Wayne Rowley has found increasing use for his research lately, as mosquito numbers climb and the West Nile virus continues to be a threat.

“There are significantly high numbers of mosquitoes this year,” said Sara Erickson, research assistant in Rowley’s lab.

Erickson, graduate student in entomology, monitors the numbers and species of mosquitoes collected from 11 sites located across Iowa.

The researchers go out into the field three or four nights a week, collect the sites’ traps and bring back the mosquitoes to count and identify them, she said. There are two traps in Ames.

Rowley, professor in entomology, was not available for comment.

The researchers send weekly reports to the city on the numbers of mosquitoes in the area.

“When mosquito numbers advance, we fog,” said Kevin Anderson, city sanitation.

The city fogs in eight Ames parks, including Inis Grove and Brookside, according to the City of Ames Web site, www.city.ames.ia.us.

Fogging, spraying to control mosquitoes, occurs once a week from 8 p.m. to 10 p.m. when mosquito activity is highest, Anderson said. They use a low volume pesticide called Mosquito Mist, he said.

“We do not spray the foliage,” Anderson said. “The mist has no residual, so it has to hit [the mosquitoes].”

Foggers also attack larvae and check sites that are ideal for mosquitoes to breed, such as low areas that hold water, he said.

Patricia Quinlisk, epidemiologist for the Iowa Department of Public Health, said they are advising communities to implement mosquito foggings.

“No program, however, will get rid of every mosquito,” she said.

The department is recommending a number of preventive practices people can take to protect themselves, including not going out at dawn or dusk, applying insect repellent and securing windows with screens, Quinlisk said.

The number of mosquitoes have increased this summer because of the perfect breeding conditions this spring, Erickson said. “We had a warm spring allowing the females to lay eggs outside earlier and amplifying the mosquito population a lot earlier,” she said.

The lab is finding high numbers of mosquitoes belonging to the Aedes genus in the traps. These mosquitoes feed on mammals and are most likely to bite people, she said.

However, it is the Culex genus that raises the most concern to the researchers. This type of mosquito feeds on birds and is mostly responsible for the spread of the West Nile virus.

“When it can’t feed on a bird, it finds a mammal instead,” Erickson said.

When the Culex mosquito feeds on mammals, including horses and humans, it can spread the virus.

Erickson said the lab also monitors the amount of mosquitoes laying eggs. She said those numbers have dramatically risen recently. This is due to the higher amount of adult females surviving the winter causing them to lay more eggs, she said. Now, they are seeing that generation laying their eggs.

“The numbers of eggs are doubling and even tripling,” Erickson said.

The high numbers of mosquitoes are expected to continue until the weather changes. “The numbers will slow down only when it starts to get hot and dry,” Erickson said.