Mosquitoes are not nearly as abundant this year as last, the manager of one of the two mosquito-control districts in La Plata County, said Monday.
“We have 13 traps that we check six days a week,” said Sterling Schaaf, manager of the Animas Mosquito Control District. “On the night of July 18, 2011, we caught 1,300 mosquitoes. On the same date this year we caught 250.”
The presence of mosquitoes tells district employees where to concentrate their spraying, Schaaf said.
Fogging, as it’s called, consists of spraying a mixture of 5 parts mineral oil and 1 part permethrin, a synthetic chemical.
Truck drivers fog pools of stagnant water such as catch basins and ponds. People on a no-spray list are exempt unless there is a health crisis which, under state law, trumps personal wishes.
Last year, Schaaf said, started as the worst year for mosquitoes since 1995, when the Animas Valley flooded.
“We have two trucks fogging 23 hours a day,” Schaaf was quoted as saying in a July 10, 2011, story in The Durango Herald.
Spraying brought the hordes under control.
No one from the Florida Mosquito Control District was available Monday for comment.
The two districts split the county – Schaaf’s district covering northern and western sectors, the Florida district, the south and east.
Schaaf said he used to spray for mosquitoes in Durango four or five times a summer. But it’s not been necessary for several years, he said.
The Animas District tests regularly for West Nile virus and western and St. Louis encephalitis.
Bari Wagner, an epidemiologist at San Juan Basin Health Department, said Friday there has not been a single case of West Nile virus in the district this year.
The mosquito population has been reduced far below historical numbers, Schaaf said.
When he was growing up in the Animas Valley, at haying time, horses were swarmed unmercifully by mosquitoes, Schaaf said.
“Any horse would appear to be gray-colored because of the number of mosquitoes on it,” Schaaf said.
In 1960, voters agreed to tax themselves for mosquito control, Schaaf said.