Introduction

There's trouble in the waters of the U.S. Northern Rockies and Northwest states. Long known as the home of America's finest blue-ribbon fishing streams, its native trout are declining at an alarming pace. A coherent plan of action is urgently needed to prevent the disappearance of native stocks of bull trout. The Bull Trout (Salvelinus confluentus) is the Northwest?s largest native migratory trout. An average adult weighs five pounds. The U.S. record came from Idaho?s Lake Pend Oreille, weighing in at a whopping 33 pounds! Bull trout are also known for their tremendous spawning journeys of up to 175 miles. Historical accounts tell of thousands of spawning trout in virtually every mountain stream, and bull trout also played a significant role in Native American culture. Despite this rich legacy, our native trout are now gone from most of their range and the last strongholds are now threatened.

Indicator Species
Bull trout depend on very clean, cold water and therefore are a prime indicator of the health of forest ecosystems and watersheds. Extremely sensitive to human-caused changes to their environment, bull trout are a monitor of our own quality of life. Bull trout are less tolerant of disturbances to their habitat than are other salmonids. Protection of bull trout will accordingly also protect the habitat of numerous other species, while maintaining high water quality.

Life History
The bull trout is a char that is taxonomically separate species from its coastal relative Dolly Varden (Salvelinus malma), although they share similar life histories. Four distinct patterns have been identified: resident, fluvial, adfluvial, and anadromous- the latter reported only near Puget Sound in Washington where anadromous bull trout grow large in the salt water and then migrate to mountain tributaries to spawn. More common is the inland migratory strategy. Adfluvial bull trout grow to adulthood in lakes and migrate to streams for spawning. Fluvial bull trout follow the same pattern only they grow large in rivers. Resident bull trout, isolated by blockages to migration and damaged habitat, spend their entire life in the same body of water. Spawning maturity occurs at four to six years. Unlike salmon, spawning adults survive to spawn again every two or three years.

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