Living amid craggy peaks and remnant glaciers, Southeast Alaska mountain goats survive in variable conditions, often dealing with heavy snowfall and extreme cold. But a new study published and written by an Alaska wildlife ecologist shows that many goats die in avalanches.
Kevin White, who worked with the Alaska Department of Fish and Game before continuing his studies at the University of Alaska Southeast and University of Victoria, British Columbia, has concluded over a 17-year project, using data from 421 collared goats, that between 23% and 65% of them died in avalanches, depending on conditions in a given year.
Baranof Island had the highest percentage of all deaths caused by avalanches. “It’s not just that Baranof is a place that’s extraordinarily steep and rugged … but it also gets a lot of snow. So it’s prone to avalanches,” he said.
“But the other important consideration with respect to Baranof is in the wintertime there’s really very limited chance of predation like there is on the mainland when there’s wolf packs,” White added.
He co-published the study, “Snow avalanches are a primary climate-linked driver of snow ungulate populations,” with several other researchers in the scientific publication Nature this spring.
A future line of questioning, White said, will revolve around the impact of climate change on snowpack, and how warmer conditions in Southeast impact avalanche risk and goat mortality.
Goats, with their uncanny ability to traverse vertical terrain, tend to inhabit mountaintops far above the tree line, and excel in that alpine ecosystem.
“They’re a species that just feels like they’re straight out of the last Ice Age, and they really are, actually; they still are living in Ice Age environments, like what’s remaining of remnant glaciers,” White said.
He first came to Alaska in 1996 for moose research in the Talkeetna area, but in 2001 moved to Juneau to work with Fish and Game. Since 2022, he’s been with both the University of Alaska Southeast and British Columbia’s University of Victoria, where he’s working on his dissertation. He lives in Haines.
The study delves into “a widespread but previously undescribed pathway by which snow can elicit major population-level impacts and shape demographic characteristics of slow-growing populations of mountain-adapted animals.”
He studied collared goats in Lynn Canal near Klukwan, on Baranof Island and on the Cleveland Peninsula north of Ketchikan, with the highest rate of avalanche fatality occurring on Baranof.
While predators will often target the old, young or infirm, White noted, avalanches kill indiscriminately, often taking out mature adults.
“Avalanches are taking out prime-aged animals that are the most important ones for popular population productivity,” he said. “That’s a pretty important take-home point.”
Avalanche deaths peaked in periods of unstable snow — in October and November as snowpack first accumulates, and in April and May as it melts.
Due to the nature of falling in an avalanche, the study says, this manner of death presents a “wicked problem” to goats.
“While we didn’t explicitly test whether mountain goats select specific terrain types to avoid avalanches during risky periods, the complex and dynamic physical interactions that create avalanche vulnerability are likely difficult to detect among wildlife, minimizing opportunity for development of behavioral strategies to avoid avalanche hazards in areas and periods of snowpack instability.”
Goats are an indicator species for high country ecosystems, White said, and research has often not focused on them. “Mountain goats are just an iconic species. They’re sort of sentinels of health and function of alpine ecosystems, and so it’s really just a fascinating species to work on and provides opportunities to learn more about our alpine ecosystems.”
Goat country ranges from the Northern Rockies through Canada and into Alaska. Because the animals inhabit craggy areas that are difficult and dangerous for most humans to access, goats “have always been among the least studied large mammals in North America,” White said.
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