New York City's Health Department announced Wednesday that it will begin its first aerial spraying of the season to reduce mosquito activity and the risk of West Nile virus beginning June 1.

The spraying by a low-flying helicopter will occur over marshes and other nonresidential areas of the Bronx, Brooklyn, Queens and Staten Island.

The Health Department said environmentally friendly and Environmental Protection Agency-approved pesticide will be sprayed on mosquito breeding grounds when appropriate throughout the season.

Spraying will occur from Tuesday, June 1 to Thursday, June 3 from 6 a.m. to 7 p.m., weather permitting. The department added that while three days are allotted for spraying, it may be completed in less time.

In case of bad weather, aerial spraying will be delayed until from Friday, June 4 and Monday, June 7 to Tuesday, June 8 during the same hours.

The department said it monitors mosquitoes that carry the West Nile virus and that to date, no human cases of West Nile virus have been reported this season.

According to experts, mosquitoes can breed in still water that has been standing for more than five days during warm weather. Existing hot and wet weather conditions can cause a rise in the mosquito population.

The department encourages New Yorkers to eliminate any standing water from their properties, dispose of containers that can collect water, mosquito-proof their homes and take precautions when spending time outdoors.

New Yorkers are also encouraged to report standing water by calling 311 or visiting nyc.gov/health/wnv.

For more information about West Nile virus, call 311 or visit nyc.gov.