ilha das baleias, 'whales' island', is located in the northeastern edge of the sepetiba bay, an area of incredibly rich wildlife, where the fresh streams from the 'maciço da pedra branca' intertwine with the salt waters of the bay and the atlantic ocean beyond.

while the name may suggest the presence of whales around this island, the position of it makes it unlikely that any whales sighting could occur.

however, the region is home to several cetaceans species that can often be observed, especially in the summer, such as the Balaenoptera edeni, the Balaenoptera acutorostrata, the Stenella, the Megaptera novaeangliae, the Orcinus orca and the Sotalia guianensis.