In this two-part series, Bjorn Dihle examines how restoration work of young growth forest by the Forest Service in collaboration with nonprofits, Tribes, and state and private partners will help Southeast Alaska’s Sitka blacktail deer population in the Tongass National Forest

My brother and I were hiking up a ridge in Southeast Alaska when we spotted a group of six Sitka blacktail bucks. There was no practical way to get within rifle range, so we spent the next few hours tunneling through the jungle and climbing cliffs until we were in good shooting position.

A short while later, the sun set on an expanse of mountains and ocean as I butchered a big, fat buck. Occasionally, I’d stand, look around, and listen for brown bears. There are a lot where we hunt, which makes for occasional excitement. It was completely dark by the time my brother and I had our deer quartered and buried in a snow slope. 

That night, I sliced and then boiled my deer’s heart for dinner. I added a handful of the plant “deer heart,” which tastes like arugula. The buck had been eating the plant when I pulled the trigger. I enjoyed my meal beneath a still, starry night and thought back to three decades ago when I was a kid making my first Sitka blacktail hunts. Not long after I killed my first buck, I had the realization that I’d rather chase these deer than do pretty much anything else.

I still feel that way.

I’m far from alone in my appreciation of Sitka blacktails. This rainforest mule deer subspecies may not be well known outside of Alaska, but for locals, as well as visiting hunters, they are a treasure. In 30 or so communities that make up Southeast Alaska, one of the most appreciated gifts you can offer someone is venison. This generosity is usually followed by the receiver of the gift telling you that there’s no better meat in the world.

Trouble in Paradise

Southeast Alaska can feel like a Shangri-la for hunters and anglers. With fishing for salmon and other saltwater species, and big game populations that still support over-the-counter tags for non-residents, it may appear there is plenty of wildlife to go around. However, the region faces some serious issues.

On Prince of Wales Island, the deer population has dropped significantly during the last few decades. The population is predicted to continue on a negative trend unless something changes. If a big winter mortality event occurs, POW’s deer may not recover. To the north, on the central islands, deer numbers are not near what they once were.

Deer populations are influenced dramatically by winter weather, and some of the recent die-offs have been near apocalyptic. Diminished old growth wintering habitat and lack of forest connectivity contributes to deer declines. In the past, logging efforts in Southeast Alaska were rarely done with wildlife in mind. Much of the best winter habitat for deer, the large old growth that protect animals from deep snows, has been clear-cut. Combine a bad winter with a lack of winter habitat and predation by wolves and bears and you end up with a recipe for an extreme deer disaster.

The Alaska Department of Fish and Game writes that, “Clearcut logging has and will continue to further reduce deer carrying capacity in some areas. Of more concern (than severe winters), habitat capability and deer numbers are expected to decline in some areas as large tracts of previously logged areas reach the closed canopy stem exclusion stage and become extremely poor deer habitat.”

Stem exclusion is when young growth forests have grown so close together they blot out the sun, creating a closed canopy where there is no understory for Sitka blacktails to browse. If these trees aren’t thinned, a Southeast Alaska forest stand in the stem exclusion phase may languish in this unproductive state for several decades to a century.

Searching for a Solution

In parts of Southeast Alaska, trappers have tried hard for decades to take enough wolves so deer populations can rebound. In some areas, their efforts have been successful on a short-term scale. Wolves are prolific breeders, though, and even with significant trapping effort, deer numbers remain poor in the central islands and are declining on POW. Studies have shown that those regions’ ample populations of black bears also prey on blacktails as they take a significant percentage of fawns. Despite the number of predators harvested, there still won’t be good numbers of deer unless there’s quality habitat.

“Fifteen to thirty years after a forest has been harvested is the best time to get in and do thinning for wildlife,” said Gregory Dunn. “We have about 200,000 acres in that framework. In ten years, we’ll be out of that window. Not much else you can do then but pre-commercial and gap treatments. The time is now.” 

One long-term solution is wildlife thinning (wildlife treatments) of young growth forests that have entered stem exclusion. This is done by thinning trees and treating slash (trees cut and left on the ground) in a particular way to allow sunlight in and the understory to grow. This in turn offers better forage for deer and better wildlife habitat overall. Thinning has occurred throughout Southeast Alaska, but until recently, it has only been pre-commercial thinning—called pre-commercial treatments. Pre-commercial treatments are done in a way that helps grow trees to be harvested but does little for wildlife. Slash, which can be stacked 10 feet high, is left on the ground. Deer can’t travel through slash, creating habitat connectivity issues and what are essentially “islands of deer.”   

Forest Service Tongass Wildlife Program Manager Gregory Dunn points out that nothing can grow for deer to browse once young growth enters stem exclusion and how it’s pressing that we do something about it now.

“Fifteen to thirty years after a forest has been harvested is the best time to get in and do thinning for wildlife,” said Dunn. “We have about 200,000 acres in that framework. In ten years, we’ll be out of that window. Not much else you can do then but pre-commercial and gap treatments. The time is now.” 

Wildlife Treatments

There are around 1,000-2,000 trees an acre in stands of young growth being considered for thinning. In the past, a silviculturist decided where crews would do pre-commercial treatments. Dunn says that now, with the new emphasis on co-stewardship of the forest, locals, Tribes, and state and private partners are involved with choosing which young growth stands will be treated. Wildlife treatments are different than pre-commercial treatments in that a crew goes into a stand with a goal of trying to trigger understory growth as well as enhance travel corridors and habitat in other ways. Dunn says the policy is that if trees have an average greater than a five-to-six-inch diameter, then the crew takes the slash out. If the average diameter is less, then the slash is left on the ground.

“You can’t get all the slash out,” said Dunn. “Wildlife treatments take more time and cost more than pre-commercial treatments. Afterwards, the understory comes back pretty fast, but it generally takes a decade or so for deer habitat to come back if slash was left at the site.”

The Forest Service is working with nonprofits, Tribes, and communities on wildlife and watershed restoration projects in different locations in Southeast Alaska. While wildlife treatments take time, Dunn and others hope that thinning and timber harvest is done in a way to enhance or maintain quality habitat for wildlife in the future.

“It’s a huge issue to keep deer from disappearing, as deer are vital for residents of Southeast Alaska,” said Dunn.

Knowing how much people care about Sitka blacktails, it’s a safe guess that hunters will do everything they can to keep that from happening.

Bjorn Dihle is an avid hunter, conservationist and lifelong resident of Southeast Alaska.

Look for Part II of this series on Sitka blacktail conservation in Southeast Alaska soon.

Photos courtesy of Bjorn Dihle.

TRCP works to maintain and strengthen the future of hunting and fishing by uniting and amplifying our partners’ voices in conserving and restoring wildlife populations and their habitat as challenges continue to evolve.   Learn more about TRCP’s commitment to healthy habitat and clean water HERE.