Brown Trout are commonly 12 to 20 inches long and weigh a couple pounds. The Montana state record Brown Trout weighed 29 pounds and last year a new world record Brown Trout was caught in Michigan and tipped the scales at over 41 pounds. They can live to an age of 20 years.
Coming to North America
The ones that live in lakes usually move into streams to spawn in the fall. Brown Trout are considered to be native to Europe and western Asia and were widely introduced to North America in 1883 and in 1889 to the Madison River, a prime trout stream flowing west out of Yellowstone National Park and then north to help form the Missouri River.
The results of plant, fish or animal introductions are not always seen favorably. It is usually long after the fact that we become aware of the consequences. Today, keeping native ecosystems whole and free of invasive species is seen as the best way to keep those communities healthy.
Awareness of the potential problems led to efforts to overcome them. Submerged rocks, undercut banks and overhanging vegetation provide protection from predators, sunlight and warmer temperatures.
In The Bighorn
However in the height of the drought in 2003, brown trout set record lows of only 492 per mile and not enough rainbows were recaptured to make valid population estimates. Higher water years have helped populations start a comeback, but more good water years are needed to return the Bighorn River to a world class fishery.
Did You Know?
Prior to the completion of Yellowtail Dam, the Bighorn River was a muddy, warm water prairie stream. The dam transformed the river into a cold, clear tailwater ideally suited to rainbow and brown trout, and aquatic insects. The Bighorn River now draws visitors and anglers from around the globe. More...