Small dead sparrow lying on grass in a garden | Alex Rogals

A number of dead birds in Oak Park has caused confusion and concern among village residents. Not flattened by cars, the carcasses appear to have belonged to outwardly healthy-looking birds. What’s killing Oak Park’s birds is West Nile virus-carrying mosquitoes.

The same irritating creature whose bites result in itchy, red welts is also an avian grim reaper, causing birds to drop dead left and right.

This summer’s weather conditions resulted in a growing population of the Culex mosquito, the species native to the area, which led to more mosquitoes picking up West Nile from invasive species carrying the virus, according to Susan Wolf, an environmental health professional employed by the Oak Park Public Health Department.

We’ve had a number of invasive species that have traveled over here to the United States,” said Wolf. “That’s how [the virus] gets transported

Susan wolf

“We’ve had a number of invasive species that have traveled over here to the United States,” said Wolf. “That’s how [the virus] gets transported.”

The West Nile virus is then transferred into the blood streams of birds through mosquito bites. Mosquitoes carry the higher amounts of the virus in early fall, resulting in a greater number of bird deaths in late August.

The health department turned to fogging, spraying a chemical solution in areas crowded with mosquitoes. The village utilized the services of Clarke Mosquito Control, which bills itself as an environmentally sustainable resource for mosquito abatement.

Clarke used the dual action adulticide DUET, which consists of both sumithrin and prallethrin. The chemicals are only harmful to mosquitoes, not humans or animals, according to Wolf. Fogging was completed Sept. 1

The Oak Park Public Health Department has been tracking the spread of the West Nile virus through the collection of dead birds, which are then sent to a diagnostic lab at the University of Illinois Urbana-Champaign for testing.

The biologists send weekly updates regarding the sample testing to the village. Lately, the reports have indicated a decline in the mosquito population, which is likely to cause a decrease in the number of West Nile-related bird deaths.

“The numbers are coming down,” said Wolf.

As the health department is no longer collecting dead birds, it is up to the resident to dispose of corpses found on their property by tossing them into trash bags, which should then be tied closed. People can also bury them. To prevent the spread of disease, Wolf cautions residents to always wear gloves when removing carrion.

“Never touch the animal,” said Wolf.

For dead birds found on village-owned property, people should contact the Public Works Department. Public Works is not responsible for removing deceased animals found on private residences. However, if residents find a way to nudge the carcass onto public property, Public Works Director John Wielebnicki told Wednesday Journal, his department will come to remove it.

“I’m not going to split hairs here. We try to help people,” he said. “If you get it out to the street or the alley, we’ll pick it up.”

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