Daily News Archive

Boulder, CO Opts Not To Spray for Mosquitoes
(Beyond Pesticides, Septmeber 2, 2003)
Because mosquito traps set within the city limits of Boulder over the past week have shown very low numbers of the vector mosquito species Culex pipiens and Culex tarsalis, that are known to carry the West Nile virus (WNv), the city decided not to spray, according to an August 28th city press release. Data from traps set for one night showed a total of 78 mosquitoes, 12 of which were the target species.

"In order to consider spraying, we are looking for a high number of trapped mosquitoes and then a high percent of those being the vector species," said Alice Guthrie, integrated pest management coordinator for the city of Boulder. "We think that the larval treatment that we have been conducting since earlier in the season may be contributing to the low numbers."

The city will continue setting traps within the city and if high concentrations of the WNv-carrying mosquitoes are discovered, a spray will be planned for that target area. Residents will receive phone notification 48 hours in advance if the spray is planned for their area. Residents can choose to opt out of the spray on their property by calling a city hotline number.

According to the Rocky Mountain News, county health departments have been urging Boulder, along with other municipalities to spray. Yet, "[h]undreds of Boulder residents have told officials they prefer the risk of West Nile fever to the risk of pesticides."

A letter to the Colorado Daily editor by a Boulder resident thanked "the city of Boulder for their conscientious preventative approach" to the West Nile virus problem in Colorado this summer. The resident wrote of her concern with the pesticide product that is being used elsewhere in the county, citing research done by David Pimentel, Ph.D. professor of entomology at Cornell University, about the ineffectiveness of sprays reaching their target pests and a study in New York that showed an increase in mosquitoes due to 11 years of repeated applications.

For more information on Boulder's mosquito management program, contact Alice Guthrie, environmental affairs at (303) 441-1915 or http://www.ci.boulder.co.us. For additional information on mosquitoes and West Nile virus, see Beyond Pesticides' program page.