Solving a moose mysteryOur group’s two-way radio was dead, but we still could tell where the downed moose was by the tight-circling Cessna spotter plane overhead.
By: John Myers, Forum Newspapers, Lake County News Chronicle
Our group’s two-way radio was dead, but we still could tell where the downed moose was by the tight-circling Cessna spotter plane overhead.
We snowmobiled in as far as we could, then waded through waist-deep snow to where the young bull lay in a logged-off patch of Superior National Forest about 40 miles north of Two Harbors.
The Colorado-based Quicksilver Air Inc. helicopter crew used a tranquilizer gun to bring the bull down, and then landed nearby. They had already finished their work when we arrived, placing collar No. 65.110 around the bull’s neck.
Blood samples were taken. Scat, hair and a few winter ticks hitching a ride were collected. Measurements were logged. Then the helicopter and crew were off looking for another moose to dart.
Meanwhile, researchers in our group checked the bull’s hind-end body fat using an ultrasound, gave him a shot of antibiotics and finally, all within about 30 minutes, an antidote to revive the bull from his unscheduled nap.
“This one looks pretty good. He’s still got a little fat remaining on that rump,’’ said Glen DelGiudice, a Minnesota Department of Natural Resources biologist.
It’s that fat that gets moose through Minnesota’s tough winters without starving to death and, for reasons not fully understood, fewer moose are making it.
Four minutes after receiving the antidote the bull was on up on its long legs and trotting off – another of more than 60 of the animals that are being collared this winter in what will become Minnesota’s largest moose study ever.
From Voyageurs National Park on the west to the Grand Portage Reservation on the east, researchers from a half-dozen agencies are trying to discover why the Northland’s moose are in decline. It’s also the first study to track moose on both sides of the international border, with several in Quetico Provincial Park now collared and monitored.
The work is done in the winter when the black and brown moose stand out against the snow in the leafless forest, and when marshes and bogs are frozen over.
After Northwestern Minnesota’s moose population crashed from 4,000 to just a few dozen over the past 25 years, Northeastern Minnesota moose now are showing similar warning signs. Fewer calves are surviving their first year, and overall moose numbers are trending down. The phenomenon is creeping north into Ontario as well.
Research papers identify higher summertime temperatures in recent decades as an underlying issue. But that’s not what’s actually killing the animals. Scientists believe it’s a combination of higher temperatures, parasites such as brain worm and ticks, disease, increased deer numbers, predation from wolves, habitat decline, nutrition and a host of other potential factors.
It may be how moose are reacting to higher temperatures that’s adding to the problem, researchers say.
Researchers want to know where moose are going to eat, rest and seek shade and cool water on warm days, and where they go to have their calves and to die. And that’s what this $1.1 million project, funded through federal, state, tribal and provincial sources, is expected to do. Researchers can even overlay what the weather was like, including the temperature, for each position recorded by the GPS.
The GPS unit on the collar will take a reading every 20 minutes for at least the next two years, and every four hours a tiny satellite phone calls a researcher’s computer at the Natural Resources Research Institute in Duluth and sends the coordinates.
Minnesota moose have been studied for years, but mostly with radio-
transmitter collars that require researchers to recapture the moose to recover the data. That requires expensive and time-consuming airplane flights to keep track of the animals. And it may be days or weeks before researchers know the animal is dead.
The new GPS/satellite phone collars ($3,500 each) offer researchers a new world of data. In a pilot project last year, collars on 21 moose in Voyageurs and Grand Portage provided tens of thousands of data-points over just a few months – exactly where each moose was every 20 minutes.
“It’s the first time we’ve been able to real-time track moose wherever they go," said Ron Moen, the coordinating researcher among a half-dozen or more who are working on the project. The goal, he noted “is to see what we can do to keep moose in Minnesota longer."
A sense of urgency
So far northeastern Minnesota’s moose population has not dropped to a crisis level. The DNR broadly estimates there are about 6,000 moose in their core survey area in Cook, Lake and northeastern St. Louis counties. But state, federal and regional researchers want to find out all they can before that number drops more.
Some moose experts have questioned whether Minnesota moose can survive higher temperatures when they are already at the southern edge of their North American range. Others are more hopeful.
“We can’t do anything about warmer temperatures, not fast enough. And we can’t do anything about disease,’’ Moen said. “But maybe there are things about habitat, about what they need to survive the warmer temperatures – things we can do in forest management that will help them hang on.’’
Next winter, if money from the state’s Environment and Natural Resources Trust Fund is approved, DelGiudice and DNR veterinarian Erika Butler hope to put GPS/satellite phone collars another 100 moose to expand the overall study to more than 160.
While Moen’s work focuses on habitat and when and why moose uses certain parts of the forest, DelGiudice and Butler will look at what’s killing the moose.
The GPS/satellite collars will allow researchers to know within about 4 hours if a moose stops moving and is likely dead, and, they hope, to get to the dead animal within 24 hours so it can be retrieved for a necropsy.
Butler said past efforts to use forensic science often have proved fruitless after researchers find radio-transmitter collars on decomposed moose.
“We know it’s not predation that’s killing them in most cases. … But we need to get in that fast or they (the dead moose) can’t tell us anything,’’ Butler said. “If we don’t do this, we’ll never know what’s killing our moose.’’