Brook Trout Status and Distribution

This summary report presents information on the status of brook trout populations in 17 states in the Appalachian region, an area that represents 70% of the historical range of brook trout in the United States.  This report also identifies the principal threats identified by regional experts to the continued viability of brook trout populations on a state-by-state basis.

In total, the assessment team evaluated 11,400 subwatersheds to determine the strength of brook trout populations.  While subwatersheds vary in size, they typically contain 25 to 75 miles of streams.  Approximately half (5,563) of those subwatersheds historically supported brook trout.  The following table presents the current status of brook trout populations in those subwatersheds where brook trout historically thrived.  (View Maps [1])

The assessment data tells a somber story of brook trout decline across their range, but the data also offers hope for restoration and recovery in many areas.  Strong, healthy subwatersheds do exist, but they are rare.  The majority of these intact subwatersheds are located in Maine, New Hampshire, New York, Vermont and Virginia.  Pennsylvania, Maryland, West Virginia and the other New England states each possess only a handful of these intact subwatersheds.  Brook trout are extirpated from over 20% of the subwatersheds across the Eastern range and have vanished from all streams and rivers within those areas.

Based on scientific, on-the-ground information gathered within the last ten years, the following table shows the states with the greatest percentage of intact and extirpated subwatersheds.

* New York figure was calculated by multiplying the number of watersheds (5th level hydrologic unit) x 2.5, since subwatershed (6th level hydrologic unit) data is not yet available for the state.  On average, there are 2.5 subwatersheds within any given watershed in New York.