Dear HCN,
In a May article titled
“Debate rages over fish poisoning” (HCN, 5/7/01: Debate rates over
fish poisoning), very subjective views of the impacts of
fish-control chemicals antimycin and rotenone on the environment
were presented. It’s ironic that despite the article’s recognition
of the growing fears of the uninformed public toward fish-control
chemicals, it fed those fears with anecdotal accounts and
unqualified information contrary to common sense and scientific
facts.
The article reports a New Mexico rancher’s
contention that his sheep must have drunk stream water tainted with
antimycin used in a project to restore the Rio Grande cutthroat
trout. According to the U.S. Fish and Wildlife Service and
Jicarilla Apache Nation biologists, potassium permanganate was used
to neutralize the antimycin at the bottom of the treatment area. A
lack of dead fish in the rancher’s stream suggests that little, if
any, antimycin persisted that far downstream. The following spring,
two lambs were reported born dead with enlarged kidneys, but no
veterinary necropsy reports were provided. The lambs could have
died of a number of common diseases or other complications.
Antimycin quickly degrades naturally, and is easily neutralized
with potassium permanganate.
Antimycin was not
“invented” in the 1970s, as the article said; it’s a naturally
occurring substance that was discovered in the 1940s. It doesn’t
paralyze the cells of fish gills or suffocate fish and other
creatures. Like rotenone, it interferes at the molecular level with
oxygen transfer during cellular respiration. Fish are more
susceptible to antimycin than are mammals and
birds.
The article quotes an opponent of
antimycin, who states that “dumping” antibiotics into creeks is
equivalent to the widespread use of antibiotics in hospitals, and
will result in the survivors showing increased resistance to
antimycin. The portrayal that this “horror-movie scenario” will
occur from the use of antimycin in fisheries management is
completely unfounded and technically incorrect. Antimycin is not
produced by fungi (like penicillin) but by bacteria
Streptomyces, and it has no antibacterial
qualities.
Although rotenone had nothing to do
with this New Mexico “event,” the article erroneously characterizes
the Lake Davis, Calif., northern pike eradication as a failure. It
is unknown whether any northern pike survived the treatment or were
reintroduced. The article claims that the City of Portola lost much
of its water, 62 people were hospitalized, and the economy dried up
overnight, all the results of a single rotenone treatment. The
truth is less dramatic. The City of Portola lost none of its water
supply, and the California Department of Health Services in August
1998 again certified Lake Davis as a potable water supply. The
local economy was depressed prior to treatment, but it has
blossomed since the treatment, due to increased revenues from the
excellent trout fishing now present in Lake Davis. Although some
Portola area citizens went to the local hospital with health
complaints during the treatment, follow-up investigations by the
California Environmental Protection Agency concluded that none were
the result of poisoning.
The selective use of
fish-control chemicals has restored numerous populations of
threatened and endangered species of fish, including bull trout in
Oregon, golden trout in California, Apache trout in Arizona, and
many other trout populations in California, Wyoming, Colorado and
Utah. The American Fisheries Society Rotenone Stewardship Program
Web site, www.fisheries.org/rotenone, contains an array of public
and technical information on the safety of rotenone that could be
used as guidance for disclosing information on antimycin.
American Fisheries Society Fish
Management Chemicals Subcommittee,
Task Force on Fishery
Chemicals;
American Wildlands,
Federation of
Fly Fishers,
Greater Yellowstone Coalition,
Idaho Fish and Game,
Montana Fish, Wildlife, and Parks,
Montana Trout Unlimited,
Turner Endangered
Species Fund,
Wyoming Trout
Unlimited
This letter was shortened due to space limitations.
This article appeared in the print edition of the magazine with the headline The facts about fish control.
Republish our articles for free, online or in print, under a Creative Commons license.
