The International Union for Conservation of Nature (IUCN) World Heritage Outlook cited the Everglades National Park 2020 Conservation Outlook as "Critical." Assessment of current trends were concluded to be "deteriorating" with "very high threat" to the overall health of the ecosystem. Unfortunately, some ecological features now lost cannot be restored as they were initially developed over decades to centuries.[145] The surviving ecological features are of vital importance to protect due to their essential support of the state of Florida and their unique properties, unknown elsewhere in the world and are of invaluable consequence to multiple fields of study.