Seabird in the Cretaceous, with a species called "Tytthostonyx glauconiticus", which seems allied to the Procellariiformes and Pelecaniformes. In the Paleogene both pterosaurs and marine reptiles became extinct, allowing seabirds to expand ecologically. These post-extinction seas were dominated by early Procellariidae, giant penguins and two extinct families, the Pelagornithidae and the Plotopteridae (a group of large seabirds that looked like the penguins). Modern genera began their wide radiation in the Miocene, although the genus "Puffinus" (which includes today's Manx shearwater and sooty shearwater) might date back to the Oligocene. The highest diversity of seabirds apparently existed during the Late Miocene and
Cape Byron Marine Park identifies the migratory little tern "(Sterna albifrons)" and the Beach stone-curlew "(Esacus neglectus)" as endangered. Seabirds that utilize the Cape Byron Marine Park are the providence pretal "(Pterodroma solandri)", flesh-footed shearwater "(Puffinus carneipes)", and the masked booby "(Sula dactylatra)" which are protected under the National Parks and Wildlife Act 1974. Although no invertebrates have been identified as endangered or vulnerable, it is important to acknowledge that there are a plethora of invertebrates within the Cape Byron Marine Park which are critical to the health of the local ecosystems. These include a variety of molluscs such as the gold ring cowries