Since being introduced in 1916 by the Cordova Chamber of Commerce, Prince William Sound's Sitka black-tailed deer population has usually thrived, exceptionally well at times. However, following last winter's record snowfall, biologists say the population fell to an all-time low. State managers expect to close the hunting season on Friday, about a month earlier than usual, with federal managers looking to close the subsistence season for does at the same time.
"Deer can handle the cold and wind, but snow covers their food and restricts their movements," said Dave Crowley, biologist with the Alaska Department of Fish and Game. "We estimate that following last winter the mortality rate was 50 to 70 percent -- and could be 80 percent or higher in the western Sound."
According to Crowley the last bad winter for the region's deer population was 1998-1999, with a 55 percent mortality rate.
Northern edge of range
"It takes a series of mild winters for the deer to spring back," Crowley said. "In 1998-1999 we saw a record high harvest and the following year a record low. Then there was another bad winter and the population never recovered to what it was before 1998-1999. We were getting closer, but then we had last winter."
Prince William Sound is the extreme northern edge of Sitka black-tailed deers’ range, but the population usually thrives because of mild climate conditions and the snow-shading canopies of old-growth forest that provide shelter and access to nutritious vegetation that deer love -- green bunchberry, golden thread, trailing bramble, blueberry. At one point, deer in Prince William Sound were so successful that by 1945 the population was out of control and damaging its habitat.
"There was a massive die-off because the deer had exceeded the carrying capacity of the Sound," said Crowley. "Agent Robards of the Alaska Game Commission, predecessor to ADF&G, fought to allow a doe hunt. It was controversial. Eventually, it was realized that you need a liberal season and bag limits to control the population."
More art than science
Crowley says most deer can survive brutal winters, but die in the spring while eating kelp and other foods that don't provide the nutrition they need, or foods that can't be properly broken down by their specialized digestive systems. "Hunting has little impact on the population," Crowley said. "It's winter."
The science of tracking population numbers is more art than science Crowley acknowledges. While there is a long history of deer management in the Sound, it's impossible to really know what the population is. Crowley says he suspects that prior to last winter, the region supported between 20,000-40,000 animals, but now the population may be below 20,000. Methods for gathering data include deer-pellet transects and harvest reports. Crowley says he can tell by simply looking at surrounding plant species if deer are present.
Anecdotal information from hunters is vital to Fish and Game biologists. A typical harvest objective is in the range of 2,200 to 3,000 deer, but Crowley says hunters aren't seeing a lot of deer so far this winter. "The deer are harder to find and fewer hunters go out," he said.
Fewer deer on the home range helps the animals’ forage recover, which in turn helps the deer bounce back.
"Our hope is that subsistence hunters will lay off the does," said Crowley. "With a mild winter and access to good nutrition, they will pop out twins and we will be on our way to recovery."
Jennifer Gibbins is editor of The Cordova Times. Used with permission.