Heed lessons from 1960s island wolves
NED ROZELL - ALASKA SCIENCE
The killing of wolves to boost moose and caribou populations in Alaska has made headlines all over the country. Back in 1960, a government program to stock an Alaska island with wolves received less attention.
Alaska had been a state for one year when its Department of Fish and Game conducted a wolf-planting experiment on Coronation Island in Southeast. The remote 45-square-mile island exposed to the open Pacific had a high density of black-tailed deer and no wolves. In 1960, biologists from Fish and Game released two pairs of wolves on the island.
The experiment was the only wolf-stocking effort undertaken in Alaska and probably the whole world at that time, said Dave Klein, a professor emeritus with the University of Alaska's Institute of Arctic Biology. Klein, who had studied deer on the island, helped the state make the decision to introduce wolves there:
"Alaska had just become a state and you had a brand new Department of Fish and Game staffed with young biologists who wanted to do things based on biology rather than a mix of politics and science. It'd be much more difficult to do it now."
In 1960, Fish and Game biologists released the two male and two female wolves at Egg Harbor on Coronation. Before they left, they shot five deer to provide food for the wolves.
Biologist Paul Garceau visited the island in May 1961 and found tracks, deer remains and wolf scats containing deer hair and bones, showing that the wolves had adapted to life on the island. Two months later, a commercial fisherman shot the two adult female wolves, but Garceau saw tracks of wolf pups on the island when he returned later that summer. The females had given birth before they died and the pups had survived.
In 1964, Fish and Game biologist Harry Merriam explored for eight days and saw 11 adult wolves and the tracks of two pups. He estimated that at least 13 wolves lived on the island and three litters of young had been born since the first wolves arrived.
The next summer, Merriam spent 10 days there, seeing wolf tracks on all beaches. He saw no sign of deer on the north side of the island but found deer tracks on the steep slopes of the south side, where rough terrain and dense brush may have provided the best chance to escape wolves.
In February 1966, Merriam saw only three wolves on the island, and their tracks suggested they were the only ones left. He examined more than 100 wolf scats; six of those contained wolf remains only, suggesting the animals had resorted to cannibalism. Deer remains in the scats were less than one-half of the previous spring; fragments of birds, seals, sea creatures and small mammals constituted the rest.
In August that year, Merriam and his partners collected seven wolf scats, compared to 201 a year before. They found just three sets of fresh deer tracks. By 1968, one wolf remained on the island. Biologists who inventoried the island's animals in 1983 found no evidence of wolves, but the deer were once again plentiful.
Alaska's only wolf-stocking experiment taught biologists the importance of habitat size. They concluded that a 45-square-mile island was too small for both deer and wolves. The study also showed that a lot of factors play into the dynamics of a wild animal population, which is a point Klein said many people miss in current arguments about wolf control.
"The relationship between wolves and their prey is very complex," he said. "Sometimes wolves are the key predators of caribou or moose, sometimes bears. Sometimes severe weather is the main factor, sometimes food availability.
"The main problem with these kinds of controversies is people are unwilling to look at the complexity of the ecosystems involved. Things are not simple in nature."
Anchorage Daily News
The killing of wolves to boost moose and caribou populations in Alaska has made headlines all over the country. Back in 1960, a government program to stock an Alaska island with wolves received less attention.
Alaska had been a state for one year when its Department of Fish and Game conducted a wolf-planting experiment on Coronation Island in Southeast. The remote 45-square-mile island exposed to the open Pacific had a high density of black-tailed deer and no wolves. In 1960, biologists from Fish and Game released two pairs of wolves on the island.
The experiment was the only wolf-stocking effort undertaken in Alaska and probably the whole world at that time, said Dave Klein, a professor emeritus with the University of Alaska's Institute of Arctic Biology. Klein, who had studied deer on the island, helped the state make the decision to introduce wolves there:
"Alaska had just become a state and you had a brand new Department of Fish and Game staffed with young biologists who wanted to do things based on biology rather than a mix of politics and science. It'd be much more difficult to do it now."
In 1960, Fish and Game biologists released the two male and two female wolves at Egg Harbor on Coronation. Before they left, they shot five deer to provide food for the wolves.
Biologist Paul Garceau visited the island in May 1961 and found tracks, deer remains and wolf scats containing deer hair and bones, showing that the wolves had adapted to life on the island. Two months later, a commercial fisherman shot the two adult female wolves, but Garceau saw tracks of wolf pups on the island when he returned later that summer. The females had given birth before they died and the pups had survived.
In 1964, Fish and Game biologist Harry Merriam explored for eight days and saw 11 adult wolves and the tracks of two pups. He estimated that at least 13 wolves lived on the island and three litters of young had been born since the first wolves arrived.
The next summer, Merriam spent 10 days there, seeing wolf tracks on all beaches. He saw no sign of deer on the north side of the island but found deer tracks on the steep slopes of the south side, where rough terrain and dense brush may have provided the best chance to escape wolves.
In February 1966, Merriam saw only three wolves on the island, and their tracks suggested they were the only ones left. He examined more than 100 wolf scats; six of those contained wolf remains only, suggesting the animals had resorted to cannibalism. Deer remains in the scats were less than one-half of the previous spring; fragments of birds, seals, sea creatures and small mammals constituted the rest.
In August that year, Merriam and his partners collected seven wolf scats, compared to 201 a year before. They found just three sets of fresh deer tracks. By 1968, one wolf remained on the island. Biologists who inventoried the island's animals in 1983 found no evidence of wolves, but the deer were once again plentiful.
Alaska's only wolf-stocking experiment taught biologists the importance of habitat size. They concluded that a 45-square-mile island was too small for both deer and wolves. The study also showed that a lot of factors play into the dynamics of a wild animal population, which is a point Klein said many people miss in current arguments about wolf control.
"The relationship between wolves and their prey is very complex," he said. "Sometimes wolves are the key predators of caribou or moose, sometimes bears. Sometimes severe weather is the main factor, sometimes food availability.
"The main problem with these kinds of controversies is people are unwilling to look at the complexity of the ecosystems involved. Things are not simple in nature."
posted by wolf saga at 6:58 PM
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