The government of Newfoundland and Labrador estimates that the site is home to 30,000 northern gannets,[2] 20,000 black-legged kittiwakes, 20,000 common murres, and 2,000 thick-billed murres, as well as dozens or hundreds of razorbill, and black guillemot breeding pairs.

[4] In addition to the numerous birds, humpback whales may be viewed from the heights during the annual capelin run.

The area protected by the reserve also includes sub-Arctic tundra, a mainly treeless plateau bordering the ocean.

A footpath from the centre leads to a viewing location a few hundred metres from "Bird Rock", a large sea stack with several thousand nesting gannets.

Inside the interpretive centre, visitors will also find The Rookery Nature Store, operated by the Friends of Cape St. Mary's.