After reading the following information on ROTENONE used to rehabilitate lakes, please answer a few questions. This information is furnished by the Washington & Oregon Dept. of Fish & Wildlife.

What other uses are there for rotenone?
Rotenone is used as a garden insecticide to control chewing insects, has been used as a dust on cattle, and is used as a dog and sheep dip, in addition to its use as a fish control agent.

How does it work?
Rotenone does not "suffocate" fish as was long believed. Instead, it inhibits a biochemical process at the cellular level making it impossible for fish to use oxygen in the release of energy needed for body processes.

Rotenone Use Background

Number of Waters Treated
The first rotenone treatment in Washington State took place in September 1940 on Kings Lake (Pend
Oreille County). Since that time WDFW has treated 508 state waters at least once. The chlorinated
hydrocarbon insecticide toxaphene was occasionally used instead of rotenone. Its use was discontinued in the late 1960's because of problems experienced with persistence of residues that killed planted trout fry (WDFW historic data). Since then, rotenone has been the only piscicide applied by the agency.
Almost all treatments have occurred in lakes and ponds, with only occasional stream or slough
treatments. The 508 waters treated since 1940 represent 6.1% of the total surface acreage of all lakes below 2,500 feet elevation in the state.
Since 1992, rotenone treatments have taken place in eight eastern Washington counties: Adams, Ferry, Grant, Lincoln, Okanogan, Pend Oreille, Spokane, and Stevens. One western Washington water was treated in 1998 (Crocker Lake, Jefferson County) to eliminate illegally planted non-native northern pike as a measure to protect Endangered Species Act listed juvenile salmon from unnatural predation. One hundred eleven waters have been treated, five twice since 1992. Most (71.6%) of these eastern Washington waters were located on public lands (primarily WDFW controlled lands). The average size of the waters treated is 59.8 surface acres. On average 13 waters were treated each year with an average 79,500 pounds of powder and 440 gallons of liquid formulation rotenone.

Frequency of Rotenone Treatments
Rotenone treatments do not always kill all the fish in a lake. Problem species are also
reintroduced illegally by anglers or lakeside residents. The appearance of species different from the ones that originally degraded the target fishery is evidence of this (WDFW historical record). Problem species that survive repopulate the lake over time. The net result of any of these cases is the same: fish growth and quality will eventually decline, and the lake may have to be rehabilitated again.
Of the 508 Washington lakes that have been treated, 283 (55.7%) have been treated more than once.
The average length of time between treatments has been 7.74 years.

I think that this poll is great to get an idea of how the fishermen feel about rotenone as a rehabilitating agent.

I would like to mention that there has been no alternative found to rotenone that is as effective in cost or time or end result. Rotenone is not perfect but as long as we have to deal with illegally stocked lakes and the scum that give no heed to the consequences we have to stick with it.

Thanks for the update on Rotenone....one thing stood out to me was that the # of lakes affected certainly was less that I thought!