Biologist measures low body fat in valley moose
April 4, 2019
“We don’t know a lot about moose around Haines,” said Carl Koch, a wildlife biologist for Alaska Department of Fish and Game. “We know a lot about Gustavus and we know a lot about Berners Bay, but not a lot about the Chilkat Valley.” This year’s survey occurred in the last week of March, and its goal, said Koch, was to learn about the valley’s moose population.
“It went very well actually,” he said. Koch’s team tagged 24 female moose from “Murphy’s flat all the way up to upper Chilkat,” he said. In the past, gathering moose data has been hard around Haines. Koch has to survey the moose in “good snow,” when they stick out, and before their antlers drop around November to accurately identify moose genders. Otherwise, “we can only accurately identify cows with calves,” he said.
In order to tag a moose, a spotter plane first finds it, and then a biologist and a pilot go ahead of the animal and dart it from afar. Once the moose is “chemically immobilized” they are able to handle it.
He said that the use of a spotter plane this year turned out to be essential because, without much snow, the moose were more difficult to discern. When moose biologist Kevin White measured the animals’ body fat with an ultrasound, he was surprised by the low amount of fat on the moose in the valley in spite of early spring conditions—it was what he might have expected to see during a very severe winter.
“It would be interesting to see what’s going on with the system in the Chilkat Valley that may be affecting that,” said Koch.
Deep snow makes it harder for moose; they have to expend more energy and it is harder for them to access food, said Koch. In the Chilkat Valley, where snowfall was less this year, Koch looked to the moose’s sources of food. Most of their winter food is willow, cottonwood and red dogwood, he said, and the diameters of these stems were pretty thick, indicating that there may be more competition.
Koch also found that “there was an awful lot out there that was not edible.”
In late May and June, Koch’s team will count how many of the calves have survived.
“We’re going to learn a lot more than we did in the past, most importantly about accurate populations, how the population changes,” he said. “It will be interesting to see how similar adults and calves are,” said Koch.
Moose calves are born at the end of May, into June. “Before they are grown enough to run fast, the strategy is for the cow to stash them,” said Koch. “The cow is often not that far away, but sometimes when dogs are around and things like that they’ll separate.”
If anyone in Haines sees one of the collarded moose, Koch asks that they call Fish and Game with the following information: when and where they saw the moose, the collar color, the collar number and if the animal had calves with it.