimental to shellfish aquaculture with high abundances resulting in increased labour costs and reduced product value (Watson et al. 2009; Adams et al. 2011). Knowing the origin and arrival location of invasive species is very important to model their potential dispersion pathways, allow for early detection and in turn limit further colonization of new areas (Ricciardi et al. 2000). The spatio-temporal scale at which citizen science operates is therefore of exceptional value to invasive species monitoring and benefits both scientific research and industry. Although several of the reviewed projects (e.g. Capturing our Coast available at www.capturingourcoast. co.uk, Seasearch available at www.seasearch.org.uk and Reef Check Mediterranean Sea available at www.reefcheckmed.org) have trained volunteers to report sightings of non-native species, they were the primary focus of only 5% of reviewed projects (Table 1.2), therefore demonstrating scope for significant expansion of marine citizen science in this area.

#### **<IP_ADDRESS>.3 Marine Debris**

As part of an action to tackle a widespread and growing issue, citizen scientists are helping to investigate marine debris by contributing to vast global data sets that form the basis of both political decisions and conservation policies (Ryan et al. 2009; Eriksen et al. 2014; Hidalgo-Ruz and Thiel 2013, 2015; Nelms et al. 2017). Although this policy area was underpinned by only 8.3% of projects within this review (Table 1.2), it has grown considerably in the past decade, with more citizens sharing responsibility for the issue and contributing to projects aiming to provide solutions (Hidalgo-Ruz and Thiel 2015; Nelms et al. 2017). These projects often involve simple beach clean-ups that provide information on the distribution and abundance of marine debris items (Ribic 1998; Martin 2013). Because of the simplicity of the protocols, several citizen science projects underpinning different areas of policy (i.e. biodiversity policies such as species distribution and stranding) have organized events to tackle marine debris issues and contributed to litter recording databases. In the UK, citizen scientists reported and collected over 10,866 plastic bottles as part of the Marine Conservation Society Wild Bottle Sighting campaign (www.mcsuk.org/bottlesightings). The awareness raised and evidence collected through this, and other similar campaigns (OSPAR 2010; Van Franeker et al. 2011), were key to the decision of the UK government to develop a Deposit Return System for plastic bottles and aluminium cans as part of a plan to eliminate single-use plastic by 2042 (official press release available at www.gov.uk/government/ news/deposit-return-scheme-in-fight-against-plastic).

#### **<IP_ADDRESS>.4 Marine Protected Areas**

One method to protect and promote biodiversity is the designation of marine protected areas (MPAs) and Marine Conservation Zones (MCZs); however to do this, patterns of species distributions across vast spatio-temporal scales (such as those covered by citizen science/scientists) are required (Dickinson et al. 2010; Cerrano et al. 2012; Crabbe 2012; Markantonatou et al. 2013; Branchini et al. 2015; Jarvis et al. 2015; Cerrano et al. 2017). Additionally, marine citizen science is also an effective tool for monitoring MPAs that is essential to support adequate management and to fulfil the requirements of the European Marine Strategy Framework Directive (Directive 2008/56/EC) (Ponti et al. 2011a; Cerrano et al. 2017; Turicchia et al. 2017). This review found that 5.8% of projects provided data that underpins MPA designation and/or monitoring (Table 1.2). Despite this low percentage, the majority of these projects were found to operate over extensive geographical ranges (e.g. Reef Check available at www.reefcheck.org; eOcean available at www.eoceans.co; SubseaObservers available at www.subseaobservers.com). Since its establishment in 1996, Reef Check data has contributed to the establishment and monitoring of several MPAs in regions with limited funding for conservation policies (Cerrano et al. 2012), and in the UK, the Seasearch data set that extends back to 1984 has contributed to the designation of 38 MCZs and several other MPAs including Lamlash Bay No-Take Zone (Seasearch 2018).

# **1.4 Challenges and Strengths of Marine Citizen Science**

### **1.4.1 Challenges**

The rapid expansion of marine citizen science, coupled with advancing possibilities and limited funding means, at present, limited guidelines for good practice are in place, and instead many facilitators are learning on the job (Silvertown 2009). Consequently, many projects face challenges, usually in the form of participant motivation and/or data issues.

#### **<IP_ADDRESS> Participant Motivation**

At the organizational level, motivation is one of the most commonly referenced challenges facing citizen science (Conrad and Daoust 2008; Conrad and Hilchey 2011; Rotman et al. 2012), and it comes in two forms: (1) motivating outsiders to sign-up and begin participating and (2) motivating participants to continue or expand their participation (Prestopnik and Crowston 2011; Rotman et al. 2012). To motivate participants to sign up, some projects focus specifically on either charismatic organisms (Bear 2016; Garcia-Soto et al. 2017) or accessible environments (Garcia-Soto et al. 2017), or incorporate an activity (e.g. SCUBA diving) into the protocol to engage participants who readily participate in this activity already (e.g. Seasearch available at www. seasearch.org.uk). However, these strategies generate issues including a data bias towards charismatic species and accessible nearshore environments that may be of limited ecological/scientific relevance, or if SCUBA diving is required, the project may become cost and/or experience prohibitive to certain participants. An often-unaddressed issue of citizen science is accessibility, especially for participants with impairments. For the most part, projects involve either a physical task in a somewhat hazardous (i.e. slippy) environment, a highly skilful and intense activity (e.g. SCUBA diving), or recording on small data sheets. Consequently, participants with impairments may be limited to online marine citizen science projects, unless a protocol can be adapted to suit their needs.

Motivating participants to continue or expand their participation is often a greater challenge, especially when the project involves reporting 'zero data', which may be of significant scientific importance, but it is often disengaging and might result in declines in participation (Bear 2016). One solution to maintain engagement that is also used to motivate sign-ups and initial participation is gamification (Prestopnik and Crowston 2011) and/or incentivization of the protocol (e.g. the 'Top Trumps' format of the Capturing our Coast 'Beach Babies' survey, available at www.capturingourcoast. co.uk/specific-information/beach-babies). For participants, the more fun, or the greater the benefit they receive from completing the work, the more likely they are to participate (Prestopnik and Crowston 2011). In addition, feedback to participants is of exceptional importance (Bonney et al. 2009; Silvertown 2009) and has been shown to increase and/ or maintain participation by demonstrating the value of their contribution (Rotman et al. 2012). Research from Thiel et al. (2014) supports this view, stating that public recognition of participant effort is a significant motivator for participation but that factors including personal satisfaction (i.e. wellbeing impact of developing social connections and being outdoors) and development of a skill base (i.e. greater understanding of the scientific processes) are also important motivators.

