Suffolk County says it’s ready to battle mosquitoes this summer

Blood-hungry, disease-carrying mosquitoes—as much a part of a hot, sticky Long Island summer as a Mister Softee song or a day at Jones Beach—are back and they’re ready to bite you.

But the buzz of helicopters flying over the East End marshes on Tuesday, spraying a mixture of larva-killing pesticides, was also a sign that a worthy adversary had returned: Suffolk County Vector Control.

Vector Control crews sprayed the two pesticides — one of which is considered dangerous to certain marine life by environmental experts — on marshes in Lyman Marsh, Smith Point County Park and the Wertheim National Wildlife Refuge in Brookhaven, Napeague and Beach Hampton in East Hampton, and the West Oak Recreation Club in Islip. It was the fourth mass spraying of the year in Suffolk — an effort that began June 11.

Health risks

Mosquitoes found in salt marshes, like the one targeted Tuesday, are less likely to transmit West Nile virus than other species, Tom Iwanejko, director of Suffolk County Vector Control, said in an email. However, he noted that they can transmit other diseases.

Residents of Mastic Beach and South Shirley “call us complaining that they literally have to run to their car or mailbox and still get mosquito bites,” Iwanejko said.

The health risks are clearly visible, he added, when they “send us pictures of their children with swollen eyes closed from mosquito bites, after they come back from the hospital because their child is severely allergic to mosquito bites.”

After full and new moon tides or major storms, or about every two weeks from May through September, Vector Control teams sample water from 2,500 hectares of wetlands spread across about 70 sites, Iwanejko said.

“Only if there are mosquito larvae breeding at the site,” he said, “would we consider aerial spraying of the marsh.”

Spray from above

Pesticide-spraying helicopters play a key role in Suffolk’s seasonal battle against mosquitoes, with volunteers sometimes called in to help locate the marshes and wetlands most commonly used as breeding grounds, officials said.

Volunteers have been taking action in East Hampton during what are called “Marsh Mondays,” said Kim Shaw, environmental protection director for the city of East Hampton. For several years, volunteers have been collecting water samples in Accabonac Harbor, counting larvae and sending data to Suffolk County Vector Control to pinpoint areas where pesticides are being used.

“Mosquitoes are a real problem, especially along the Napeague area with all those big freshwater marshes,” Shaw said. “Restaurants there have a really hard time combating that with outdoor dining.”

Iwanejko said spraying designated areas by volunteers reduced pesticide use in Accabonac Harbor “significantly.” Wetland restoration projects, such as those undertaken in the Wertheim and West Sayville National Wildlife Refuges, which boosted killifish populations in marsh waters to eat mosquito larvae, also reduced pesticide use.

Environmental impact

Environmentalists have long opposed the use of methoprene, one of two pesticides the region uses to spray mosquitoes, saying it harms crustacean larvae.

In Suffolk County, a combination of two pesticides—Bacillus thuringiensis israelensis, also known as BTI, and methoprene—is used to effectively kill mosquito larvae at various stages of development.

BTI poses no threat to the environment and is even “used by organic farmers,” according to Adrienne Esposito, executive director of Citizens Campaign for the Environment. But methoprene, Esposito said, can harm marine life, such as blue crabs and other local shellfish that spawn in salt marshes.

“Wetlands are important habitat for shellfish and finfish,” she said. “We need the province to be very careful and judicious with the use and potential misuse of this pesticide.”

In Suffolk County, Iwanejko said, methoprene “is also only used in the upper high marshes and not spread into the tidal marshes or into the bay, further reducing potential contact with blue crabs and shellfish.”

He added that researchers at the Stony Brook Marine Science Center have examined methoprene and “determined it is an accepted material” for the county’s purposes, and that the pesticide has undergone “rigorous” federal and state review.

Officials and environmentalists agreed that pesticide use has improved dramatically in recent decades.

“It’s not like the old days when you’d have a truck driving down the street with spray and kids riding their bikes behind it,” Shaw said of past efforts to reduce mosquito populations.

Esposito said pesticides have become “less toxic” in recent years, but they should still be used with caution.

“Twenty years ago, Nassau and Suffolk were spraying liberally all the time,” she said. “They’ve really dialed that back. They’ve gotten more sophisticated in their methods … and I think that’s really helped the environment and the public.”