[2] When the lighthouse was staffed the keepers kept livestock, including cattle, sheep and draught horses, and maintained grassland for their grazing.

[3][4] Tasman Island is a very important breeding site for fairy prions, with an estimated 300,000-700,000 pairs, making it the largest such colony in Tasmania, and possibly in Australia.

It has been identified as an Important Bird Area (IBA) by BirdLife International because it supports over 1% of the world population of the species.

[1][3] The breeding seabirds were preyed on by a feral cat population estimated at 50, feeding mainly on fairy prions and taking about 50,000 birds annually.

[6][3][7] Australian and New Zealand fur seals use the rocky shore as a haul-out site, and the latter species has bred there in small numbers.