#### **<IP_ADDRESS> Data Concerns**

Another obstacle facing citizen science is perceptions regarding data quality (see sect. 3.4 for a review), despite several studies demonstrating that the data meets accepted quality standards (Cox et al. 2012; Forrester et al. 2015; Kosmala et al. 2016; Schläppy et al. 2017). These concerns often relate but are not limited to a lack of attention to project design and standardized data verification methods, limited participant training and sampling biases (Conrad and Hilchey 2011; Burgess et al. 2017). Riesch and Potter (2014) postulated that a lack of use of citizen science data in academia may stem from the belief of some scientists that the data would not be well received by their peers. In terms of policy development, the United States Congress excluded volunteer collected data from their National Biological Survey over concerns that it would be biased based on environmentalist agendas (Root and Alpert 1994). To address the issue of data perceptions, Burgess et al. (2017) suggest greater transparency and availability of methods and data attributes that will hopefully result from the generation of good practice guidelines and toolkits for citizen science (Silvertown 2009). However, despite the shortcomings, many benefits of marine citizen science have been documented. For this reason, the development of a standard 'impact assessment', to assess survey and data verification methods, as well as scientific and socio-psychological benefits would be highly beneficial to marine citizen science projects.

#### **1.4.2 Strengths**

The strengths of citizen science have been demonstrated to extend across scientific, social and economic boundaries, as well as underpinning several areas of marine policy (see sect. <IP_ADDRESS>) (Delaney et al. 2008; Crabbe 2012; Mieszkowska et al. 2014; Hidalgo-Ruz and Thiel 2015; Hyder et al. 2015; Turicchia et al. 2015; Parr and Sewell 2017).

#### **<IP_ADDRESS> The Many Eyes Hypothesis**

The 'many eyes hypothesis' has been used to describe the efficiency of marine citizen science in generating data across vast spatio-temporal scales and across multiple taxa (Hochachka et al. 1999; Dickinson et al. 2012; Thomas et al. 2017). This hypothesis, in the case of animal aggregations, shows a larger group size has extended individual feeding times and an increased likelihood of detecting predators compared to smaller groups (Lima 1995). When applied to citizen science, it demonstrates that a network of citizen scientists with clearly defined protocols and realistic survey aims is capable of surveying vast areas (Ponti et al. 2011b; Cerrano et al. 2012, 2017), which increases the chances of detection of a species/phenomenon, increases replication rates and decreases individual effort (Hochachka et al. 1999; Thomas et al. 2017). This 'many eyes' effect has allowed citizen science to benefit landscape ecology and macroecology research by covering extensive spatio-temporal scales (Parmesan and Yohe 2003; Southward et al. 2005; Dickinson et al. 2010, 2012; Mieszkowska et al. 2014; Schläppy et al. 2017), alongside providing an efficient means for detecting species with low abundances (e.g. rare or invasive species) (Delaney et al. 2008; Dickinson et al. 2010, 2012).

#### **<IP_ADDRESS> Marine Stewardship**

Appropriately designed projects not only have the potential to broaden the scope of marine research and policy but also reconnect participants with nature that in turn increases their awareness of the current status of the marine realm and the threats it faces (Brightsmith et al. 2008; Dickinson et al. 2010; Koss and Kingsley 2010; Garcia-Soto et al. 2017; Cerrano et al. 2017; Schläppy et al. 2017; Turicchia et al. 2017). Through marine citizen science projects, participants may observe the impact of anthropogenic activities on marine environments, which may promote a sense of ownership and drive behavioural changes towards more sustainable actions (Branchini et al. 2015; Cerrano et al. 2017). This increased awareness may then be used to promote marine stewardship, and in many cases, participants often become advocates of marine conservation (Dickinson et al. 2010; Cerrano et al. 2017; Garcia-Soto et al. 2017). The enhanced ocean literacy, resulting from participating in marine citizen science projects, combined with exposure to science through other mediums (e.g. television documentaries and news articles) (Thiel et al. 2014) may also lead to greater support for scientific advances and policy, as opposition often results from a lack of understanding of the underlying science (Schläppy et al. 2017). This environmental stewardship also forms the basis of compliance with marine management policies such as MPAs and can indirectly enhance their efficiency (Evans et al. 2008; McKinley and Fletcher 2012).

# **1.5 Summary**

At present, marine citizen science is at a crossroads of demonstrated sucesses, unresolved challenges and unrealized potential (Burgess et al. 2017). To resolve these challenges, and fulfill its potential, citizen science practitioners must be willing to acknowledge project shortcomings and work together to align objectives and methodologies that ensure the generation of high-quality data sets (Burgess et al. 2017). In addition, the accessibility and feasibility of the project to a diverse array of participants, as well as methods of disseminating project findings to participants, must be considered. Overall however, the projects investigated within this review demonstrated positive outcomes of collaborations between members of the public and scientists. Citizen scientists become specialized in the protocols used and in turn provide quality data that increase the spatio-temporal coverage of marine research (Thiel et al. 2014).

With our oceans and coasts in peril due to changing climatic conditions and increasing anthropogenic activities (Cigliano et al. 2015, Earp et al. 2018a), marine citizen science provides a unique platform to discover, innovate and address global challenges (i.e. species shifts and marine debris) for which data is significantly lacking (Bear 2016). As marine citizen science comes of age, although not panacea, if it successfully keeps pace with the changing contexts of marine ecological research, conservation needs and stakeholder interests, its capacity to increase ocean literacy may aid the development of culturally and politically feasible solutions for a more sustainable future (McKinley et al. 2017; Schläppy et al. 2017). With this in mind, it can be summarized that the current benefits of marine citizen science outweigh the challenges, and there is significant scope for the development and incorporation of 'science by the people' into marine research and conservation projects (Silvertown 2009).

**Acknowledgements** The authors are grateful for the constructive input of Dr. Siobhan Vye, Ms. Natalie Prinz and three reviewers, Dr. Ans Vercammen, Dr. Eva Turicchia and Ms. Elisabeth Morris-Webb that greatly improved the manuscript. We would also like to share our gratitude to the YOUMARES 9 committee for the opportunity to research a topic that is close to both our academic and personal experiences. Finally, our appreciation and recognition goes to all professional and citizen scientists involved in the reviewed projects for their outstanding work and commitment in making citizen science the science of the future.

# **Appendix**

This article is related to the YOUMARES 9 conference session no. 1: "Could citizen scientists and voluntourists be the future for marine research and conservation?" The original Call for Abstracts and the abstracts of the presentations within this session can be found in the Appendix "Conference Sessions and Abstracts", Chapter "1 Could citizen scientists and voluntourists be the future for marine research and conservation?", of this book.

