New Weapon in the Deer Tick War
Feeders that rub chemicals on hungry deer
Target the loathed bloodsuckers
(05/21/2009) Deer ticks and their potential for transmitting Lyme disease have become such an accepted part of daily life on the East End that it is not uncommon to hear of people getting multiple cases per season.
 Cornell Cooperative Extension
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Other tick-borne diseases such as babesiosis and ehrlichiosis have also become prevalent.
As a result, residents have armed themselves with Frontline for their pets, ordered tickicides to be sprayed all over their lawns, invested in high white socks for hikes in the woods, and employed a variety of other strategies for warding off ticks.
There is another option, however, one that has been approved for use in every other state in the country that has similar problems with ticks. It is called a 4-Poster deer feeder, and the Cornell Cooperative Extension is now testing it on Shelter Island.
If the project, which is in its first year, proves successful after a few more years of study, it is possible that the New York State Department of Environmental Conservation will approve the feeders as an alternative to the “broadcast sprays of permethrin so common in landscapes now,” according to Dan Gilrein, an entomologist at the Cornell Cooperative Extension of Suffolk County. “It may also inspire further research on other alternative host-directed controls for ticks using materials other than permethrin.”
What the department hopes to address in the study is whether the feeders alter the movement or behavior of deer in a negative way and if they lead to increased human exposure to permethrin through handling and consuming of treated deer. The study also aims to find out if the deer population would increase with the introduction of a regular food source.
Susan Walker, a biologist who is serving as the project coordinator for the extension, has tagged deer on Shelter Island and North Haven to compare their movements. There is an expectation that deer will stay in one place once they have identified a constant source of food. Deer now tend to move around Shelter Island and have been known to migrate to North Haven and Southold.
There is also an expectation that deer might reproduce more if they are better fed and healthier. “It’s a balancing act between ticks and deer,” Mr. Gilrein said.
The Suffolk County Department of Health Services, which is also participating in the study, has monitored water to make sure the pesticides used are not getting into the water supply.
Mr. Gilrein said in a talk with the Southampton Town Conservation Board earlier this month that the department has never detected permethrin in the groundwater but would like to see other options, such as pheromones, considered in combating the tick population.
The 4-Poster feeders have a small trough where deer can access corn or whatever else is placed inside. As they do, their heads and necks rub against rollers that have been treated with the permethrin tickicide, which will kill the ticks that gather there.
Studies supporting the program have shown that up to 98 percent of a tick population can be killed over a three to four-year period using such a system. In states where the feeders are allowed for residential use, a professional service applies the tickicide and the homeowner fills the feeder.
In the study’s first year, there has been little conclusive evidence, but nothing negative about the feeders has come up. The Department of Health Services did find low levels of permethrin in some deer meat samples, but the levels apparently were not high enough to cause concern. The Environmental Protection Agency has approved the chemical for use, but notes on its Web site that it is highly toxic to aquatic organisms and to honeybees and other beneficial insects.
The amount of permethrin used in lawn applications on Shelter Island over the course of three years is about 200 pounds, Mr. Gilrein said, basing the number on the records of suppliers. He added, however, that that figure is probably an understatement because of unreported or illegal applications. He estimated that the amount of the chemical applied over three years through the project’s 50 feeder stations would be about 20 pounds per year.
Even if the data support approval of the feeders, Mr. Gilrein said they would not be part of a regionwide effort. The cost of the feed and the application of the pesticide would be too great for most homeowners, he said, and there would be setback requirements. On Shelter Island, most of the feeders are on public land.