Bull trout spawning strong in North Fork

By JIM MANN/Daily Inter Lake

An annual survey of bull trout spawning activity has found higher redd counts in the North Fork Flathead Basin, and counts below average in the South Fork Flathead and Swan River drainages.

Montana Fish, Wildlife and Parks field crews completed the counts of redds - distinctive spawning beds - between Sept. 24 and Oct. 22. The surveys focus on stream index sections that have been monitored every year for nearly three decades.

It was the 29th year for monitoring the Flathead Lake bull trout population by counting redds in spawning streams in the North and Middle forks of the Flathead River.

This year's count of 225 redds in eight index sections was well above the recent average and the third-highest count in the last 17 years.

The counts dropped from a high of 600 redds in 1982 to a low of 83 in 1996, with a fairly steady recovery of more than 200 redds in most years since then.

This year's count found that Trail Creek was the biggest producer in the North Fork drainage, with 49 redds. Coal Creek continues to be the drainage's least productive stream, with only two redds.

In the Middle Fork, the highest counts were found in Morrison Creek, with 46 redds, and Ole Creek, with 42 redds. Lodgepole Creek had the least, with just four redds. The total count of 119 redds in four Middle Fork tributaries was the highest since 1989's count of 106 redds.

This year's count was the 27th year for monitoring redds in the Swan Lake basin. Four index sections have been monitored in tributaries to the Swan River upstream from the lake.

This year, those sections had a total of 395 redds, roughly the same as the long-term average but lower than counts of 521 last year, 489 in 2006, and 489 in 2005.

Biologists have been monitoring for the potential effects of a competing lake trout population that was first detected in Swan Lake in 1998. Since then, studies have confirmed that the lake trout population has been reproducing robustly. There are concerns that the emerging lake trout population eventually will result in adverse impacts on bull trout.

This was the 16th year for monitoring bull trout reproduction in the South Fork Flathead drainage upstream from Hungry Horse Reservoir. This year's count of 74 redds in four stream index sections was about 14 percent lower than the average of 86 redds over the last 14 years.

Redd counts in the South Fork hit a low of 42 in 1995 and a high of 174 in 2006.

Reporter Jim Mann may be reached at 758-4407 or by e-mail at jmann@dailyinterlake.com