Fish can be found in many of the lakes and streams of Cape Breton Highlands National Park as well as along the coast outside the park.

Freshwater fish

There are ten species of freshwater fish native to Cape Breton Highlands National Park—less than one third of the species found on mainland Nova Scotia. The small variety of freshwater species is due mainly to natural barriers such as the ocean and the mountains, as well as low water levels in summer. The oxygen-rich waters are ideal for trout and salmon.

The eastern brook trout lives in most of the park's lakes and streams, and the Atlantic salmon spawns in most of the larger rivers, with an unusual early spring run in Chéticamp River. Brackish ponds near the coast support smelt, gaspereau, sticklebacks and banded killifish.

From the 1950s until the mid 1970s, some of the lakes and rivers in the park were commonly stocked with trout and salmon. Two lakes were even poisoned to get rid of fish species such as American eel, smelt, gaspereau and white perch which were not deemed desirable for sport fishing. Nowadays the park is working to keep the lakes, rivers and fish populations as natural as possible and stocking no longer occurs.

Rainbow trout and brown trout, two non-native fish species, occur in small numbers.

Saltwater fish

A variety of saltwater fish occur off and near the coast including Atlantic cod, haddock, halibut, herring and mackerel. Several species including Atlantic cod, Atlantic salmon and haddock can no longer be fished commercially because of their small population size.

Cartilaginous fish such as sharks, skates and stingrays also live in the saltwater around the park. The sharks that are most commonly sighted near Nova Scotia are the spiny dogfish and the blue shark. The large but harmless plankton-eating basking shark, an IUCN Redlist vulnerable species, is often seen near Nova Scotia as well.

Checklist of freshwater fish in Cape Breton Highlands National Park
Family (Common Name)
Species Scientific name Status within park
Salmonidae (Salmon and allies)
Atlantic salmon Salmo salar Common to uncommon
Brook trout Salvelinus fontinalis Abundant
Brown trout Salmo trutta Uncommon - introduced to NS
Rainbow trout Salmo gairdneri Rare - was stocked
Osmeridae (Smelts)
Rainbow smelt Osmerus mordax Rare
Anguillidae (Freshwater eels)
American eel Anguilla rostrata Common
Clupeidae (Herrings)
Gaspereau (alewife) Alosa pseudoharengus Locally Common
Cyprinodontidae (Killifishes)
Banded killifish Fundulus diaphanus Uncommon
Gasterosteidae (Sticklebacks)
Threespine stickleback Gasterosteus aculeatus Rare
Fourspine stickleback Apeltes quadracus Rare
Ninespine stickleback Pungitius pungitius Rare
Percithyidae (Temperate basses)
White perch Morone americana Rare