With the imminent release of the latest “Twilight” vampire flick, “Breaking Dawn — Part 1,” comes another bloodsucking saga, this one in the Maine woods.

Winter tick “cluster bombs” in the tens of thousands have ambushed moose this month and last. The arachnids are taking their first blood meal and settling in for the winter.

Maine wildlife biologists Chuck Hulsey and Lee Kantar are hoping for a long, cold winter with snow lingering on the ground through April.

“Winter ticks are affected by what the previous winter was,” Hulsey said Friday. “If you have a lot of snow and a lot of cold, that’s not good for the ticks. If you have less snow and more warmth, it’s really good for the ticks.”

That’s what happened this past winter, and it’s why the biologists have heard many reports this spring of people finding more moose carcasses than usual in the woods.

That’s not to say that winter tick infestations were the culprit, because moose are also affected by brainworm and lungworm parasites that can eventually kill them.

“The winter tick itself is a huge contributor to a calf or an adult dying, but it’s not the sole cause,” said Kantar, Maine’s moose and deer biologist.

“But it’s a pretty big factor in certain years,” he said. “It may not necessarily be bad every year, but in some years, it can be higher-than-normal mortality.”

In October and November, winter tick larvae climb shrubs and grasses, gather in huge clusters and wait to ambush moose as they walk past, Kantar said.

“When the ticks are on that bush and they sense the heat of the moose walking by, they basically grab a hold and the whole cluster of moose tick gets onto the moose,” he said.

Because moose can’t groom themselves as well as deer, the ticks get a free ride unless moose manage to scrape them off by rubbing against trees. But that breaks the ungulates’ thick, protective hair, leaving them vulnerable to death from exposure.

Kantar said the ticks crawl onto moose backs, take blood meals, moult into nymphs, spend the winter, and then moult into adults with another blood meal.

In March and April, they breed and take a third blood meal before dropping off, engorged females first, each to lay a thousand eggs or so in the leaf litter before dying.

“They get literally tens of thousands of moose ticks on the back of a moose and within a two-week period of time, they’re taking so much blood that for a smaller moose like a calf, that moose can’t replace its blood fast enough,” Kantar said.

“So now you have a calf moose trying to get through its first winter, which is rough because obviously it’s not adult size. It doesn’t have the fat that adult moose have.

“In deep snow conditions, that’s tough energetically, and now in March and April, it’s got these damn ticks taking a big blood meal,” he said.

He said Maine had a mild winter in 2009-10, which set up the winter of 2010-11 for a lot of ticks.

That matters because high tick loads on moose can skew population estimates when managing moose numbers for hunting and tourism.

“That’s the million-dollar question,” Kantar said. “Which is, how does that affect the population growth or decline in the management district? I think it is a big mystery out there and other departments are very aware of this and concerned.”

Earlier this year, Hulsey said a few people who are in the woods all the time told him they found 8 or 10 dead moose, which was more than they’d ever found.

“We certainly had more reports this year than any other year, more than I’ve ever received, but you don’t know if it’s winter tick,” Hulsey said. “We do think there were more moose killed by winter ticks this year than last.” But they would have to find the carcasses before scavengers get them to know for sure, he said.

That’s why the Maine Department of Inland Fisheries and Wildlife conducts tick surveys on moose brought to tagging stations by hunters.

They’re trying to build a database on what is light, moderate and heavy for tick loads. Hulsey said moose he looked at this fall in Eustis had fewer ticks on them than he recalls seeing in the past.

Kantar said he’s worked the past two winters with University of Maine diagnostic lab techs doing necropsies on moose carcasses to determine how they died.

This year two students are specifically looking at lungworm infestations and the Department of Inland Fisheries and Wildlife will again do aerial surveys by helicopter to count moose.

“We’re doing all we can with our limited resources,” Kantar said. “It’s something that we watch extremely carefully.”

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