It contains the country's southernmost point, at 10°51'53"N,15°43'36"W. It is part of the João Vieira and Poilão Marine National Park.

7000 and 29,000 green sea turtle (Chelonia mydas) nests are laid per year at the globally important site of Poilão Island.

[7] The island is part of the João Vieira and Poilão Marine National Park, which was established in 2000.

Upon request, these communities are allowed to use land or hunt turtles for traditional ceremonies.

[6] During negotiations to create the park, it was agreed that the number of turtles used in traditional ceremonies would be reduced and that access to the sacred islands would be granted to a small number of researchers and tourists (although research is limited to the beach, with the forest remaining off-limits).

[3] The islands sacred status has contributed to it becoming a very successful green sea turtle nesting site.

Beginning in 2019, eggs from overlapping nests began to be moved to João Vieira.

[11] Monitor lizards on the island occasionally predate turtle nests, as do Ocypode cursor crabs.