Most of the vegetation that covers the island consists of lichen, moss, sedges, and dwarf black spruce.

Freshwater streams that flow into southwestern James Bay carry sediments and abundant nutrients that help to sustain the productive waterfowl habitat around Akimiski Island.

[3] The coastal waters and wetlands of Akimiski Island (and James Bay in general) are important feeding grounds for many varieties of migratory birds.

In the springtime, the birds tend to reside in the southern areas of James Bay until the northern section thaws.

Among mammals, ringed seals, polar bears, and beluga whales can be found in the area.