Ivvavik does, however, provide a refuge that with careful management, will be able to sustain healthy populations of wildlife for many years to come. Fish Arctic grayling and Dolly Varden char are the best known fish species in the park. The most distinctive feature of grayling is their large dorsal fin that ripples like an unfurled sail. Grayling feed extensively on insects, of which there are an abundance in the northern Yukon. The Firth and Babbage rivers host healthy populations of char.
Underground springs occur on several of the rivers and creeks in the park.
At some of these springs fresh water continues to percolate to the surface year-round. As a result of this continual flow, these waterbodies do not freeze to the bottom. It is here, in the fish holes, that char and grayling can overwinter. Associated with the spring is 'aufeis'. At the river surface the percolating water freezes forming ever thickening layers of ice.