The Northern California Fly Fishing Board

sent to me by Bob Baiocchi...Thanks Bob

This information is avalible at

http://www...davis/projectupdate.html

Lake Davis - Northern Pike Eradication Project

Lake Davis Pike Eradication Project Update
September 25, 2007 10:00 P.m.
Portola Field Office
Project Information Line: (530) 832-4754


The California Department of Fish and Game (DFG) began treatment of the waters of Lake Davis on Tuesday Sept. 25. About 25 boats, including three air boats, began applying rotenone to the reservoir at about 7:30 a.m. after water flows from Grizzly Valley Dam were shut off. Each boat used a pumping system and GPS (global positioning system) to apply the proper amount of the rotenone to sections of the reservoir.

Resources Secretary Mike Chrisman, California Department of Fish and Game Acting Director John McCamman, Project Manager Ed Pert, and several members of the Lake Davis Steering Committee were on hand to discuss the project with over 30 members of the media.

At the same time as the treatment of the reservoir, field crews were conducting a second treatment of the tributaries flowing into Lake Davis. This stream treatment uses 5-gallon drip stations in flowing water, while crews using backpack sprayers and trailer-mounted spray rigs treated standing water and backwater areas. Special drip stations and mechanical barriers were set up at the mouths of the tributaries to prevent any fish from moving up from the reservoir.

By mid-morning, many pike and other fish in the reservoir had washed up on the shore. Later in the week, DFG crews will be netting and picking up dead fish which will be taken by a Plumas County waste disposal company to a Nevada landfill. The dead fish pose no danger to wildlife, such as herons and coyote, which are scavenging in the area. The water is safe for wildlife to drink.

Grizzly Valley Dam will remain shut off for up to 45 days to allow the compounds to degrade naturally in the reservoir. Below the immediate dam area, spring flow and incoming groundwater will help feed the creek and provide sufficient habitat for fish in the creek.

The U.S. Forest Service closure is still in effect, with check-in points to the project area on Grizzly Road and the upper end of West Street. Please contact Lori Wood at (530) 394-8027 or (530) 836-7171 if you live within the project area and have not yet obtained a pass for your vehicle. Passes can also be obtained from the Beckwourth Ranger District Office.

Post-treatment stocking will begin when Lake Davis is free of any of the rotenone formulation compounds, which is anticipated to occur before the reservoir freezes over. The majority of the stocking will occur in Spring 2008, with several hundred thousand fingerling, sub-catchable, catchable, and bonus size rainbow trout, along with fingerling brown trout.

In addition to the information provided in the EIR/EIS for the project, an analysis of the seven lots of rotenone being used in the project has been conducted. The information is available at www.dfg.ca.gov/lakedavis. Information on project monitoring results will be posted on the Lake Davis website as they become available.

Project Information kiosks are set up in the Portola area at Leonard’s Market, Portola City Hall, Portola Post Office, the DFG Office at 209 Commercial Street, Crocker Station on Grizzly Road, Grizzly Store and at the checkpoints on Grizzly Road and West Street. In addition, updates will be posted on the web at www.dfg.ca.gov/lakedavis. For further information call the Project Information Line at (530) 832-4754.

My question: If they plant prior to the lake freezing over will there be any reliable food source for these planted fish to carry them through ice out?

My Question - I have not followed this too closely, but in the articles I've read I've only seen it mentioned that they are treating the streams twice with rotenone. If they really want to do a thourough job, I'd think they would shut down the lake and treat it several times, "just to make sure", as well as a continuous treatment of any inflow...

I don't think it would take too long to get the aquatic food chain back in order for the next planting (prior to ice-over). Nature has a way of replinishing itself...

CB

My understanding is that Rotenone only affects the fish. Every other organism including non-fish food sources, should be OK. That would include scuds, insect nymphs/larvae, snails, etc.

I think you are right...I think I read somewhere that it only affects critters with gills? I guess some aquatic bugs have gills...do scuds and snails have gills???

CB

[b]This may not be the end all be all, but was the first hit that came up on Google search of "Invetebartes Rotenone". I always heard that rotenone killed most stream life, but that was hearsay This may not be the end all be all, but was the first hit that came up on Google search of "Invetebartes Rotenone". I always heard that rotenone killed most stream life, but that was hearsay [/b}

mike

Presented at the North American Benthological Society Annual meeting, Athens, Georgia, 2003 in Disturbance Ecology

Short-term effects of antimycin and rotenone on invertebrates in first order, high elevation streams.
K.M. Cerreto1, R.O. Hall, Jr.1, and H. Sexauer2. 1Department of Zoology & Physiology, University of Wyoming, Laramie, WY 82070, 2Wyoming Game & Fish Department, Region 1, Pinedale, WY 82941

A number of native fish restoration programs are being conducted in the western US by removing non-native fishes with piscicides and restocking with native cutthroat trout. Antimycin and rotenone are regularly used due to their high toxicity to fish and low toxicity to non-aquatic organisms. Although the effects of antimycin and rotenone on fish are well understood, little work has looked at the effect of these piscicides on non-target aquatic organisms, such as benthic invertebrates. We examined impacts of antimycin and a combination of antimycin and rotenone on benthic invertebrates in several high elevation (approximately 2,400m) streams in Bridger-Teton National Forest, in western Wyoming. We examined invertebrate drift during piscicide additions and in the benthos before and after piscicide additions. Rotenone additions dramatically affected invertebrates, causing massive drift within a few minutes. Antimycin alone seemed to have little to no effect on invertebrates, with drift rates not substantially different than control sites during the antimycin addition. We did not observe major invertebrate reductions in the benthos after antimycin addition. Antimycin alone appears to have little short-term effect on invertebrates in high elevation streams.

[b]This may not be the end all be all, but was the first hit that came up on Google search of "Invetebartes Rotenone". I always heard that rotenone killed most stream life, but that was hearsay This may not be the end all be all, but was the first hit that came up on Google search of "Invetebartes Rotenone". I always heard that rotenone killed most stream life, but that was hearsay [/b}

mike