The island is a haul-out site for the Australian Fur Seal.

Illiswilgig is a main pupping and haul-out site for grey seal.

Cormorant also breed on the island and it is a main pupping and haul-out site for grey seal.

The island is used occasionally as a haul-out site by Australian Fur Seals.

Up to 1200 Australian Fur Seals use the rocks as a regular haul-out site.

Australian Fur Seals use the island as a haul-out site.

The rocks are also used as a haul-out site by Australian Fur Seals.

It is also used as a haul-out site for Australian Fur Seals.

The outer sandflats are also a haul-out site for both common and grey seals.

Numerous reserves and protected areas at rookeries and haul-out sites exists for the sea lions.