Residents of Vernal and the surrounding area may have fewer mosquitoes to swat next spring, thanks to pest-control funding provided by a multi-agency program to recover endangered fish.
In response to concerns expressed by local citizens, the top-level committee of the Recovery Program for Endangered Fish of the Upper Colorado River Basin voted Sept. 8 in Denver to make a one-time contribution of about $10,000 to the Uintah County Mosquito Abatement District.The district will use the money in spring 1995 to curb mosquito production that can accompany water releases from Flaming Gorge Dam to benefit endangered fish. The dam releases, combined with already high water from melting snowpack in the Yampa River, can force water over the banks and onto nearby flood plains, creating slow-water areas necessary for growth of young endangered fish. These same areas, however, are prime breeding grounds for mosquitoes.
"We are sympathetic to the public health concerns this situation creates for the local community, and in response, we are providing an interim source of money to address the problem," said John Hamill, a U.S. Fish and Wildlife Service biologist who directs the recovery program. "We are providing this as `seed money' for 1995 only, with the understanding that the Mosquito Abatement District will look for other funding sources for the future."
As local residents know, making a dent in the number of mosquitoes in this flood plain is no small feat. The Ouray National Wildlife Refuge holds Utah's record for collection of these tiny tormentors. During an experiment there in 1978, scientists collected more than 400,000 mosquitoes in just one night.
The Mosquito Abatement District will use the money to pay for aerial spraying along 56 miles of the Green River, from below Dinosaur National Monument to the town of Ouray. Workers will complete most of the spraying in May and June, when mosquito breeding is at its peak, and will supplement with additional sprayings as needed through August.
"During spring, the Green River is the most productive of any mosquito habitat in the county," said Steve Romney, director of the Uintah County Mosquito Abatement District. "Spraying in this area will kill hundreds of millions of mosquitoes and will make a tremendous difference to citizens."
The larvacide to be used is BTI (bacillus thuringiensis israelensis), a biodegradable, "environment-friendly" toxin that kills mosquito larvae but has almost no effect on anything else, Romney said.
"BTI acts almost exclusively on mosquitoes, does not accumulate in the environment and is recognized by environmental experts as a safe alternative to traditional pesticides," he said, The active ingredient is a "crystalline protein endotoxin" produced by commercially grown bacteria.
In addition to being annoying pests to area residents and tourists, mosquitoes can create stress in livestock and occasionally transmit certain strains of encephalitis, potentially serious viral infections that can afflict people and horses, Romney said.