Scientists present theories on deer decline at Prince of Wales Island Deer Summit

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Participants of the three-day Unit II Deer Summit walk around the Harris River to see thinning techniques on October 15. (KRBD photo by Raegan Miller).

On Prince of Wales Island, an important food source is disappearing. For years, Sitka’s black-tailed deer populations have plummeted, leaving residents without a basic protein source. A three-day summit held in Craig last month sparked lengthy discussions of the issue. Scientists have a few theories about why deer populations are declining.

On a Saturday afternoon, about 30 biologists, residents and local leaders marched along the Harris River Loop Trail, about 20 miles east of Craig, the largest town on the Prince’s Island of Wales.

A sign on the Harris River Trail (KRBD photo by Raegan Miller).

The 2022 Unit II Deer Summit was a three-day event that filled Craig Tribal Hall with representatives from wildlife agencies and conservation groups, as well as interested locals who wanted to share their opinions.

The summit was organized by a steering committee made up of Alaska residents like Dennis Nickerson from the Prince of Wales Tribal Conservation District, Ross Dorendorf and Tessa Hasbrouck from the Alaska Department of Fish and Game, and representatives from the Natural Resources Conservation Service, l University of Alaska Fairbanks and the Southeast Alaska Conservation Council. It took more than two years of preparation and officially started on October 13 and ended on October 15.

Attendees mingle during the summit at Craig Tribal Hall. (KRBD photo by Raegan Miller).

The Harris River Walk crowned the summit. It was aimed at understanding the theories presented as to why the island’s deer population is plummeting, such as poor habitat management and the legacy of clearcutting.

When loggers cut down a section of Sitka spruce, hemlock, and old-growth cedar in the Tongass National Forest, there’s no need to replant—the trees regrow on their own.

And while that sounds like a good thing, it can wreak havoc on the food web.

me Part of the Harris River Trail on October 15th. Some stands of trees on the trail were thinned using various methods, while others were left untouched. (KRBD photo by Raegan Miller).

US Forest Service Wildlife Technician Ray Slayton stopped to admire the view. He pointed to a group of trees huddled together. It’s all natural regeneration from a clearcut in 1960. He showed the forest floor, carpeted with dead leaves, twigs, moss and dirt.

“What you see is there’s no deer forage at all,” he said.

This is what scientists call an “even-aged forest”. When the trees all start growing at once, they create a dense canopy that blocks light from reaching the ferns and berry bushes that black-tailed deer love to munch on. And because the trees grow close together, they end up being long and spindly – ​​not the massive, thick, tight-grained trunks that make old wood so popular.

A great way to solve the problem is to cut down immature trees to open up the canopy. This is called thinning.

Mike Sheets of the US Forest Service explained on the walk that half of the trail has been cleared up in various ways. Some stands were pruned in a herringbone pattern, while others were thinned up or down. This was all done to try to encourage more foraging opportunities and open travel corridors for deer.

Habitat loss is one of the main theories as to why deer disappeared from the island.

The Deer Summit 2022 goals are displayed at Craig Tribal Hall on the first day of the summit. (KRBD photo by Raegan Miller).

Back at Craig Tribal Hall, Alaska Department of Fish and Game biologist John Schoen told summit attendees that old-growth forests are key habitat for deer. He says old-growth forests prevent too much snow from accumulating on the ground and provide plenty of food under the trees.

But second growth is a different story – without management there is little to feed the deer.

Jim Baichtal is the regional coordinator for the Mule Deer Foundation. He said forest managers must prioritize habitat restoration.

“What we need most now is a commitment to large-scale, radical restoration…that focuses on fixing the right places,” he said.

He said strict management of young growth is essential. He said managers should use radar to determine where trees need to be thinned. And he said the Forest Service should figure out how to make thinning an attractive business proposition for loggers.

“We need to write prescriptions for seedlings in the stem exclusion phase that will remain wind resistant and create meaningful and accessible forage in the near future. We must develop these prescriptions knowing that multiple inputs may be needed over time to continue creating fodder. We must have a market for the logs produced by these prescriptions and plan for the use of the biomass created to enable access across stands,” read a slide from Baichtal’s presentation at the summit.

But habitat loss isn’t the only theory. A number of factors are thought to be at play, including predator management.

As one participant put it, “…wolves and weather and habitat and hunting, that sums up a lot of things.”

Ecology professor Sophie Gilbert presented data showing that this could be due to the aggressiveness of black bears feeding on fawns. In one study, Gilbert said his research shows that black bears will kill 50% of fawns in their first two weeks of life. Gilbert says hinds are known to drive twin fawns away from each other, so if one is eaten, the other still has a chance of survival.

“The black bear dominates neonatal mortality,” Gilbert said.

A slide from Sophie Gilbert’s presentation. (Courtesy of Jess Forster and Mandy Park).

Gilbert also said harsh winters — known as killer winters — can quickly wipe out a deer population. She said there had not been a deadly winter since 1976. But some participants feared climate change could cause problems.

“So basically if there’s no snow everyone can usually go in the fall or spring, but if there’s snow a bunch of fawns are going to die,” said Gilbert said.

(Courtesy of Jess Forster and Mandy Park).

One of the most popular theories among residents of Prince of Wales Island is that wolves are behind the decline in deer numbers.

Craig Mayor Tim O’Connor said the wolves needed to be thinned out. State wildlife officials estimate that between 100 and 200 wolves live on the island. But O’Connor said it was a substantial undercount – he said based on what local hunters are reporting the true number is around 700 or 800.

Ross Dorendorf is the area biologist for the State Department of Fish and Game. He explained that wolves on Prince of Wales Island feed mainly on deer – that’s more than half of their diet.

Alaska Department of Fish and Game Area Biologist Ross Dorendorf gives a presentation and answers questions during the summit. (KRBD photo by Raegan Miller).

He said deer may be a safer option for a hungry wolf than taking a goat or moose.

There are different challenges for a wolf, chasing these creatures,” Dorendorf explained. “A moose is much bigger and requires certain skills so that you don’t get killed yourself when you try to eat that animal. They can trample you, they are quite dangerous. And then other challenges for (hunting) a mountain goat could be very steep terrain and chasing after it, (the wolf) falls off a cliff. It’s not very good.

A graphic from Ross Dorendorf’s presentation showing the breakdown of a wolf’s diet. (Courtesy of Jess Forster and Mandy Park).

But he said there was more to study to understand the role wolves are playing in deer population decline.

The meeting was not supposed to end with a plan to solve the problem. The organizers presented it as a place to express their concerns and opinions and learn more about the issue. Some participants suggested reducing logging of old-growth forests. Others have suggested thinning out predators and reducing deer bag limits.

But one thing is clear: there are no easy answers.

Raegan Miller is a member of the Report for America body for KRBD. Your donation to match our RFA grant helps him keep writing stories like this. Please consider making a tax-deductible contribution at KRBD.org/donate.

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