Environment DEC
From the June 2007 issue
DEC Treats for Sea Lampreys on the South Fork of the Ausable River
Lamprey control chemicals are sprayed into a stream over a 12-hour period
In late May, New York State Department of Environmental Conservation (DEC) treated the South Fork of the Ausable River, a tributary of Lake Champlain, for sea lampreys. The treatment was a continuation of a long-term effort to protect the lake's fishery from the parasitic fish.
Trout, Salmon and Other Gamefish Benefit
The Ausable River was previously treated in September 2006. Post treatment sampling indicated that an estimated 80,000 sea lamprey were left in the South Fork of the Ausable River. DEC determined that low flows at the time of the treatment prevented an effective concentration of the sea lamprey control chemical from entering the South Fork of the river. Therefore staff from DEC, the Vermont Department of Fish and Wildlife, and the U.S. Fish and Wildlife Service decided to treat a two-mile length of the South Fork again, before larval lamprey transform into their parasitic stage. Trout, salmon, and other fish populations native to Lake Champlain will benefit from this action.
Residents in the treatment area were notified prior to each treatment and temporary water use advisories were implemented to minimize human exposure to treatment compounds. The State Department of Health recommends that the treated river and lake water not be used for drinking, swimming, fishing, irrigation or livestock watering for the short period that lamprey control chemicals are present.
In the Lake Champlain system, most immature sea lamprey live in streams for four years before descending into Lake Champlain to prey on other fish like trout and salmon. Under the sea lamprey control program, a pesticide, TFM (trifluoromethyl-nitrophenol), is applied in precise concentrations to streams in a continuous, metered manner over a period of approximately 12 hours in order to kill the immature, larval form of sea lamprey.
The Economy Benefits Too
DEC studies have shown that sea lamprey control results in decreased wounding and scarring rates to other fish and can increase populations of lake trout and landlocked salmon. Surveys of anglers showed that more and substantially bigger trout and salmon were caught as a result of the previous treatment program.
Sea lamprey control also improves the economy as angling opportunities increase. According to the study, Benefit Cost Analysis of the Eight-year Experimental Sea Lamprey Control Program on Lake Champlain, by Alphonse H. Gilbert, a researcher from the University of Vermont, sea lamprey control generated benefits of approximately $29.4 million with costs of about $8.4 million. These benefits were the result of the increased number of boaters and anglers spending longer periods of time in the Lake Champlain area.
DEC has set up a toll free number (1-800-638-5432) for the public to obtain information on the lamprey treatments. Callers can receive information on the treatment schedule for the specific waters, progress reports, updates on treatments and water-use advisories.