# **Supplementary Material**

**Table 1.A1** Name and website of the 120 marine citizen science projects reviewed in this manuscript

#### **Table 1.A1** (continued)

**Table 1.A1** (continued)

All websites last accessed 24 June 2019 by the authors

# **References**

change scenarios. Fish Fish 10(3):235–251. https://doi. org/10.1111/j.1467-2979.2008.00315.x

Commission DG Environment, December 2013. Available at: www. ec.europa.eu/science-environment-policy

**Open Access** This chapter is licensed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons. org/licenses/by/4.0/), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made.

The images or other third party material in this chapter are included in the chapter's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the chapter's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.

Heike Schwermer, Fanny Barz, and Yury Zablotski

© The Author(s) 2020 21

#### **Abstract**

Stakeholder participation is a fundamental component of many states' and local agencies' fisheries legislations worldwide. The European Common Fisheries Policy (CFP), as one example, increasingly adopted a holistic approach to managing marine living resources. An important component of such an ecosystem-based management approach is the consideration of knowledge, values, needs and social interactions of stakeholders in decision-making processes. However, despite that stakeholder participation is a widely used term, a great variety of definitions exist, which often cause misunderstanding. Stakeholder participation is often used as part of conducting research on stakeholders but not in the context of their participation in resource management. Here, we present the results of a comprehensive literature review on the topic *stakeholder participation* in coastal and marine fisheries. We identified 286 scientific publications in *Web of Science* of which 50 were relevant for our research questions. Publications were analysed regarding (i) definition of stakeholder participation, (ii) analysis of participating stakeholders, (iii) applied participatory methods and (iv) intention for participation. Stakeholder types addressed in the publications included, e.g. fishery (fishers and direct representatives, N = 48), politics (policymakers and managers, N = 31), science (N = 25) and environmental nongovernmental organizations (eNGOs, N = 24). In total, 24 publications labelled their studies as stakeholder participation, while stakeholders were only used as a study object. We conclude that improving science and the practice of including stakeholders in the management of

H. Schwermer (\*)

S. Jungblut et al. (eds.), *YOUMARES 9 - The Oceans: Our Research, Our Future*,

F. Barz · Y. Zablotski Thünen-Institute of Baltic Sea Fisheries, Rostock, Germany

https://doi.org/10.1007/978-3-030-20389-4\_2

coastal and marine fisheries requires definitions of who is considered a stakeholder and the form of participation applied.

#### **Keywords**

Case survey method · Stakeholder types · Participatory methods · Multiple Correspondence Analysis

# **2.1 Introduction**

Stakeholder participation is a fundamental component of many states´ and local agencies' fisheries legislations worldwide (NOAA 2015). As an example, the Common Fisheries Policy of the European Union increasingly adopted a holistic approach to managing marine living resources (Commission of the European Communities 2013). An important component of such an ecosystem-based management (EBM) approach is the consideration of knowledge, values, needs and social interactions of resource users and other interest groups in decision-making processes (Long et al. 2015). Aanesen et al. (2014) established that in the case of fisheries management, this implies having access to local ecological knowledge of fishers to complement scientific data which is often very limited. Furthermore, involving stakeholders is expected to increase the legitimacy of the management by creating understanding and support among the stakeholders for management measures such as new regulations (Aanesen et al. 2014). Moreover, stakeholders represent varying preferences about a resource and, therefore, ideally enable processes to reach sustainable management on different levels, such as ecological and social. But the terms 'stakeholder' and 'participation' have become 'buzz words' in environmental management (Voinov and Bousquet 2010). Deviating definitions and explanations of both terms occur, and it is often unclear what is actually meant by these concepts.

**2**

**A Literature Review on Stakeholder Participation in Coastal and Marine Fisheries**

Institute for Marine Ecosystem and Fisheries Science, Center for Earth System Research and Sustainability, University of Hamburg Germany, Hamburg, Germany e-mail<EMAIL_ADDRESS>
We here reviewed worldwide case studies to investigate how stakeholder participation is applied in research projects concerning coastal and marine fisheries. The literature review creates an overview of current meanings and methods applied in this research field. The aim of our study is to highlight and to critically discuss the application of the term stakeholder participation and the significance of these findings for future research projects in general and particular in the field of coastal and marine fisheries. In our study, we developed and applied nine questions to review and analyse relevant publications. First, we investigated the publications regarding the use of the term *stakeholder*. Here, we focused on term definition, approach of analysing stakeholders as well as on the stakeholder types involved in the case study. Subsequently, we reviewed the publications in relation to the term *participation*, again first focusing on term definition, methods used related to the participation of stakeholders, description and intention for participation. Finally, we analysed all publications to evaluate whether the publications used participation as a tool for researching stakeholders (research tool) or for conducting true stakeholder participation (participation tool).

Our study revealed that only few publications in the research field of coastal and marine fisheries clearly defined the terms stakeholder and participation. Furthermore, the majority of publications labelled their studies as stakeholder participation, while stakeholders were only used as a study object. We conclude that improving the science and the practice of including stakeholders in the management of coastal and marine fisheries requires definitions of who is considered a stakeholder and the form of participation applied.

#### H. Schwermer et al.

# **2.2 Material and Methods**

We conducted a systematic literature review using the *case survey method* (Newig and Fritsch 2009), i.e. one article represented one analysis unit. Here, qualitative studies were transformed into semi-quantitative data, applying a coding scheme and expert judgements by multiple coders. The case survey method allowed us to synthesize case-based knowledge using at least two coders. We translated our research steps (RS) into a research protocol, adapted after Brandt et al. (2013), making RS repeatable and transparent. Our study included five working steps (WS): data gathering (WS 1), data screening (WS 2), data cleaning (WS 3), paper reviews (WS 4) and a statistical analysis of the collected data (WS 5) (Table 2.1).

In WS 1 we derived relevant publications from the *Web of Science* (WoS; www.isiknowledge.com), an extensive and multidisciplinary database covering a large number of scientific journals, books and proceedings in the field of natural science and technique, arts, humanities and social sciences (ETH Zürich 2018). We extracted articles published within the period from 2000 to 2018, considering the establishment of participation in (environmental) decision-making processes as a democratic right by the United Nations Economic Commission for Europe's 1998 Arhus Convention and an increased use (Reed 2008). To ensure an establishment in research publications, we started the review two years later. Publications were collected by using the basic search routine in the WoS (date of search: 16 May 2018) applying the following keyword strings: (i) stakeholder – participation – fishery, (ii) stakeholder – involvement – fishery and

**Table 2.1** The five working steps (WS) of our literature review on stakeholder participation in the field of coastal and marine fisheries consisted of data gathering, data screening, data cleaning, paper review and statistical analysis. The review procedure and the results are presented for each WS

(iii) stakeholder – engagement – fishery. We additionally used the string 'fisheries' instead of 'fishery'.

