Homer Alaska - News

Story last updated at 5:58 PM on Wednesday, April 18, 2012

New research aims at getting to know moose on peninsula



By Michael Armstrong
Staff Writer


 

Photo by Thomas McDonough, Alaska Department of Fish and Game

John Crouse of the Alaska Department of Fish and Game Moose Research Center studies a radio collared cow moose last February near the Anchor River.

From the cow moose's perspective, an Alaska Department of Fish and Game research program this February might have been something out of the Alces alces X Files.

First, beings in a hovering aircraft shot a dart and stunned the moose. Next, bipedal creatures took measurements and blood samples. Then, they put a bright orange collar around the cow moose, with a radio transmitter to track her movements. Finally — there's no delicate way to put this — they implanted a device in the cow's birth canal.

That device, called a VIT, for vaginal implant transmitter, will pop out when the cow gives birth in May. Temperature sensitive, the VIT, also with a radio transmitter, will give off a signal when it goes from the warmth of the cow's body to the cold of a crisp Alaska spring, letting biologists know when the calf or calves are born.

"By knowing that exact date of birth, we'll be able to monitor that newborn calf from the day it's born to assess its survival," said Thomas McDonough, formerly the assistant area biologist for the Homer office of Fish and Game and recently promoted to research biologist for Region 2, which includes the Kenai Peninsula.

Principal investigator for the research study, McDonough is leading one of the largest studies on the peninsula of Alces alces, the scientific name for moose. In February, biologists flown in helicopters from Pollux Aviation darted and collared 50 adult cow moose each in game management units 15A on the upper Kenai Peninsula and in 15C on the lower Kenai Peninsula — 100 total.

In the field captures, biologists

• Took body measurements, including rump-fat measurements;

• Took blood draws to determine if the cow is pregnant

• Radio collared the moose to track them across the Kenai, and

• Implanted VITs to track when calves are born.

"It's pretty exciting getting all this research," McDonough said. "We now have 100 moose with all these measurements and radio collars. This is by far the biggest radio collaring on the Kenai Peninsula."

The research is partly driven by a Fish and Game intensive management program approved this year by the Board of Game, said Tony Kavalok, assistant director of of the Division of Wildlife Conservation, Alaska Department of Fish and Game. That plan included predator control, and authorized aerial shooting of wolves on state land in areas 15A and 15C.

No aerial shooting was done this winter, Kavalok said.

"Usually once intensive management programs are proposed, then the department is obligated to collect more information," he said.

The research study will answer some questions raised by the predator control plan, including how big an effect wolves and bears have on newborn moose calves. When the VIT pops out, signaling the birth of moose calves, biologists can track the cow moose and her family. Some calves will get expandable radio collars.

Biologists also can track the mother moose. If a moose doesn't move for a set period of time, suggesting the moose or calf has been killed, scientists can then go to the kill site and determine how the moose died. Like a detective at a crime scene, they can try to determine if a wolf or bear killed it. That will answer a question raised by predator control: Which species kills the most moose?

"We may find that bears are a significant factor in the survival of calves," Kavalok said.

The rump fat studies also will determine how well the habitat is doing in supporting a moose population. Some moose will be recaptured in the fall, when moose are at their peak health and fattest. By comparing winter and fall fat, biologists can assess the health of moose browse.

February's studies showed that while heavy winter snows stressed cow moose, in area 15C, the lower peninsula, cows did OK, McDonough said.

"This was an unusual snow year with relatively deep snow conditions. That obviously was something that negatively impacts the condition of the moose," he said. "The moose in 15C were in relatively good condition for how deep the snow was."

Moose in 15A, however, were in worse condition as far as body fat goes. While low, though, moose weren't starving, at least for cows. Male moose tend to have lower survival rates because they have less body fat.

"These moose are very tough animals," McDonough said. "They've adapted to the conditions during winter when their food sources are not plentiful and poor quality."

The study also will examine another question: the cow-bull ratio and the effective pregnancy rate of cows — that is, are there enough bulls to do breeding? While generally healthy, the lower peninsula moose population has had low cow-bull ratios. By looking at when calves are born, scientists can figure out when cows were impregnated. Cows go into estrus — the time when they are available to mate – in early October. If they're not bred, indicating a shortage of bulls, they go into estrus again three weeks later. By looking at when calves are born and how many are born after a later estrus cycle, biologists can get a handle on the cow-bull ratio, McDonough said.

All of this will give scientists and Fish and Game officials better tools to manage moose populations.

"Over time we've done some minimal monitoring of moose," McDonough said. "There have been some changes in habitat and changes in the level of hunting pressure. This research is really going to help as we continue to move forward with moose management."

Kavalok acknowledged that predator control and intensive management has been volatile and controversial.

"All this discussion has brought the whole issue to a crescendo," he said. "For once the Kenai is getting the attention it deserves relative to the moose population. The bottom line is we've brought the issue to the front of the table and are talking about it."

Hunters with cow hunt permits will not be prohibited from shooting radio collared moose that don't have calves, McDonough said. Information on the research program will be sent out to permit holders.

"If they could pass up on a collared animal, it would be appreciated," he said. "We're going to gain a lot of information from that animal if it stays alive."

Michael Armstrong can be reached at michael.armstrong@homernews.com.

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