How hunting moose could save the moose population

STEVE INSKEEP, HOST:

In Northern New England, shorter winters with less snow are creating a problem for moose. Native winter ticks are thriving on moose. Some states have been trying to help the moose by hunting them. Vermont Public Radio's Abagael Giles explains.

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ABAGAEL GILES: It's a glorious day in a remote part of the rugged Northeast Kingdom, sunny and cold. Nick Fortin is Vermont Fish and Wildlife's lead moose biologist. He says the new growth from logging at this spot makes for prime moose habitat.

NICK FORTIN: Sort of a high-elevation basin between two mountains. And it's mostly dominated by spruce and fir.

GILES: After a long snowmobile ride, Fortin and his colleagues are here to set up game cameras.

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GILES: The idea - to build a population model that will help biologists track the health of New England's moose population in real time because in recent decades, the relationship between moose and one of their parasites, winter tick, has changed.

FORTIN: This year's a perfect example. We're out here in the end of February, and there's maybe a foot of snow. And we're at 2,500 feet of elevation. I mean, we should have 4 to 5 feet of snow on the ground right now.

GILES: The problem is swarms of winter ticks seek out a host just before first snow.

FORTIN: We'll often call them tick bombs.

GILES: When snow comes late, they have more time to find a host. And unlike white-tailed deer, moose are poor groomers. So a single animal can carry as many as 90,000 ticks through the winter. Then in the spring, the ticks drop off to reproduce. So the more moose in an area, the more ticks. Since moose like to eat the yummy new growth in areas like this, it means denser-than-normal moose populations.

FORTIN: And, yeah, we got used to that. But that's not something that is probably sustainable in the face of winter ticks and climate change.

GILES: Right now only about half of moose calves survive their first winter in this basin. Biologists say reducing the density of moose here by about half would help.

FORTIN: And that's a tough sell to a lot of people.

GILES: People like Brenna Galdenzi with the advocacy group Protect Our Wildlife Vermont.

BRENNA GALDENZI: Is there any way to prove to Vermonters, you know, in three years or four years or five years that, you know, the deer or the moose herd is now healthier and that's due to the moose hunt?

GILES: Cheryl Frank Sullivan is an entomologist at the University of Vermont. She's been looking into another option - kill the ticks using pesticides made of fungi found naturally in New England soils. Spoiler - more research is needed. But in the meantime, Frank Sullivan says reducing the density of moose hosts on the landscape - moose social distancing, if you will - may just be the best option available.

CHERYL FRANK SULLIVAN: It's - weather conditions, host density and the overlap of that seasonal habitat use by moose are really the main factors that drive the winter tick abundance on the landscape.

GILES: After several years with very little or no hunting, Vermont issued 100 moose permits last year. Fish and Wildlife is recommending the same this year just for Essex County, where the moose are most dense. One state away, Maine is in the second year of a similar experiment. Lee Kantar, Maine's moose biologist, says he knows killing moose to save them is counterintuitive. But the state now sees about two weeks less winter than it did a century ago, and those two weeks are the difference between life and death for calves.

LEE KANTAR: All we're living with is the winter tick-moose-climate dynamic, and this is our way of trying to do something now and not ponder it for another five years.

GILES: Kantar and his colleagues in Vermont hope they can give moose a chance to adapt to whatever a changing climate holds.

For NPR News, I'm Abagael Giles in East Haven, Vt. Transcript provided by NPR, Copyright NPR.