Aerial pesticide spraying for mosquitoes to curb Eastern equine encephalitis virus on the South Shore will resume at sundown Sunday, officials said, after it was curtailed Saturday night because it was too cool for mosquito activity.
Crews sprayed all of Taunton and Raynham Saturday, as well as swaths of Bridgewater and Lakeville, before the spraying was called off, said Anne Roach, a spokeswoman for the state Department of Public Health.
When temperatures dip below 57 degrees, mosquitoes are less active and not as likely to fly into the pesticide sprays, she said.
“It’s more about mosquito flights than the spray itself,” she said. “It becomes less effective.”
When crews took off at 8:15 p.m. Saturday, temperatures on the South Shore were in the mid-60s, said Kim Buttrick, a National Weather Service meteorologist. The crews were called back at 9:30 p.m., before the area hit lows in the mid-50s later in the night.
The National Weather Service predicted a low of 64 on the South Shore for Sunday night.
Crews will return between 8:15 p.m. Sunday and 2 a.m. Monday to spray Acushnet, Bridgewater, Carver, East Bridgewater, Freetown, Halifax, Hanson, Kingston, Lakeville, Middleborough, Pembroke, Plympton, Rochester, and West Bridgewater.
The spray is known as Anvil 10+10, a combination of equal parts sumithrin, a pesticide, and the compound piperonyl butoxide, which activates the sumithrin.
The Department of Public Health, which is conducting the spraying along with the Massachusetts Department of Agricultural Resources, advised residents to close doors and windows, keep pets inside, and continue taking their own precautions against mosquitoes, like using insect repellant and staying indoors during nighttime.