A few years ago, trapper Jim Stickler was walking along the Haines Highway near the Council Grounds pullout around Mile 20 when something caught his eye.
There were bear tracks in the snow that led to a partial carcass of a chum salmon. The bear had snacked on part of the fish and left the rest on the ground. That’s normal behavior for bears who have plenty of fish to choose from in the Chilkat Valley and often only eat the choicest parts of chum.
What was unusual for Stickler, who can read tracks like a storybook, was another set of tracks around it: lynx.
The tracks indicated an animal had likely scavenged some of the remains of the fish before darting back into the woods.
A group of citizen scientists in the Chilkat Valley is now working on documenting the behavior with camera traps and fur analysis. If they are successful, biologists say it might be the first documented case of lynx eating salmon anywhere in the world.
Liz Hofer is a longtime wildcat biologist who splits her time between Haines and the Yukon Territories, and is leading the Chilkat Valley project. Understanding lynx diets is just one piece of the project, which aims to understand the population dynamics of the valley’s only wild cat species.
“Lynx feeding on salmon hasn’t been documented anywhere in the world — not that I know of,” Hofer said.
Photo courtesy of Peter Mather.
The group has limited resources, but Hofer said it’s driven by the excitement of learning more about the elusive predator. Lynx are adapted to and dependent on snowshoe hares for food. Scientists around the state are working to understand how lynx adapt to low hare numbers. They say finding hard evidence of lynx scavenging on salmon would be important.
“It would be really interesting to see if salmon are a significant alternate food source,” said U.S. Fish and Wildlife Service biologist Mark Bertram, who isn’t involved in the Chilkat Valley study. “If they are feeding on carcasses that would be outside of the normal mold.”
Need for the study group
Hofer has studied wildcats around the world for decades with an emphasis on tracking. She said driving to the pass from Haines to the Yukon and back, as she often does, made her start thinking about what might drive wandering lynx into the Chilkat Valley from their population strongholds in the Interior.
Lynx populations can vary dramatically year to year, a population cycle largely dependent on snowshoe hare populations, which are usually their main prey.
In years following a drop in hare populations, radio-collar studies show that some lynx in an area start to wander far from their home hunting grounds. The methods of their wandering are still being studied, but they’re known to cover impressive distances, sometimes more than 1,000 miles in a few months.
“We’ve had animals collared in Bettles dispersed to Chukchi Sea,” said Bertram, who is leading an ongoing study of some 50 GPS-collared lynx. “Sometimes they’re in a straight line. They’ve crossed Yukon, McKenzie rivers, so they basically have no barriers.”
A long held theory is that when prey declines in one area, lynx move in a sort of wave to an area where hare populations are still robust. Recent GPS-collar research has chipped away at that theory, showing that lynx movements appear more or less random.
“There wasn’t a good pattern, it was almost like they were prospecting for new territory,” said Alaska Department of Fish and Game Biologist Dave Saalfeld, who is studying lynx in Southcentral Alaska.
But some lynx — it’s not entirely clear what percentage — stay in their home areas, wandering around in hunting grounds that usually range from about five to 15 square miles appearing to be waiting for a hare rebound.
A few years ago, a local group asked Hofer to write a column about lynx in the Chilkat Valley, and she realized that the entirety of lynx research in Alaska was done on Interior populations.
With that knowledge, Hofer wanted to know more about coastal lynx populations. Were they primarily wanderers escaping a population crash in the Interior? Or is there a consistent resident population in the valley, and if so, what do they eat when there aren’t a lot of small game in the area?
Hofer gathered a group of a handful of interested residents, former scientists, and trappers. She looked into the existing data on lynx, which was primarily limited to a few game camera images, and trapping records. The records showed that since the 1970s, the number of pelts turned into Fish and Game in Haines to be sealed has ranged between zero and seven, roughly following a 10-year cycle, presumably matching hares.
But the trapping records hold limited value. For one, it’s not guaranteed that all pelts are turned in to Fish and Game, despite legal requirements to do so.
Also, trappers often don’t target lynx in years where they believe the populations to be low. Instead, trappers like Stickler set small leg-hold or Conibear traps for wolverines and martens. If they start catching lynx in a year, they might target them. Stickler said he traps lynx exclusively with snares instead of folding traps. In any case, it means the data doesn’t fully account for the population dynamics.
Determining a population
Hofer and her group hope their study will fill in some of the gaps in knowledge about the coastal lynx population.
Last year, the group got a small donation from Alpine Bakery, a bakery in the Yukon Territories, to set up game cameras around the Chilkat Valley.
Hofer said in all, the group now has access to about 34 cameras, which are roughly laid out in a grid. They try to visit the cameras twice a year to upload images. Going into their second full winter, they still don’t have a lot of clear images due to the difficulty of capturing lynx in low winter light, as well as the fact that the current population cycle is at a low after good years in 2020 to 2023.
“We knew the population was going to drop, but at least it would give us some idea,” said Hofer.
Aside from the game cameras, the group is also working on a dietary analysis based on hair samples from lynx. Trappers around the region and in other Southeast communities have reached out to share hair samples from the high population years of the past few years that can be tested for chemical composition to determine what they are eating. The group is also working to gather its own samples with hair snags on well-used lynx trails that could give insight into how diets change in low lynx years.
Hofer said a biologist who runs a lab in Wyoming has volunteered to do that analysis. They could have results by January that could decisively prove whether lynx eat salmon as a significant part of their diet, though it would leave open the question of whether it is primarily scavenging dead salmon or catching live salmon.
Despite its limited resources, Hofer said the group is committed to a long-term study that could supplement other shorter term research being done in the state.
“If there’s something very interesting, perhaps it would attract a bona fide academic researcher with more resources,” said Hofer.
Correction: This story previously misstated the name of the bakery that donated to the lynx project