Brook trout

The brook trout is native to eastern Canada as far west as the western side of Hudson Bay. Within the US, it is found within the Great Lakes region, New England, and the Mid-Atlantic states extending southward along the Appalachian Mountains to northern Georgia. It has been introduced widely elsewhere within North America and temperate regions of other continents.

Within New Jersey, brook trout are confined to small cold headwater streams. They have been extirpated from many watersheds in which they once occurred and can now only be found within the northwestern portion of the state as well as one watershed in southern New Jersey.

This species inhabits clear, cool, well-oxygenated creeks, streams, small to medium rivers, and lakes. Some populations are anadromous, They prefer water temperatures between 14-16 C and do poorly when water temperature exceeds 20 C for extended periods of time.

Though they do prey on other fish, brook trout primarily feed on terrestrial and aquatic insects and crustaceans, usually during the early morning and evening.

Adults in streams may defend small feeding territories. Spawning occurs in late summer or fall in water usually less than 15 C in temperature and usually over gravel beds in shallow headwaters. Eggs are buried in nests within gravel and will hatch anywhere between 47-165 days depending on temperature (higher temperatures = fewer days). They are sexually mature in 2-3 years and may live for as long as 10 years in some portions of their range.

The brook trout is the state fish of New Jersey and is the only trout species native to the state. It is popular amongst recreational fishermen and the state’s Division of Fish and Wildlife raises and releases this and several other trout species every year.

This species is sensitive to warming water. Increased stream temperatures caused by climate change have negatively impacted this species and may continue to do so. Additional threats to this species include habitat loss, barriers (dams and roads), pollution, and competition with non-native trout species (brown trout and rainbow trout). Its population has declined in New Jersey and it has disappeared from portions of its range in the state. It likely survives today in less than half of its original (pre-colonial) range within the state with fewer than ten disjunct populations left in New Jersey.

In 2016, the New Jersey Endangered and Nongame Advisory Committee recommended a Special Concern status for this species, but no formal rule proposal has been filed to date.