Hidden in a very limited number of Adirondack lakes is a jewel of a fish, the Frost Fish. The Frost Fish or Round Whitefish is an endangered species that is only known to exist naturally in approximately seven lakes within the Blue Line. This indicator of clean water is actually a relative of salmon, trout and char. Being of the family Salmonidae, they live in cold, deep lakes with adequate dissolved oxygen.

What makes the Round Whitefish so unique, is that they will spawn in late November, early December over gravel. They have even been known to spawn under the ice. The eggs will drift down into the cracks between the rocks to wait for the warmth of spring to hatch. Unfortunately it seems, that the deck is stacked against this important forage species.

The Round Whitefish is a cigar shaped fish with a small mouth and an adipose fin. They range in color from olive green/ gray to a silvery yellow. They feed primarily on benthic macro invertebrates found on the substrate, such as small mollusks and mayfly larvae. They were historically hard to catch, but greatly prized.

Historically the Round Whitefish were known to be present in almost 90 lakes in the park. Seventy-five million fish were stocked into Adirondack waters from 1895 till 1918, many of these efforts to introduce the species to new waters failed. Today natural populations can be found in Little Moose Lake, Moose Pond, Newcomb Lake, Lower Cascade Lake, Upper Ausable Lake and Upper Cascade Lake. Another 8 bodies of water have populations due to successful stocking attempts. Today there are many threats to the Round Whitefish population.

The decline in the Round Whitefish can be attributed mostly to the introduction of non-native species. Species such as Smallmouth Bass, Yellow Perch and Rainbow Smelt have been stocked to enhance the fishing within the Adirondacks. These species will then feed on the eggs and young of the Round Whitefish and other native species. Other factors contributing to the decline in Round Whitefish populations are climate change, eutrophication, algal growth, acid deposition, and possible overfishing.

Important species of fish, such as Lake Trout forage or eat Round Whitefish. When their populations decline, the Lake Trout switch to feeding on other species such as Rainbow Smelt. Smelt, while abundant and yummy are not a healthy food source. Lake Trout that feed primarily on smelt have been known to have poor spawning success due to illness and deficiencies.

While efforts are ongoing to bring this important species back from the brink, stocking alone will not succeed. We must remember not to introduce new species to bodies of water that they have not historically been found in. Even the accidental introduction of baitfish can be harmful. Help save the Adirondack waters for native species, such as the Round Whitefish.

Photos; Above: Newcomb Lake, Middle: Round Whitefish Sign, Bottom: Lower Cascade Lake, Courtesy Blueline Photography, Jeremy Parnapy.

Corrina Parnapy is a Lake George native and a naturalist who writes regularly about the environment and Adirondack natural history for the Adirondack Almanack.