In WS 2 we screened all publications derived in WS 1; we only further considered the publications that included all three keywords stakeholder, participation/involvement/ engagement and fishery in (i) the title, (ii) the abstract or (iii) the keywords. We also included publications that either used the noun, the verb, i.e. to fish, to participate/ involve/engage, or the adverb of the keyword, like 'fishing community'.

For the data cleaning (WS 3), we used an inductive approach to identify key issues of selected publications based on two characteristics:

We here described policy as a set of rules or an established framework; management was defined by general environmental management approaches (e.g. ecosystem-based management (EBM), coastal management) or explicit management measures.

In WS 3 we excluded publications with focus on freshwater or estuarine ecosystems, recreational fisheries and marine protected areas. In addition, we discarded publications with focus on coastal management and EBM as well as publications looking at political frameworks (CFP, MSFD). All remaining publications focused on coastal and marine fisheries.

We further only analysed publications that presented a case study; in WS 3 we discarded studies that represented a meta-analysis or theoretical participation framework description. We here defined a case study as "[…], analyses of persons, events, decisions, periods, projects, policies, institutions, or other systems that are studied holistically by one or more methods. The case that is the subject of the inquiry will be an instance of a class of phenomena that provides an analytical frame — an object — within which the study is conducted and which the case illuminates and explicates" (Thomas 2011). For an evaluation of the regional distribution, we also extracted the continent where the case study has been conducted.

In WS 4 we analysed the content of the finally selected papers applying a mixed-method approach. We evaluated the publications based on 9s questions, investigating the terms *stakeholder* (questions 1–4) and *participation* (questions 5–8) first separately and subsequently in combination (question 9). The list of questions is shown in Table 2.2. We applied a quantitative approach to investigate naming and definition of both terms (questions 1–8, Table 2.2). Furthermore, we applied an inductive approach to generate categories for analysing derived data to elicit which type of stakeholders, participation tools and intention categories for participation were part of the research projects (questions 2, 6 and 8, Table 2.2) (Mayring 1988). Eight *stakeholder types* were distinguished in our analysis, i.e. science, politics, environmental non-governmental organizations (eNGOs), fisheries, fishery-related industry, recreational fisheries, public and others. Although we excluded publications that focus on recreational fisheries, this stakeholder type was part of the case studies focusing on coastal and marine fisheries and, therefore, was included as one stakeholder type within our analysis. The category 'others' included stakeholders that did not fit into any of the other categories but have been explicitly mentioned separately from them. We similarly analysed questions 6 and 8. Here, we distinguished between 11 *participatory methods*, i.e. workshop, interview, meeting, discussion, survey, questionnaire, modelling, coordination, mapping, presentation and conversation, and 10 *intention categories*, i.e. analysis, assessment, definition, description, development, establishment, evaluation, feedback, identification and improvement. Related to the description in the publications, we distinguished between active and passive participatory methods: active ones describing methods that directly involved stakeholders in decision-making processes; passive participatory methods had been described to support the participatory process but not to involve the stakeholders

**Table 2.2** Nine questions used to review the identified case studies in coastal and marine fisheries management. The terms stakeholder (questions 1–4) and participation (questions 5–8) were investigated separately and in combination, i.e. stakeholder participation (question 9)

**Fig. 2.1** Number of research publications published from 2000 to 2018 dealing with case studies in coastal and marine fisheries as found by Web of Science (keywords: stakeholder, participation/ engagement/involvement, fishery) as of May 2018. Black line represents the linear regression with 95% confidence intervals; the grey area indicates the confidence band (R2 = 0.6045, p = 0.000645)

in research or management (decision-making processes). Participatory methods and intention categories were extracted according to the mention in the publications. Related to the participatory methods, we also determined whether preparatory work was done using an inductive approach.

Eventually, we investigated whether (i) the case studies conducted participation to gather knowledge from stakeholders but without engaging these stakeholders in a decision-making process (*research tool*) or (ii) stakeholders had a direct influence on data interpretation and decisionmaking processes (*participation tool*).

In the final working step (WS 5 – statistical analysis), we used Multiple Correspondence Analysis (MCA) to explore the relationships between stakeholder types. MCA is able to uncover correlations (i.e. similarities, grouping) in otherwise inconvenient survey data (Higgs 1991) and was designed to apply on multiple binary (or nominal) variables (e.g. our categories stakeholder 'science': absent = 0, present = 1; stakeholder 'public': absent = 0, present = 1), all of which had the same status (Abdi and Valentin 2007). MCA explores the patterns in data by measuring the geometric proximity between stakeholder types (e.g. science and public) using weighted least squares (Abdi and Valentin 2007) and graphically represents the proximity of the categories on a simple plane, i.e. correspondence map. Thus, MCA allows finding similarities between categories based on the chi-square distance between them and using the percentage of the explained variance to the new (reduced) dimensions. More details related to the method of MCA can be found in the original work Greenacre (1984). We used MCA to answer the question: Which stakeholder types often appear together in the reviewed publications?

# **2.3 Results**

We identified in total 286 scientific publications, which we further analysed according to our review protocol (see Sect. 2).

Of 286 publications, in total 81 contained all keywords of which 56 publications had their emphasis on coastal and marine fisheries. 50 publications out of 56 were categorized as case studies and were further analysed in our study (detailed description in Table 2.A1 of the Supplementary Material).

The number of publications that focused on stakeholder participation significantly increased within the last 18 years (Fig. 2.1). In 2015, a maximum value of eight was reached. The majority of the case studies was conducted in Europe (N = 18), North America (N = 11) and Australia (N = 9).

#### **2.3.1 Paper Review: Stakeholders**

#### **<IP_ADDRESS> Term Definition**

We identified four publications defining the term stakeholder (Brzezinski et al. 2010; Haapasaari et al. 2013; Tiller et al. 2015; Kinds et al. 2016) (Fig. 2.2a). Even though they defined the term more indirectly and in general, Brzezinski et al. (2010) stated stakeholders as members of a particular group that hold a personal stake. They referred to Olson (1965) to suggest that the increase of the personal stake of these members will lead to an increase of their participation in regulatory processes. Haapasaari et al. (2013) described stakeholders as a group of people having a stake and contributing towards a knowledge base for fisheries management. On the other hand, Kinds et al. (2016) focused on stakeholders as all people and organizations (here producer organizations), which are actively involved in the fishing sector. Tiller

**Fig. 2.2** Review of 50 research publications presenting case studies in coastal and marine fisheries (as of May 2018). (**a**) Term definition of participation and stakeholder; we distinguished between participation (grey) and participation-related terms (light grey), e.g. participatory

management, participatory research and participatory action research; (**b**) method application for participation (e.g. interview, workshops and questionnaire) and stakeholders (e.g. snowball sampling); (**c**) the use of stakeholder participation, either as a participation or research tool

et al. (2015) took a deliberate look into the literature, referring to Freeman (2010). Freeman (2010) defined stakeholders as any group or individual who can affect, or is affected by, the achievement of the organization's objectives (Freeman 2010). Tiller et al. (2015) continued to criticize this definition as too broad; it allows the inclusion of nearly everyone as a stakeholder.

