Bears take biggest bite of young moose population
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Fish and Game researchers radio-collar an adult cow moose in order to track her and her calves. In the blue jacket is John Crouse, director of the Moose Research Center. Thomas Donough is wearing an orange vest.
“It used to be that on a trip to Anchorage you would see 40 moose along the side of the road and hunters would pack their freezer with moose meat,” said Jim McCracken, chairman of the Seward Fish and Game Advisory Committee, a local citizen’s group that advises the Alaska Board of Game and Alaska Board of Fish on published proposals. Nowadays longtime area hunters like him are scratching their heads and wondering, “Where are the moose? Why are we seeing such a decline, and how do we get the curve moving the other way to where the moose start to recover?” said McCracken.
Part of an ongoing three-year study in Game Management Unit 15C confirms that bear predation was probably the main cause of death for young moose calves on the Kenai Peninsula during their first three to six weeks of life. The second highest cause of death of the young calves being studied was the research itself.
The researchers’ preliminary field study results show that 45 of the 54 newborn calves being studied subsequently died, most at the hands of grizzlies. Brown bears killed 19 (or 35 percent) of the calves they had studied. Seven of the calves (13 percent) died from abandonment. Black bears killed two calves and an undetermined bear species killed five more. Meanwhile, wolves or coyotes killed one, an unknown predator killed three, four died from unknown causes three drowned, and disease killed one.
The young moose-calf mortality study took place in Game Management Unit 15C. It was part of an ongoing look at moose trends in Game Management Unit 15A and 15C. GMU 15C is an area south of Tustumena Lake and west of the Kenai Fjords National Park. Unit 15A is on the northwestern part of the peninsula, north of Sterling and Soldotna and west of the mountains.
This three-year moose study is especially important because the Alaska Board of Game has targeted both areas for an aerial wolf control program allowed under the state’s intensive management law of 1994. Intense management can be implemented when a particular species’ population drops below certain pre-established levels or harvest objectives, said Jeff Selinger, one of the Kenai Peninsula-based researchers from the Alaska Department of Fish and Game.
Intensive management is action taken in lieu of traditional methods such as restricting hunting seasons, bag limits, open or closed seasons. It can include either the deliberate killing of known predators or a variety of forms of habitat manipulation such as controlled burns or clear cutting and scarification to provide more game to benefit hunters, said Selinger. The proposed aerial wolf-control area in 15C includes all lands north of Kachemak Bay, about 1,171 square miles of the Peninsula. This portion of land is home to an estimated 40-75 wolves. The Alaska Board of Game has proposed to kill at least 50 percent of the wolves or about 38 wolves there. Although the controversial wolf-control plan for the Kenai Peninsula has already been approved it has not yet been initiated. Overall, moose populations in 15C are not declining and population objectives are already being met, the researchers said. But because the game board restricted the bull harvest in 2011 due to a decline in the area’s bull to cow ratio, the harvest fell below intensive management harvest objectives.
The studies are attempting to gather baseline data to help guide future game management decisions and also to fill in some of the gaps pertaining to the area’s moose population changes, said Thomas McDonough, biologist with Fish and Game in Homer and the principal investigator of the moose calf study. Research will also examine the effects of last year’s record snow conditions on moose reproduction which should become evident during field studies in the next calving season, he said. Providing pertinent information to the board is crucial because some of the proposed intensive management actions are pretty high profile and call for major manipulations in the environment, said McDonough.
Initially, the researchers caught and radio-collared a group of moose cows in February then tracked their signals. Then, during their breeding season, they flew daily over areas in which the pregnant cows were located to see if they had calved yet. If they saw a young calf their mini-helicopter landed nearby and they quickly found, weighed and radio-collared the calf before returning to the helicopter. The mother cow would remain within 50 yards while researchers processed the calves. “There’s no darting involved,” said McDonough. “Typically we’re out of there within 30 seconds.”
When the calves’ radio signal indicated it had died, the researchers returned to that particular area to gather the calves’ carcass, or footprints, fur, or other evidence of how the death had probably occurred.
Their latest studies’ finding that bears caused the majority of young moose calves’ mortality was expected. It’s already been well established in similar studies throughout Alaska that about half of the young moose calves born don’t survive to adulthood and that, most frequently, they are killed by bears during their first few weeks of life, said McDonough. Later in life adult moose and their older calves tend to elude bear predation but can fall victim to wolves which are plentiful in GMUs 15C and 15A. They can also die from a variety of other causes including adverse weather conditions, loss of browsable habitat and more, he said.
It’s already well known that the highest predation on moose calves is bears, said McCracken. He’s more focused on wolf predation. McCracken points to compelling studies presented to the committee earlier by Ted Spraker, a game board member and former Fish and Game researcher from the Kenai Peninsula who advocated for the wolf control plan. Spraker pointed to the 22 documented packs of wolves on the Kenai Peninsula and that a pack of wolves makes a kill every four or five days on either a moose or caribou, said McCracken.
However, critics of the wolf control plan have pointed to the history of raging wildfires on the Kenai Peninsula and the subsequent rebounding of the moose population following each fire as mature woodland was replaced by the woody browse preferred by moose. They say the loss of habitat or other reasons, not wolves, is more to blame for a decline and suggest that altering habitat with methods such as controlled burns or clear-cutting and scarifying the soil would be preferable. Some also dispute intensive management and don’t believe that there actually is a problem that needs addressing. They reason that just because moose were once more abundant, and harvests were higher over the area, shouldn’t mean that game today should be managed based on the former numbers.
The Seward Fish and Game Advisory Committee holds its regular meeting at 7 p.m. Thursday, Nov. 1 in Seward City Council Chambers, and will hear an update from area researchers on the preliminary findings of their studies of moose on Game Management Unit 15C and 15A on the Kenai Peninsula.