The island supports a good population of
reptiles - four
skinks and one
gecko. One of the species of skink,
Ctenotus labillardieri, has evolved into a distinctive insular race on the island. There are no
snakes on the island. Marine
mammals such as
New Zealand fur seals and
Australian sea lions inhabit Bald Island. There are a few mainland mammals including the
quokka, and a population of
Gilbert's potoroo is also being established. The island forms part of the
Two Peoples Bay and Mount Manypeaks Important Bird Area, identified as such by
BirdLife International because of its significance in the conservation of several rare and threatened bird species. It acts as an important
breeding ground for
great-winged petrels and
little penguins.
Translocations of endangered species Due to its remote location, and lack of
predators, the island was chosen in August 2005 as a site for the translocation of a
Gilbert's potoroo population, with a total of 10 animals moved there, between making a total of 14. At that time just 40 individuals remained in the wild, in
Two Peoples Bay Nature Reserve. Another endangered species translocated to Bald Island is the
noisy scrub-bird. In 1992 five males were taken from the Two Peoples Bay area and taken to Bald Island. In 1993 the area was surveyed to show that at least two had survived. In 1993 another three males and three females have been relocated to Bald Island. The estimated population of calling male birds on Bald Island in 2004 is 59 individuals.{{cite web|url=http://www.birdlife.org/datazone/ebas/index.html?action=SpcHTMDetails.asp&sid=5164&m=0|title=Birdlife International - Noisy Scrub-bird - BirdLife Species Factsheet ==References==