#### **<IP_ADDRESS> Stakeholder Analysis**

Durham et al. (2014) stated that the selection of stakeholders strongly determines the outcome of the participation process. They, therefore, recommended to systematically select stakeholders based on the objective and impact of research. We, therefore, analysed the publications, looking for the description or reference of stakeholder analysis processes.

In our review corpus, 15 out of 50 publications applied methods to get an understanding of who their stakeholders are (Fig. 2.2b). We evaluated publications as using stakeholder analysis approaches if the case studies did not decide on stakeholder groups or stakeholder individuals (referring to Durham et al. 2014) but researched for them systematically. Three out of 15 publications defined stakeholder groups, three determined stakeholder groups as well as individual stakeholders and the remaining nine out of 15 case studies selected individual stakeholders out of a priori stakeholder groups.

Gray et al. (2012), Kinds et al. (2016), as well as Sampedro et al. (2017) evaluated stakeholder groups that were involved in past fisheries research and management; thereby, they have chosen the group of stakeholders they wanted to involve in their current research projects. Pristupa et al. (2016) applied three different approaches; on the one hand, they did not want to overlook a major stakeholder, and on the other hand, they aimed to identify the most knowledgeable individual within the appropriate stakeholder group: first they extracted information from reports and open-access information such as Marine Stewardship Council reports, interviews on specialized websites and scientific reports. Second, they identified stakeholders during a thematic conference, which was also used to establish contacts. Third, recommendations by fisheries experts were accumulated using the snowball approach (Pristupa et al. 2016). Different to the previous case studies, Miller et al. (2010) used two approaches to select relevant stakeholders. First, stakeholders were selected due to history, perspectives and relationships among those with a stake in a specific fishery (Miller et al. 2010). Second, relevant stakeholders should be knowledgeable and influential in their community as well as open minded for different views (Miller et al. 2010). Further, Mahon et al. (2003) analysed stakeholders based on public records before organizing discussion meetings where individual stakeholders were singled out.

Additionally, nine publications described methods that were applied to identify individual stakeholders, either within presumed stakeholder groups or randomly. Butler et al. (2015), Bitunjac et al. (2016) and Stratoudakis et al. (2015) based their choice of individual stakeholders on their long-time experience and their knowledge of the topic studied. Bitunjac et al. (2016) selected stakeholders of which the authors assumed to have a leading influence within their group and were, therefore, seen as representatives of their stakeholder group. Catedrilla et al. (2012), Kerr et al. (2006) and Murphy et al. (2015) had chosen fishers as individual stakeholders by sampling them from a registration list in their field of interest. Lorance et al. (2011) and Thiault et al. (2017) selected the stakeholders at random. Lorance et al. (2011) advertised workshops widely and, therefore, could not directly influence attendance; Thiault et al. (2017) did sampling among all households in their area of interest without focusing on a specific stakeholder group. Kittinger (2013) first conducted a snowball sampling followed by a 'purposive sampling approach' – a deliberately selective approach choosing knowledgeable individuals.

#### **<IP_ADDRESS> Stakeholder Types**

Overall the stakeholder type 'fishery' had the highest frequency of appearance within all publications, followed by 'politics', 'science' and 'eNGO' (Table 2.3). In five publications, 'fishery' was considered as the only stakeholder (Clarke et al. 2002; Catedrilla et al. 2012; Eveson et al. 2015; Tiller et al. 2015; Thiault et al. 2017). Except for Catedrilla et al. (2012), these publications aimed at getting information about the spatial distribution of fishing grounds. Two case studies (Fletcher 2005; Dowling et al. 2008) did not name 'fishery' as a stakeholder but noted that fishers were involved in the conducted case study.

'Politics', 'science' and 'eNGO' were targeted in about half of the studies. Nonetheless, 12 case studies did not consider any of these three stakeholders at all (e.g. Mitchell and Baba 2006; Appledorn et al. 2008; Cox and Kronlund 2008). The stakeholder type 'others' mostly represented a business or the like (e.g. Carr and Heyman 2012; Butler et al. 2015). 'Public' stakeholders were mainly seen as community members (Kittinger 2013; Eriksson et al. 2016) or consumers (Mahon et al. 2003), who, therefore, did not have a primary economic or political interest in fisheries.

'Related industry' was described as processing and selling industry that was directly associated with fisheries and so depended on this stakeholder type (e.g. Cox and Kronlund 2008). 'Related industry' was considered 16 times in the

**Table 2.3** Identified stakeholder types presented by case studies in coastal and marine fisheries (as of May 2018) and ranked by the frequency of their appearance (N). Description of stakeholder types corresponds to the one mentioned in the publication under review

reviewed case studies and differed widely in their topics in which context these stakeholder groups emerged, e.g. bycatch (Bojorquez-Tapia et al. 2016), stock assessment (Smith et al. 2001) or compliance (Garza-Gil et al. 2015). 'Recreational fishery' was represented in five publications, two in Australia (Fletcher 2005, Mitchell and Baba 2006) and three in North America (e.g. Miller et al. 2010; Gray et al. 2012; Murphy et al. 2015), all of them focused on management processes.

# **<IP_ADDRESS> Relationships Between Stakeholder Types**

We applied a multiple correspondence analysis to evaluate the occurrence of certain stakeholder clusters. 48 publications included 'fishery' as a stakeholder, but this stakeholder type did not group with other stakeholders and, therefore, lessened the meaningfulness of other stakeholders. For this reason, we decided to exclude 'fishery' from the MCA, which resulted in a higher percentage of the variance explained by the dimensions. As a result, very similar variable clusters of categories appeared and were, therefore, easier to interpret. 'Others' were also excluded from the MCA; by definition this stakeholder type showed a great variety, and, therefore, interpretation of the data would be difficult.

