The Medfield Lyme Disease Study Committee recently hosted a representative from MassWildlife, the Massachusetts Division of Fisheries and Wildlife, in an effort to learn what the town can do to reduce its incidents of Lyme disease.
The meeting included members of the Board of Selectmen, Conservation Commission, Board of Health, as well as the Town Administrator and the Chief of Police.
It also included the Norfolk Hunt Club, Trustees of Reservations, and the Dover Board of Health, which has asked surrounding towns to join in its effort to reduce the spread of Lyme disease through controlled deer hunts and other means.
“What stood out was that only 23 deer were taken in Medfield last year,” said Christine Kaldy, Chairman of the Lyme Disease Study Committee and organizer of the joint meeting, referring to statistics shared in the MassWildlife presentation. “That, to me, is disappointingly low for dealing with the growth. That’s why we’re having such a problem with deer because the current hunting situation doesn’t come close to what we need to control the numbers.”
According to the Center for Disease Control, blacklegged ticks, which carry the disease, live for two years and have three feeding stages: larvae, nymph, and adult. Tick eggs are laid in the spring and hatch as larvae in the summer. Larvae feed on mice, birds, and other small animals in the summer and early fall. When a young tick feeds on an infected animal, the tick takes bacteria into its body along with the blood meal, and it remains infected for the rest of its life. After this initial feeding, the larvae become inactive as they grow into nymphs. The following spring, nymphs seek blood meals in order to fuel their growth into adults. When the tick feeds again, it can transmit the bacterium to its new host.
Usually the new host is another small rodent, but sometimes the new host is a human. Most cases of human illness occur in the late spring and summer when the tiny nymphs are most active and human outdoor activity is greatest. Adult ticks feed on large animals, and sometimes on humans. In the spring, adult female ticks lay their eggs on the ground, completing the life cycle. Although adult ticks often feed on deer, these animals do not become infected. Deer are nevertheless important in transporting ticks and maintaining tick populations.
“From a biological perspective, what we can say is: decreased deer equals decreased tick population equals decreased risk of infection,” said Sonja Christensen, MassWildlife Deer Biologist and project leader.
Christensen said that controlled deer hunting by archers – something the Medfield Lyme Disease Study Committee may recommend to the Board of Selectmen – has proven to decrease the deer population in other Massachusetts communities.
“As a town, it really comes down to being proactive, public education, working with neighboring towns…It is complicated but it has been done,” said Christensen, noting that Dover just held its first controlled deer hunt which Dover Board of Health Chairman Barbara Roth-Schechter described as a success.
Other successful culls have taken place in Acton, Andover, Boxborough, Braintree, Brewster, Concord, Duxbury, Lincoln, Marshfield, Stow, Sudbury, and Wilbraham.
Ipswich reduced its deer population from 160 deer per square mile to 27 with controlled hunts.
“The point is that this is an issue in a lot of places,” said Christensen, adding her agency is available as a free resource so the town does not have to ‘recreate the wheel.’
She made several suggestions when holding the first hunt such as using archers only, having an application or permit process for participating hunters, requiring a certain number of years’ experience, having a mandatory sign in, posting safety zone signs, and specify certain access points to hunted properties.
According to state law, hunting is not allowed on Sunday.
Christensen said there are an estimated 85,000 to 95,000 deer in the Commonwealth. She said suburban deer have been a problem for the last 20 years and continue to be a problem.
“The most growth has occurred in Eastern Massachusetts,” said Christensen, noting that Medfield is in Massachusetts’ Zone 10 (which stretches up to Boston and along the North Shore) and is considered an ‘endemic’ area. “We are looking at a goal of 6 to 10 deer per square mile…Zone 10 has around 25 or 30 deer per square mile.”
In addition to public health concerns, the overabundance of deer has ecological impacts, explained Christensen, such as a reduction in plant diversity, an increase in invasive plants, a decrease in forest regeneration, a reduced understory which then affects forest birds – the impacts are far-reaching.
Deer also pose a public safety concern.
“We have thousands of deer killed each year just by getting hit by cars,” said Christensen, noting the number is likely higher since not all incidents are reported. “State Farm Insurance predicts 7,000 deer die on the road in Massachusetts each year.”
Christensen said there is no “silver bullet” that will reduce the number of deer or Lyme disease incidents in Medfield (partially due to land access challenges, and town bylaws that may need to be revised), but said that homeowners could help by keeping their grass low, trying not to attract mice and rodents and small mammals (calling stone walls “mouse hotels”), and limiting the use of hosta and arborvitae (deer favorites) in the yard.She also noted that deer can jump anything lower than an eight-foot fence.
The Medfield Lyme Disease Study Committee said the next step is to get approval from the Board of Selectmen to hold a controlled hunt.
“If given the go-ahead, we will listen to what Dover has done, we need to learn what our current laws are, and what different federal, state and local controls are in affect…We also have a lot of large landowners and we need to clarify exactly what the rules are on their land,” said Kaldy.
The Lyme Disease Study was appointed in July 2010 by the Board of Selectmen. Its charge is to learn the best way to reduce the incidents of Lyme disease and to make a recommendation to the Board of Selectmen. They have had three meetings to date and continue to welcome public input into the process. For more information, contact the selectmen’s office at (508) 359-8505 ext 641.