Audubon's shearwater underparts are white, as is the head below eye level. The iris is dark, the feet are dull pink with a black wash and black toenails, and the bill is grey, darker towards the tip, and with a pinkish hue. Males and females look alike. Immature birds do not have a distinct plumage, while the nestlings are covered with down feathers, grey above and whitish on the belly. It can be confused with the Manx shearwater ("P. puffinus"), which has white undertail coverts and in direct comparison a longer bill. Other similar-looking species are usually completely allopatric, though the largely
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