Ideally, dimensions should be used to interpret the data whose eigenvalues exceed the mean of all eigenvalues (0.17). For this reason, we included three dimensions into our analysis, which together accounted for over 70% of the variance. Here, it is important that the dimensions obtained are hierarchical. Dimension 1 formed the strongest dimension (Dim1, Fig. 2.3, Table 2.A2 of the Supplementary Material), i.e. singled out 'science', 'eNGO' and 'politics', and explained 31.6% of the variance. Further, these three stakeholder types had the highest number of mentions after 'fishery'. Dimension 2 (Dim 2, Fig. 2.A2a of the Supplementary Material) focused on 'recreational fishery' and 'related industry', accounting for 21.8% of the variance. Although 'recreational fishery' was only considered in five case studies, this stakeholder type showed a strong contribution towards dimension 2. Also, explanatory power was increased by sharing contribution with 'related industry'. Less variance (17.7%) was explained by dimension 3, which was dominated by 'public' (Dim 3, Fig. 2.A2b, Table 2.A1 of the Supplementary Material).

Subsequently, MCA was applied separately to case studies from North America (N = 10) and Europe (N = 18) (Fig. 2.A3a-c of the Supplementary Material). The results of the MCA that was performed on North America case studies showed a similar picture as in Fig. 2.3, although these case studies did not dominate the review corpus. Even though 'science', 'eNGO' and 'politics' showed a strong contribution in different dimensions, these stakeholder types could

**Fig. 2.3** Panel **a** of the visualization of correlation between dimension 1 (Dim1) and dimension 2 (Dim2), showing the variance of stakeholder types in 50 research publications of case studies in coastal and marine fisheries (as of May 2018) using multiple correspondence analysis (MCA). Figure shows which types of stakeholders are mostly corre-

lated, i.e. regarding stakeholder participation in coastal and marine fisheries, 'eNGO', 'politics' and 'science' are often addressed together. Panels b and c of the MCA results for correlation of dimension 2 (Dim2) and 3 (Dim3) as well as dimension 1 (Dim1) and 3 (Dim3) are presented in Fig. A2 of the Supplementary Material

still be found as a group. In dimension 2 'related industry' and 'recreational fishery' were displayed in the negative area; the other stakeholder types moved from the negative area of dimension 2 into the positive area. 'Related industry' and 'recreational fishery' were also grouped together with a high contribution as seen in Fig. 2.A3a (Supplementary Material); 'public' was found apart.

We showed clearly that in European case studies, 'related industry' and 'public' as well as 'science' and 'eNGO' grouped together. 'Politics' was rather set apart and did not contribute much to dimension 1. 'Politics' solely dominated dimension 3; 'recreational fishery' did not appear in the case studies conducted in Europe.

#### **2.3.2 Paper Review: Participation**

#### **<IP_ADDRESS> Term Definition**

In total, four publications defined the term participation (Brzezinski et al. 2010; Tiller et al. 2015; Pristupa et al. 2016; Sampedro et al. 2017); three publications described participation-related terms (Kittinger 2013; Hara et al. 2014; Trimble and Lazaro 2014) (Fig. 2.2a). After Sampedro et al. (2017), participation could take many different forms, e.g. from planning (Neis et al. 1999; Johannes and Neis 2007; Johnson and van Densen 2007) to co-management experiences (Berkes 2003; Wilson et al. 2003). Participation was described as a role that benefits the participating stakeholders (Brzezinski et al. 2010) and a strategy of involving the stakeholders in decision-making processes (Tiller et al. 2015). Further, dependent on the strategy of involvement, stakeholders could get further responsibilities in the results of the conducted participatory process (Tiller et al. 2015). Moreover, participation referred to the type and level of stakeholder or beneficiary involvement (Hickey and Kothari 2009; Pristupa et al. 2016). Pristupa et al. (2016) explained that countries had developed a whole range of formal mechanisms stipulating citizens and stakeholder participation, e.g. consultations, referendums and elections; the participation of the private sector was still challenging.

Within three case-study publications, participatoryrelated terms had been described, e.g. participatory management (PM, Hara et al. 2014), participatory research (Trimble and Lazaro 2014) and participatory action research (PAR, Kittinger 2013). PM or co-management was defined as an institutional and organizational arrangement for effective management between government and user groups (Hara et al. 2014). The function of PM was described as the sharing of power and the responsibility for the management decisionmaking, the encouragement of partnerships and provision of user incentives for sustainable use of resources (Wilson et al. 2003; Hara et al. 2014). Participatory research was defined as one way to create power sharing between researchers and communities for, e.g. developing resource management strategies (Arnold and Fernandez-Gimenez 2007; Trimble and Lazaro 2014). Related to the degree of participation or the relationships between researchers and the community, different modes of participatory research occurred (Trimble **Fig. 2.4** Frequency of the appearance of active (workshop, interview, meeting, discussion, questionnaire, survey, modelling, conversation, mapping) and passive participation tools (coordination, presentation), related to stakeholder participation described in coastal and marine fisheries research publications (as of May 2018)

and Lazaro 2014), e.g. contractual, consultative, collaborative and collegiate (Biggs 1989), co-option, compliance, consultation, cooperation and co-learning (Kindon 2008). Kittinger (2013) used the term PAR, which is defined as a set of approaches related to the involvement of researchers and community members working collaboratively in the visioning, goal-getting, data gathering as well as assessment phases of research (Whyte et al. 1989; Kittinger 2013).

#### **<IP_ADDRESS> Participatory Tools**

In contrast to the definition of participation, 45 publications focused on the description of participatory tools (Fig. 2.2b). We identified 11 participatory tools, which were divided into nine active and two passive participatory tools (Fig. 2.4). Active participation tools included workshops (N = 20), interviews (N = 19), meetings (N = 15), discussions (N = 15), questionnaires (N = 9), surveys (N = 9), modelling (N = 19), conversation (N = 3) and mapping (N = 2). Coordination (N = 5) and presentations (N = 3) represented passive participation tools (Fig. 2.4).

We detected no changes in the number of publications over time using passive methods. In contrast, we found a significant increase in the number of case studies applying active methods with a peak in 2015 (N = 19) (Fig. 2.5).

