2018 State of the Beaverhead Watershed

Beav bow/photo by my late friend, Dick Moore, who caught it and shot the photo

Recently the Lewis and Clark Chapter of Montana T.U. met as always at the Anderson and Platt Fly Shop just outside Dillon.

Matt Jaeger, FWP Fisheries Biologist, presented an overview of the ongoing work to protect and enhance what’s left of the native westslope cutthroat trout population within the Beaverhead and Ruby river watersheds.  In brief the process begins by identifying genetically pure populations thru state of the art DNA analysis. The next step is to identify streams with either a natural block to upstream migration or to identify a spot suitable to build a man-made block. Man-made blocks are not cheap so funding becomes a major hurdle.

The main culprit to maintaining genetically pure populations is thru hybridization with love to hate (or much loved, depending) rainbow trout. Rainbows are great travelers as researchers found out in assessing the potential dangers the proposed Black Butte Mine might pose with Smith River trout.  To their surprise not only do Smith River rainbows spawn in Sheep Creek (mine site) but so do some Missouri River bows—BTW a 400 mile round trip.

The ongoing debate on how best to protect and enhance the fluvial grayling population in the Red Rocks National Wildlife Refuge. Several years ago refuge managers determined the Yellowstone  cutts were simply eating the grayling to extinction. Kill the cutts. Problem solved...Not so fast. Despite killing hundreds, maybe thousands, through extended, high-creel limit, fishing seasons, in conjunction with in stream traps, grayling numbers continue to crash.

Meanwhile Matt and crew had pretty much concluded cutts were not the culprits and put the blame on degraded/non-existent spawning habitat largely due to siltation from loss of scouring flows enough to clean spawning gravels and a calamitous loss of over-winter habitat due to a severe drop in oxygen levels in Upper Red Rocks Lake.  Snow cover drives oxygen levels in the the lake—too much, for too long oxygen takes a dive.  Beaver dams prevent scouring of spawning gravels. Only way to help the lake situation is make it deeper (cost prohibitive) but breaching the beaver dams, increasing the flow, scouring the spawning gravels is a possibility. Matt and his crew plan began last spring breaching the dams and have three more years to see what happens.  Refuge managers are apparently not convinced so how this one will play out remains in limbo.

Clark Canyon Reservoir’s recent crash of big fish (8-10 lbs. plus) is due mostly to a decline in the quality of Eagle strain rainbows produced by the Ennis National Fish Hatchery. The hatchery supplies fish to, I think, 13 states and except for Matt none are interested in anything but put and take fisheries...Sad but true, the only solution is to somehow get enough from the source, Eagle Lake, California...Matt is on the  track but still not sure how will work out.

Last season the Beaverhead recovered some from the combination of a too low overwinter flow and an out of balanced population of mid-size fish crowding out the big boys and girls. This winter flows are up some somewhat reducing the overcrowding situation and with the reservoir expected to fill decent flows should continue.  The consensus of guides and outfitters in the room suggested low trout numbers below Hildreth Bridge; Matt’s electroshocking survey did not agree. My take (and that of a couple fellow guides) was at first seemed to agree with the above consensus but once the flow stabilized seemed trout, many of decent size were everywhere in the Henne-Hopper section.  For what it’s worth, I could hardly buy a fish between Hildreth and Henne the few times I guided it. About 2600 trout per mile live in the upper river.

The Ruby: Numbers (about 1600 per mile) and size of brown trout from the dam to Silver Springs was about average; below Silver Springs not so hot.  In my experience and those of the guides I work with the numbers are spot on... Less water due to irrigation demand is the likely culprit. Hopefully something like a drought management plan can be worked out with ranchers and farmers to maintain a more friendly flow regime. Keep your fingers crossed.