Douglas County Mosquito Control will be distributing a small fish, the gamusi affinis or mosquitofish, in its fight against the spread of West Nile virus.
"Right now we have a small supply," said Ron Lynch of Douglas County Mosquito Control. "We're getting them from Yerington. They breed naturally there in a hot springs and they're very tough."
Used extensively throughout the world by mosquito control agencies, a single adult mosquitofish can eat up to 500 mosquito larvae a day. A member of the guppy family, the female mosquitofish are livebearers. Females grow to just over two inches in length and males are slightly smaller.
Normally six to 10 fish are sufficient to stock an average-sized pond. The high reproductive potential of the mosquitofish will overcome future problems with mosquito larvae, but where large number of mosquito larvae exist, fish may be insufficient in controlling them, according to information from the San Mateo Mosquito Abatement District in San Mateo, Calif.
"In such cases, it may be necessary to clean the pond or to have the District treat it with environmentally safe insecticides prior to planting mosquito fish," they said.
There is no permitting process through the Nevada Department of Wildlife. The fish are not native to Nevada but they're not considered invasive, according to Chris Healy, spokesman for the Nevada Department of Wildlife.
"In most cases we demand that the fish be sterilized, but these (fish) are doing some good," Healy said. "Mosquito control is a big issue, and not just because they're annoying. This is a nice, natural way to battle something like West Nile."
In addition to the fish, Lynch is distributing Altosid tablets in standing water around the county. The hormone prevents mosquito larvae from maturing.
Trapping mosquitoes to test for West Nile virus has not begun, Lynch said.
"We're watching the temperatures and we won't start trapping until it warms up," he said. "We'll probably start some time in May."
A mosquito-borne disease that originated in Africa, West Nile has now established itself throughout the continental United States. In Nevada the number of human cases increased dramatically, from 30 cases in 2005 to 123 cases in 2006.
The disease is usually characterized by mild flu-like symptoms. More severe cases, which occur in about one in 150 people, can cause everything from high fever to vision loss, numbness and paralysis. The neurological effects may be permanent, according to information from the Centers for Disease Control and Prevention in Atlanta.
Susie Vasquez can be reached at svasquez@recordcourier.com or 782-5121, ext. 211.
BREAKOUT
County efforts to eradicate mosquitoes are important, but just part of the solution. Residents play an important role in controlling the spread of West Nile by destroying any breeding sites around their homes, according to information from the Environmental Protection Agency.
The following is a set of guidelines, published by the Agency.
• Eliminate standing water in rain gutters, old tires, buckets, plastic covers, toys, or any other container where mosquitoes can breed.
• Empty and change water in bird baths, fountains, wading pools, rain barrels, and potted plant trays at least once a week to destroy potential mosquito habitats.
• Drain or fill temporary pools of water with dirt.
• Keep swimming pool water treated and circulating.
