Experiments could reduce the dangers of ticks

KENT — Critters large and small begin to emerge from their winter hiding places with the warmth of spring — and some of those critters are  ticks.

In a talk sponsored by the Kent Land Trust on  Friday, March 24, at Town Hall, Mike Benjamin and Joshua Ginsberg spoke about how ticks find us, how we can reduce the risk of disease, and steps being taken to control them.

Benjamin, who is land manager for the Kent Land Trust, described the biology and ecology of deer ticks, which are the most common species in northwest Connecticut. 

Tick are able to withstand frigid temperatures, so the notion that cold winters kill them is false. They are active year-round. 

“If it is a sunny winter day above 30 degree Fahrenheit, expect ticks to be out and about,” Benjamin said.

Their typical life cycle spans two years. 

“Each female tick can lay 2,000 to 3,000 eggs in the spring” Benjamin said. “The larvae then hatch in late summer. If they successfully feed on a host, they molt into a nymph and can lie dormant until the following autumn when, after another successful feeding, they become adults.”

Ticks feed on the blood of animals. They do not have eyes, so they rely on chemical receptors on their two front legs that sense humidity and carbon dioxide levels to find a host. They climb onto vegetation and wait, front legs outstretched, for an unsuspecting creature to pass by. 

“Ticks do not jump or fly. They are a  sit-and-wait predator,” Benjamin said. Once a tick has found a victim, it pierces the skin using a harpoon-like structure with backward facing barbs to draw out blood.

Ticks can become infected with or transmit a disease at any point during their life cycle. In the adult stage, however, only females can transmit disease. In addition to Lyme disease, ticks are vectors of Babesia, Anaplasma, and Powassan. A tick can also transmit more than one disease to its host, with a co-infection rate of about 30 percent.

Ginsberg, who is president of the Cary Institute of Ecosystem Studies in Millbrook, talked about a study called The Tick Project that is ongoing at the institute. Its goal is to look for environmental interventions that can help reduce the tick population, and thereby reduce the incidence of tick-born diseases. 

Dutchess County, where the institute is located, has one of the highest Lyme disease infection rates in the nation, he said.

Two interventions will be tested this year. The first is a fungus that kills ticks called metarhizium anisopliae, or Met52. With the help of a pest control company, this fungus will be sprayed on yards of volunteer property owners. 

The second is the use of bait boxes. Mice are good at harboring diseases, and even better at passing those diseases to ticks. If a tick bites a mouse that is carrying a disease, there is a 90 percent chance the tick will become infected. 

In contrast, if a tick bites an infected deer, there is only a 10 percent chance the tick will become infected. 

These bait boxes will contain a treat to lure in mice; a tool inside the box will apply a dose of the insecticide fipronil — the active ingredient in Frontline. 

Preliminary testing of both methods has already proved successful.  

Both Benjamin and Ginsberg emphasized that the most effective way to mitigate the risk of contracting a tick-born disease is to regularly check yourself and your pets for ticks after being outside. 

“The sooner you find and remove a tick, the less chance you have of becoming infected with a disease,” Benjamin stressed. “Be sure to have a sharp pair of tweezers or a tick remover on hand,” Ginsberg said.

To learn more about The Tick project, go to www.tickproject.org.