Table 2.4 presents utilized tools and related sub-tools. Here, the highest number of sub-tools was presented by interviews, including sub-tools (N = 14), e.g. semi-structured interview (e.g. Carr and Heyman 2012; Stöhr et al. 2014; Yates and Schoeman 2015; Rivera et al. 2017), unstructured interview (Hara et al. 2014) and key informant interview **Table 2.4** List of active as well as passive participation tools and including sub-tools, described within 50 research publications presenting case studies in coastal and marine fisheries (as of May 2018) between 2000 and 2018

(Eriksson et al. 2016). Meetings and workshops showed the second and third highest number of sub-tools. Here, meetings were presented, with sub-tools (N = 10), e.g. roundtable meeting (Kerr et al. 2006), joint planning meeting (Kittinger 2013) and face-to-face meeting (Miller et al. 2010). However, workshops were shown, including sub-tools (N = 7), e.g. stakeholder workshop (Eriksson et al. 2016; Burdon et al. 2018) and participatory workshop (Bojorquez-Tapia et al. 2016). Passive participation methods included coordination, with sub-tools (N = 3), e.g. voting (Miller et al. 2010; Thiault et al. 2017; Zengin et al. 2018), rating (Goetz et al. 2015), evaluation (Cox and Kronlund 2008) and presentation, including sub-tools (N = 4), e.g. video (Clarke et al. 2002), poster (Kerr et al. 2006), exhibition (Kerr et al. 2006) and tableaux (Kerr et al. 2006). We also determined whether preparatory work was performed and described within the case studies under review. Among others, observations (Delaney et al. 2007; Granados-Dieseldorf et al. 2013; Trimble and Berkes 2013; Stöhr et al. 2014; Trimble and Lazaro 2014; Mabon and Kawabe 2015), fieldwork (Mabon and Kawabe 2015; Sampedro et al. 2017) and visits (Kerr et al. 2006) were carried out. Furthermore, newsletters (Kerr et al. 2006) and e-mails (Lorance et al. 2011) were sent out to call for participation within different stakeholder types. Moreover, telephone calls (Kerr et al. 2006) were made, and consultations took place, e.g. consultation with stakeholders (Cox and Kronlund 2008; Mapstone et al. 2008; Williams et al. 2011).

#### **<IP_ADDRESS> Intention for Participation**

Within this review, we looked at the diversity of the intention for participation; we classified these intentions as types and sub-types (Table 2.5).

The intention types identification (N = 20), with subtypes, e.g. target species (Fletcher 2005), ways of communication (Zengin et al. 2018), stakeholder characteristics (Bojorquez-Tapia et al. 2016; Kinds et al. 2016; Burdon et al. 2018) and assessment (N = 12), with sub-types, e.g. management system (Lorance et al. 2011), knowledge (Carr and Heyman 2012) and data (Catedrilla et al. 2012) occurred most often (Fig. 2.6). Establishment (N = 5), development (N = 7), evaluation (N = 7) and improvement (N = 7) occurred moderately often (Fig. 2.6). Less widely used were analysis (N = 3), definition (N = 2), description (N = 2) and feedback (N = 2) (Fig. 2.6).

Establishment (N = 10), assessment (N = 7) and identification (N = 7) had the most sub-types within the case studies under review*.* Improvement (N = 5), development (N = 4) and evaluation (N = 4) showed a moderate diversity of subtypes, whereas feedback (N = 2), e.g. feedback from stakeholders on the meeting (Dowling et al. 2008), as well as description (N = 2), e.g. knowledge about socio-ecological systems (Gray et al. 2012) and management implications (Smith et al. 2001) presented the lowest diversity of sub-types.

# **2.3.3 Reflection on the Joint Term Stakeholder and Participation**

In the final evaluation, we analysed the application of stakeholder participation as one term. We first evaluated whether

**Table 2.5** Types and associated sub-types of intentions for participation determined within 50 research publications focusing on stakeholder participation in coastal and marine fisheries from 2000 to 2018

(continued)

**Table 2.5** (continued)

stakeholder participation was used for doing research on stakeholders or if the case studies were conducted with the participation of stakeholders. Overall, 24 publications utilized the term stakeholder participation for the research on stakeholders (research tool); 21 publications used stakeholder participation in their conducted case study (participation tool). Within five case studies, it was uncertain whether stakeholder participation was used or not (Fig. 2.2c).

In the case study conducted by Kinds et al. (2016), the term stakeholder participation was used to describe the development of a sustainability tool with the direct input from users, i.e. fishers. Here, the wishes and preferences of stakeholders were recognized and implemented to improve the output of the utilized tool but not to influence decisionmaking processes (*research tool*). Rivera et al. (2017) carried out semi-structured interviews to assess stakeholders' perceptions to identify management, biology and socioeconomic drivers related to the gooseneck barnacle fishery in Spain. This case study used the term stakeholder participation, but no influence on the management by stakeholders was mentioned (*research tool*). Tiller et al. (2015) applied an integrated approach of two methods, Systems Thinking and Bayesian Belief Networks, to elicit stakeholders' opinions through participatory engagement. Both methods were used to investigate, e.g. how stakeholders perceive the ecological system in the Trondheimsfjord, but with no further impact on decision-making processes (*research tool*). Through the method of Systems Thinking, shared mental models of the ecological system in the Trondheimsfjord were developed. Bayesian Belief Networks were further used for exploration of the priority issues as well as to represent causal relationships between defined variables. In contrast, Trimble and Berkes (2013) presented the concept of participatory research, i.e. involving fishers and policymakers as well as managers among other stakeholders in the case of a sea lion population and a fishery in Uruguay. Within this case study, stakeholders, e.g. fishers had an impact on decision-making processes related to the management of the sea lion population (*participation tool*). Williams et al. (2011) conducted a case study based on the participation of commercial fishers, defining various alternative management strategies related to the Torres Strait Finfish Fishery (TSFF) in Australia, i.e. sea-

sonal closure, large minimum capture size, to provide a framework for impartial evaluation of management strategy performance (*participation tool*). In addition, Stöhr et al. (2014) described the concept of stakeholder participation by evaluating two case studies; only the Polish case had a coastal and marine focus. Within this case study, roundtables were applied to create a multi-stakeholder platform with the objective of informing and influencing decision-making processes (*participation tool*).

# **2.4 Discussion**

In total, 50 case studies focusing on stakeholder participation in coastal and marine fisheries were identified and reviewed. Most of the publications did not define the term stakeholder or participation or described a systematical approach of selecting stakeholders. Moreover, stakeholder participation was mentioned in all 50 publications, but only half of the case studies involved stakeholders in the process of participation.

It should be noted that we could only show what has been described in the publications under review; here, we did not present a comprehensive overview of all relevant stakeholder types that would be possible in the respective contexts.

#### **2.4.1 Stakeholder**

#### **<IP_ADDRESS> Term Definition and Stakeholder Analysis**

Four case studies defined the term stakeholder and, thus, showed a scientific examination of potentially concerned stakeholder types; 15 publications used a systematic description of how stakeholders were identified. The other publications used intuitive decisions to identify relevant stakeholders in their case study. This led to the fact that, related to our research focus on coastal and marine fisheries, the stakeholder type 'fishery' was mostly involved; 'public' stakeholders were only rarely involved.

