Do Ticks Give Deer a Bad Rap In CT?

Author: Mosquito Squad of Fairfield, Westchester, and Rockland County

Deer are one of the few wild animals that have an insect named after them, the Deer Tick. When it’s not referred to as a Deer Tick, Ixodes scapularis is also called the blacklegged tick. The term blacklegged is descriptive and distinguishes its appearance from other common ticks in CT, the Dog Tick and Lone Star Tick. Dog Ticks (also called wood ticks) and Lone Star ticks are reddish brown in color and don’t have black legs.

The primary disease spread by the blacklegged tick is Lyme Disease. Because the blacklegged tick is often called a deer tick, many believe the deer is the reason why Lyme Disease is so endemic to Connecticut. Scientists know many deer are infected with Lyme Disease in areas where it is common but the deer do not get sick from it. Deer do not give ticks Lyme Disease. The ticks get the Lyme bacterial infection earlier in their life cycle. So what role do deer play in Lyme Disease if they can’t infect ticks with it?

The introduction of game laws in the 1940’s as well as the urbanization of former farmland and wooded areas around cities in CT began to create the ideal habitat for deer numbers to increase. As deer numbers expanded and deer had to search out new feeding areas they got closer to where we live.   They also helped bring the blacklegged tick onto homeowner properties in their foraging. Deer are important in the tick’s life cycle because they are one of the few animals that can provide adult ticks a blood supply large enough to begin the next generation of ticks. Female adult ticks need the nutrients from a large blood meal to lay their eggs before their life cycle ends.

A recent story on Newstimes.com, Year-round deer hunting on private property called for, by Patricia Sesto describes the steps local towns are taking in lowering their exposure to ticks by reducing the number of deer. Starting in Wilson and New Canaan and now expanded into Redding, Ridgefield, Newton, Brookfield, Darien and Greenwich, controlled deer hunting on private property is allowed. Because of these new hunting permissions, deer numbers have been nearly cut in half in some of these towns during the program’s 10-year period.

Besides reducing deer ticks, the benefits listed for the hunting program range from a healthier deer herd by reducing over-browsing of vegetation to donated venison to local food banks. Animal activists continue to oppose the controlled hunting. Because of those who oppose it, legislation to expand controlled deer hunting in the state has been prevented, according to the Fairfield County Deer Management Alliance.

So are deer the real villains in the fight against Lyme Disease? The answer is both yes and no. Yes, deer do support adult ticks at that stage of their life cycle. However, other animals infect the tick and support them at earlier stages with their blood supply. White-footed mice are usually the animal that infects ticks during the larvae and nymph stages of the tick life cycle in CT. Ticks look for their blood meal during 3 of their life stages from any animal that can give them a sufficient size blood meal. Mice, voles, raccoons, opossums, fox, dogs, coyote all serve as meals for ticks. Deer, due to their size, can support large adult ticks better. Female adult ticks lay eggs necessary to produce the next generation of ticks. Therefore, by reducing deer we can make the hypothesis that tick populations should be lowered as well, since there would be a smaller amount of blood available. It’s an easy argument to make since tick populations increased because of increased deer populations. However, no research currently supports proof of the hypothesis that reducing the number of deer also reduces the number of ticks in an area.

While the debate continues over the effectiveness of controlled hunting, you can protect your family and yourself now. Mosquito Squad of Fairfield, Westchester, and Rockland County provides a barrier spray for your yard that eliminates ticks and mosquitoes during the warmer months of the year when these insects are most active. Late summer and fall is the time of year when nymph ticks are most active and when the most Lyme Disease cases are most reported. Nymph ticks are so small they often go unnoticed. Preventing ticks from reaching your family and pets is your first line of defense when outdoors, in your yard.