Shelter Island is installing 4-poster units — the Island’s main weapon in countering deer ticks responsible for the spread of Lyme disease and other tick borne illnesses.
There were 14 units deployed around the Island last week, according to Shelter Island Police Department clerk Jennifer Zacha. The 4-posters are designed to coat the necks of deer with permethrin, a tickicide that rubs on the necks of the animals as they feed at the units.
Another 4-poster was expected to be placed at Sylvester Manor and Mashomack Preserve borrowed four from the town to install on its grounds this summer.
Mashomack workers will maintain these four stations and will reimburse the town for the costs of permethrin as well as corn to attract the deer.
“We also have approval for three additional units for the town if more funds become available,” Ms. Zacha said.
Shelter Island allocated $75,000 in its current budget for this year’s deployment, the same amount as in 2012. But late last year there were town residents who indicated they would allow 4-posters on their land at their expense. By the time the town obtained New York State Department of Environmental Conservation approval, it was too late to place the additional units, Supervisor Jim Dougherty said at the time.
This year’s deployment came about a month earlier than last year when Highway Department employee Nick Ryan, trained and licensed to use permethrin, had to wait until May to get the DEC go-ahead. Optimal time for deployment is considered to be in March and April, according to DEC officials..
This is the second year that the town has totally absorbed the cost of deploying the units. Prior to that, Shelter Island had been part of a three-year Cornell University and Cornell Cooperative Extension study that started in 2008 to assess the effectiveness of the units.
While there is no data from the Suffolk County Department of Health Services to verify that the 4-posters are effective in curbing the spread of tick-borne diseases. But anecdotally many Islanders believe they’re worth the investment.
Still, the deployment remains controversial. Some residents argue 4-poster use results in polluting well water as permethrin runs off the units. Those who favor the use of the units argue that drag testing around 4-poster sites shows fewer ticks than were detected before the deployments started and fewer incidences of illness.
Critics such as Richard Kelly counter that no recent statistics prove the incidence of tick-borne diseases has decreased. Mr. Kelly sees the money spent on the units as a waste and argues that permethrin is a danger once it enters well water.
Members of the town’s Deer and Tick Committee have been quick to dismiss Mr. Kelly’s charges. And DEC officials say their studies show there’s a greater incidence of permethrin in runoff water as a result of aerial spraying than what the tickicide being put on the 4-poster units.
Representatives of the DEC, who were slow to come to the table in support of the use of 4-posters, have become strong supporters, even sending representative Vincent Palmer to push the program with the North Haven Village Board last year. But that board has, so far, balked at instituting the program, largely because of the cost.
North Haven was the control site when Shelter Island participated in the Cornell study.
Cornell Cooperative Extension educator and entomologist Dr. Dan Gilrein has said nobody has a clear idea of what factors affect the tick population. He speculated that 20 years from now there would be more definitive information resulting from ongoing studies. He also noted that during the time North Haven was the control site for the Shelter Island site, that village experienced a downturn in ticks even without 4-posters.
A mild winter such as 2012’s gives ticks more opportunities to find deer hosts, Dr. Gilrein said at the time.
“The weather could trump everything,” he said. He credits Shelter Island with taking the initiative to continue the 4-poster program in-house now that the Cornell experimental program has ended.