All case studies included 'fishery' as a stakeholder type. Therefore, we proposed that 'fishery' is seen as the main stakeholder type in coastal and marine fisheries research. Mahon et al. (2003) supported this thesis literally by writing that within the conducted case study, the primary stakeholders are the fishers. In some publications, 'fishery' was even the only stakeholder type considered. Although at first sight this realization might seem logical, it can be discussed; fisheries are harvesting a common resource and, therefore, do not necessarily contribute towards the sustainable exploitation of coastal and marine fisheries resources, as most case studies consider stakeholder participation as a way of implementing more sustainable fisheries management (e.g. Wilson et al. 2003; Thiault et al. 2017). Although not all forms of fisheries were considered unsustainable, artisanal fisheries, for example, were often associated with having a small impact on fish stocks (Carvalho et al. 2011) but have been proven to cause impact beyond sustainable levels (Pomeroy 2012); they also deal with other sustainability issues such as bycatch of birds (Almeida et al. 2017).

Within our review, we used the category 'others' to classify stakeholders that did not fit into any other category. This fact shows very clearly that, on the one hand, there is great diversity of stakeholder types within the field of coastal and marine fisheries research; on the other hand, it describes existing discrepancies in the understanding of the term definition and the classification of corresponding stakeholders. We, therefore, suggest to clearly define the term stakeholder as well as to discuss their role in the specific context of the conducted case study. Although Tiller et al. (2015) criticized the stakeholder definition by Freeman (2010) as too broad, they did not give a clear term definition either in their own case study. We assume that there is a high risk of excluding relevant stakeholder types, when not applying a term definition for stakeholder as well as not using a stakeholder analysis tool to ensure that relevant stakeholders are approached. This could lead to the fact that, for example, no local ecological knowledge or fisheries ecological knowledge would be recorded for the corresponding case study, which is important inter alia for better understanding the marine ecology and making results more convincing for resource users (Davis et al. 2004) and, therefore, increase the legitimacy of resource management (Aanesen et al. 2014). It is not important to include all stakeholders available but to choose them carefully according to the objectives of the case study, which means applying a stakeholder analysis approach (Durham et al. 2014).

#### **<IP_ADDRESS> Stakeholder Clusters**

We showed, with using MCA, that 'eNGO', 'politics' and 'science' are often addressed together within the strongest dimension. Therefore, we could conclude that these stakeholder types were considered important within many conducted case studies. This dimension described stakeholders that deal with a rather theoretical side in the field of fishery, i.e. in the form of regulations, research or campaigns. It can be argued that these stakeholders contributed towards research and management as well as towards different forms of sustainability; therefore, 'eNGO', 'politics' and 'science' have a more sustainability-oriented attitude. This finding is strongly supported by Aanesen et al. (2014); they concluded that, under the European Common Fisheries Policy, authorities, scientists and NGOs have a similar perspective on fisheries management. This is rather obvious for 'eNGO', as they are seen as representing the ecological sustainability. By contrast, 'politics' could be interpreted as representing the population, i.e. this stakeholder group acts in the interest of the sustainability of food, but is also driven by the economic sustainability. 'Science' could be seen as the representative and provider of research. We suggest that these stakeholder groups have a general interest in sustainable management and are not directly or financially dependent on the resource fish. Of course, it can be argued that certain jobs of eNGOs, scientists or politicians depend on the debate as well as on the public interest in fish and fishery. But this argument is to be classified as marginal in this context. One reason is that fish is one of the main protein sources for humans; even if the resource fish would shrink, it will always be of interest for certain stakeholder types.

In our sample of publications, 'politics', 'eNGO' and 'science' were mentioned most frequently after 'fishery'. For that reason, we can assume that these three stakeholder groups are deemed the second most important stakeholder groups. It can be discussed that 'politics', 'eNGO' and 'science' should have at least an equally strong stake in fisheries research compared to 'fishery'.

Another group displayed by MCA is formed by 'related industry' and 'recreational fishery'. Both stakeholder groups mostly occurred in the second strongest dimension, which can be interpreted as stakeholders who are handling the resource fish and, therefore, dealing with it in a practical way. Although they also have an interest in sustainable management, they, unlike 'science', 'politics' and 'eNGO', depend financially (especially 'fishery') or mentally (e.g. 'fishery' and 'recreational fishery') on the resource fish. Therefore, profit or benefit orientation can be seen as another factor describing dimension 2. This is supported by the fact that the two groups (dimension 1: sustainability vs. dimension 2: dependence) discussed are placed far away from each other in the MCA. Both stakeholder groups cannot be seen as independent from each other as their decisions are influencing each other's actions, e.g. if political regulations or campaigns led by 'eNGOs' resulted in decreasing harvest rates of fish, commercial and recreational fishers are negatively affected. We take a critical look at these stakeholder groups, as they are presented apart from each other in the conducted MCA and, therefore, are not engaged equally in the reviewed case studies. We recommend to engage these stakeholder types more equally. The cooperation between fishery-related stakeholders and scientists could lead to more informed stakeholders on both sides; therefore, a greater mutual understanding, trust as well as likelihood of long-lasting partnerships could be achieved (Hartley and Robertson 2006).

We showed that 'public' participation is relatively low in the field of coastal and marine fisheries research. This fact is reflected among other things in the low numbers of mention within the case studies. Here, 'public' as one stakeholder group contributed the least to the two strongest dimensions. On the one hand, the low involvement could be interpreted as a lack of interest. On the other hand, we argue that public stakeholders were not directly addressed within the publications. In relation to the definition we used to classify 'public', it can be critically discussed that 'eNGOs' could also be seen as representatives of the civil society (e.g. Pristupa et al. 2016) and community leaders could include voted politicians (Rivera et al. 2017). But we decided to stick to the stakeholders as they were mentioned in the publications. The results showed that 'public' stakeholders are not part of any group; nevertheless, they dominated the weakest dimension and explained the high percentage of its variance.

Data from North American and European case studies resulted in different MCAs. This can be seen for example with 'recreational fishery'. Although this stakeholder type is part of the European Common Fisheries Policy, they are not considered as stakeholders in any of the case studies conducted in Europe. This is different for North American case studies; here 'recreational fishery' was seen as a stakeholder type. Even if this analysis gave only a small insight into the topic, regional differences related to stakeholder types could already be made clear here. These differences cannot be explained by different management systems, because both in Europe and in North America recreational fisheries are included in their regulations; the results further need to be investigated. Furthermore, we assumed different emphases of stakeholder types; therefore, when applying MCA to different regions, different interpretations of the dimensions have to be made. However, the small sample size for regional MCAs could reduce the significance of such interpretations.