Deer hunters must take precautions against Lyme disease

Dad's big buckAs we prepare for opening day of the firearms season on deer this Saturday, this warning is important. It was issued by the Maine Lyme Disease Research Laboratory in 2004, and included in the media guide, titled Why Maine Needs Hunters, issued by the Sportsman’s Alliance of Maine and Department of Inland Fisheries and Wildlife.

Warning for deer hunters

Hunters could bring the risk of Lyme disease into their own back yards.

As a deer’s body temperature drops, live deer ticks drop off, a process that may take days. The ticks, which might be infected with the bacteria that cause Lyme disease, may establish a population in their new territory.

So hunters are strongly advised to place a large tarp or a child’s swimming pool filled with water under a hanging deer. Then as the ticks fall, they can’t readily get out of the water and disperse.

That warning was included in an article titled: As concern about Lyme disease increases, hunters help keep the deer herd under control. The article is still timely, and I encourage you to share it with both hunters and nonhunters. This is a very important message, which every Mainer needs to hear.

I expect the new deer management plan, currently being developed by DIF&W and a Steering Committee of folks representing a variety of groups, will address this issue in an aggressive way in the new plan. The problem of Lyme disease – and other diseases contracted from deer ticks – has gotten much worse since this article was published.

Tomorrow I’ll tell you the story of the island of Monhegan, which killed all of its deer and eliminated Lyme disease.

The Article

Not so long ago it seemed as if many Mainers valued deer and were afraid of hunters. Now that’s being reversed.

As deer populations in southern and coastal Maine climbed to historic levels over the past two decades, people began to worry about deer problems, including vehicle collisions and damage to farms and gardens. But no single issue has raised both awareness and concern about the growing deer population as much as Lyme disease, which is transmitted by deer ticks.

“Lyme disease has really brought coastal deer populations to the forefront,” says Phil Bozenhard, the regional wildlife biologist for southern Maine. “It’s a compelling argument to institute some kind of a control program in places like Wells where we have a controlled hunt, and Georgetown where they’re going to have a controlled hunt this year. Lyme disease is a real concern.”

The connection between deer, deer ticks and Lyme disease has become well known as 918 cases were reported in Maine from 1990 through 2003. This year’s cases are likely to match the 175 reported in 2003, state officials say. (NOTE – in 2014, Lyme cases in Maine totaled 1,399).

It’s also become clear, in part because of Lyme disease research in Maine, how important it is to control the deer population and what a critical role hunters play in that process.

Yet more than 100 Maine towns restrict or ban firearms discharges in some areas. Hunting also was banned on most of Maine’s populated islands, because of fear of accidents in such close quarters. But without hunting and with mostly mild winters, deer in some areas have increased to more than 100 per square mile. A tolerable level for both people and deer is around 15 per square mile.

“In a lot of towns that have real deer tick problems, hunting is not allowed,” says Mary Holman, a researcher with the Lyme Disease Research Laboratory at the Maine Medical Center Research Institute. “So that’s a problem, because the herd is not being controlled.”

Deer play an essential role in the two-year life cycle of deer ticks, even if they don’t infect ticks with Lyme disease. White-tailed deer are the primary source of blood that female deer ticks need in order to lay as many as 3,000 eggs. Although adult deer ticks bite large mammals, including people, dogs and even horses, their preferred hosts are deer.

Many people think they’re safe from deer ticks in fall, but it’s actually the peak time to encounter adult ticks, Holman says. Since hunters usually wear boots and heavy clothing, they have more protection than outdoor enthusiasts do in spring and summer when the tiny larvae and nymphs are more active. People also are more likely to feel the bite of an adult tick and remove it before the tick has time to transmit the bacteria that cause Lyme disease.

What hunters should realize, however, is that whenever they handle or hang a deer, they may bring the risk of Lyme disease into their own back yards. As a deer’s body cools, deer ticks drop off. So Holman strongly advises hunters to put a large tarp or a child’s plastic swimming pool filled with water under the deer. Then as the ticks fall off, they can’t readily get out of the water and disperse.

“If they happen to hang a deer, for instance, on the side of their barn and the ticks fall into a perennial bed,” Holman says, “it’s possible that they could be allowing live deer ticks to establish themselves in their yards or in their homes… It can take a period of several days for the ticks to drop off of the hide, but once they realize they’re no longer feeding, they will drop off.”

For a decade, the Lyme Disease Research Laboratory has been mapping the range of the deer tick in Maine by the ticks sent for identification. In 1997, for example, 449 deer ticks were submitted. Last year, the lab received more than 1,300.

“Six or seven years ago we didn’t see very many deer ticks coming from towns like Yarmouth, Freeport, North Yarmouth, and Brunswick, but now we are,” Holman says. “The same is true around places like Deer Isle. It’s definitely becoming more common.” (NOTE the ticks have spread much further throughout the state since this article was published).

Much research is still to be done on Lyme disease and deer density. “For example, it is just not known,” says Dr. Kathleen Gensheimer, state epidemiologist, “what the level of a deer population must be in order to reduce the risk of Lyme disease.”

But it’s already clear that keeping deer populations in balance is an important part of the battle to reduce deer tick numbers. To do that, state wildlife biologists say, they must be able to remove the right number of deer from the right places.

“Hunting is the only significant management tool that we have at our disposal,” says Gene Dumont, state supervisor of regional wildlife biologists. “All of the other things that are at our disposal are short-term attempts to try to protect your property. The only long-term solution is managing deer at appropriate levels and hunting is our only tool to do that.”

PHOTO: My Dad, Ezra Smith, with one of his big bucks.

George Smith

About George Smith

George stepped down at the end of 2010 after 18 years as the executive director of the Sportsman’s Alliance of Maine to write full time. He writes a weekly editorial page column in the Kennebec Journal and Waterville Morning Sentinel, a weekly travel column in those same newspapers (with his wife Linda), monthly columns in The Maine Sportsman magazine, two outdoor news blogs (one on his website, georgesmithmaine.com, and one on the website of the Bangor Daily News), and special columns for many publications and newsletters. Islandport Press published a book of George's favorite columns, "A Life Lived Outdoors" in 2014. In 2014, George also won a Maine Press Association award for writing the state's bet sports blog. In 2016, Down East Books published George's book, Maine Sporting Camps, and Islandport Press published George and his wife Linda's travel book, Take It From ME, about their favorite Maine inns and restaurants.