Winter ticks are killing moose at a truly alarming rate

Ghost moose
© Dan Bergeron / N.H. Fish and Game Dept.

This is what climate change looks like.

The photo above is of a “ghost moose.” The poor thing has lost much of its coat due to a high load of winter ticks, which have increased in unusual frequency in northern New England.

Researchers at the University of New Hampshire say that the increase in winter ticks is linked to climate change in the form of longer autumns with later snow.

And it's proving to be devastating to moose populations in places like northern New Hampshire and western Maine. The ticks are so plentiful and voracious that they are sucking the life right out of these majestic members of the deer family.

In a new report, the researchers found that the increase of tick infestations is the primary cause of an unprecedented 70 percent death rate of calves over a three-year period. The ticks attach themselves to moose during the fall – during "questing" season – and feed throughout the winter.

"The iconic moose is rapidly becoming the new poster child for climate change in parts of the Northeast," says Pete Pekins, professor of wildlife ecology at the University. "Normally anything over a 50 percent death rate would concern us, but at 70 percent, we are looking at a real problem in the moose population."

The scientists tracked 179 radio-marked moose calves for physical condition and parasites in the month of January over three years from 2014 to 2016. They found that 125 calves died during the period – with each calf hosting an average of of 47,371 ticks per moose. Emaciation and severe metabolic imbalance from blood loss were the primary causes of death.

"Most adult moose survived but were still severely compromised," notes the University. "They were thin and anemic from losing so much blood. The ticks appear to be harming reproductive health so there is also less breeding."

While winter tick epidemics usually last a year or two, five of the last 10 years has shown a rare frequency of tick infestations which reflects the influence of climate change, explain the researchers.

"We're sitting on a powder keg," says Pekins. "The changing environmental conditions associated with climate change are increasing and are favorable for winter ticks, specifically later-starting winters that lengthen the autumnal questing period for ticks."

Forget about a death by a thousand cuts, this is death by tens of thousands of ticks, what a miserable fate. Welcome to climate change.

The study was published in the Canadian Journal of Zoology.

Winter ticks are killing moose at a truly alarming rate
This is what climate change looks like.

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