MIDDLE TOWNSHIP — They’ve tried blasting them with pesticides, draining the swamps they breed in, infecting them with bacteria, and even employing fish to eat them, but the latest weapon in the battle against mosquitoes is barely visible.
They’re called copepods.
New Jersey delivered 10,000 of the tiny shrimp-like crustaceans Friday morning to the Cape May County Department of Mosquito Control. They’re already being used to fight mosquitoes in Bergen, Passaic and Morris counties. Ocean County is next on the delivery list and six other counties will follow.
“The days of driving a truck down the street and spraying pesticides are long gone. These copepods can pick up where fish leave off,” said Administrator Robert Kent of the state Office of Mosquito Control.
The state uses mosquitofish, fathead minnows, killifish, bluegill and other fish to combat the blood-sucking pests in larger waterways. Sometimes this involves digging ditches, not to drain the swamp as in the early days of mosquito control, but to give the fish access to the mosquitoes.
Copepods, which eat mosquito larvae but not adult mosquitoes, are meant for smaller freshwater applications such as roadside ditches, small pools, and near schools where there are strict regulations limiting pesticides.
Cape May County put some of the copepods in water-filled tires to see how they do in one of the smaller mosquito-breeding environments, but a batch was also delivered Friday afternoon to a scour hole filled with rainwater at Middle Township High School.
“Schools have to use the least toxic alternative or notify the parents. We can use them on school property without notification,” said Claudia O’Malley of the state Office of Mosquito Control Coordination.
Reducing the use of pesticides is one of the big selling points. Copepods are natural and native to New Jersey, though this is the farthest north they have ever been used for mosquito control. New Orleans was the first to use copepods, and it taught New Jersey its system of growing them in a laboratory. New Jersey is the only the second state to use them and may be the only one at this point.
“Hurricane Katrina destroyed their facility in New Orleans,” Kent said.
They are also inexpensive to produce at the state Department of Agriculture’s Philip Alampi Beneficial Insect Rearing Laboratory in West Trenton. Mark Meyer, who works in the laboratory, said it takes about six weeks to make a batch using distilled water and wheat seed as a medium and feeding them paramecium.
“To me, its way cool because I am a bug nerd,” Meyer joked.
The state Department of Agriculture is involved because mosquitoes are a vector for Eastern equine encephalitis and West Nile virus, both of which kill horses — and sometimes people.
“The public is not always aware of some of the things protecting them. This will help fight encephalitis,” state Agriculture Secretary Douglas Fisher said.
Mosquitoes have long been a pest at the shore — and the invention of the screen is credited as one of the major developments in the history of the tourism industry.
But they can also be killers. A 1959 outbreak of Eastern equine encephalitis at the New Jersey shore killed 21 people and left about a dozen with brain damage. It also decimated the tourism industry as people canceled hotel reservations and left the shore in droves, reportedly taping quarters to their windows so they wouldn’t have to open them at Garden State Parkway toll booths.
A 1968 outbreak killed six people and about 100 horses. In 1994 an outbreak killed seven horses and 10 emus. So far this year, there has only been one case. A horse in Burlington County was euthanized in May.
“We have a tourist business worth $5.1 billion (per year) in the county of Cape May. If we had a mosquito-borne illness, or outbreak, in this county it would hurt our economy,” said Freeholder Director Gerald Thornton.
Such outbreaks are relatively rare and the public has been against heavy pesticide use since DDT was banned almost four decades ago. The agencies paid to control mosquitoes are always looking for safer alternatives.
Peter Bozak, Cape May County’s director of Mosquito Control, set up a test plot with six small water holes. He put copepods in four of them and left two as control plots. He will follow the progress to see how many mosquito larvae are eaten and at what stage in their development. Mosquitoes hatch from eggs and then go through several stages towards adulthood.
The hope is birds and other wildlife will move the copepods around.
“We’re trying to use our native species and take pesticides out of the environment,” Bozak said.
Contact Richard Degener:
609-463-6711
