Squirrel Chatter

This week on Dispatches from the Field, we welcome Sarah Westrick, a Ph. D. student at University of Michigan who shares her experiences at Squirrel Camp! For more about Sarah, check out her bio at the end of the post. 

As a biologist, I’m enamored with nature. Learning more about the natural world around us is what drew me to the field, and biological fieldwork provides some amazing opportunities for me to connect with the natural world. I am lucky to be participating in an incredible long-term field biology program as a third-year PhD student in Dr. Ben Dantzer’s lab at the University of Michigan.

The view of our study grid from the Alaska Highway, St. Elias Mountain Range in the background. The boreal forest in this area is predominated by white spruce. (photo by: Sarah Westrick)

The Kluane Red Squirrel Project (KRSP) is an active research program focused on understanding the ecology, evolution, behavior, and energetics of the North American red squirrel. Since 1987, when Dr. Stan Boutin at University of Alberta established the project, KRSP has grown into a large collaborative effort between the University of Alberta, McGill University, the University of Saskatchewan, the University of Guelph, and the University of Michigan.

“Squirrel Camp” is our field research site, located in the boreal forest along the Alaska Highway in the Shakwak Trench near Kluane National Park in the Yukon Territory, Canada. The boreal forest in this region has been studied since the 1970s by researchers on the Kluane Ecological Monitoring Project, including Dr. Boutin, and continues to be well studied by ecologists from all across Canada and the US.

Working at Squirrel Camp is an incredible experience for many different reasons. One of my favorite parts of doing fieldwork in this region is the chance to really get to know the land we live on and the ecosystem we work in. When you’re out in the forest every day, you learn about the plants and animals intimately. I believe one reason the boreal forest of the Yukon has been studied for so long is its ability to excite ecologists’ natural curiosity. Questions about the ecosystem can come quickly to an inquisitive mind wandering the area.

At Squirrel Camp, we have multiple active study grids in the forest. Each morning “squirrelers” head out to their respective grids to monitor the red squirrels living in that patch of forest. Although the grids become familiar old friends, each day when you go into the forest you never know exactly what you’re going to see. You may see arctic ground squirrels alarm calling, encounter goshawks hunting, or accidentally flush out a mother spruce grouse and her chicks.

An ear-tagged North American red squirrel rattling, a territorial vocalization. Both male and female red squirrels defend their cache of spruce cones by rattling. (photo by: Juliana Balluffi-Fry)

This past summer was my third field season at Squirrel Camp. One day in July, I went out in the forest expecting to have an easy morning live-trapping my target squirrels. Each squirrel defends its own territory and can typically be trapped there, allowing us to monitor its reproductive status throughout the breeding season. Preoccupied by my thoughts, I moved between two of my trapping locations on autopilot, taking a trail well worn by many squirrelers past. As I neared my destination, I began to hear the familiar barking call of the red squirrel, a common sound in a forest with ~2 squirrels per ha.

Canadian lynx in a tree chasing a juvenile red squirrel. Lynx are very cryptic in the boreal forest and can be hard to spot – this lynx is midway up the tree under the witch’s broom. (Photo by: Sarah Westrick)

Not giving it much thought, I continued down the trail. The barks got louder and more frequent. Multiple squirrels joined in the chorus. At this point, I was curious to see who could be causing such a racket and if it meant there was a shift in the red squirrel social neighborhood. My eyes searched the trees for the telltale wiggling branch of a spruce tree or a small furry red tail darting between branches, but I couldn’t find that search image. Instead, I found a much larger furry form in a tree about 10 m away: the long legs, tufted ears, and bob tail of a Canadian lynx. I stopped dead in my tracks, staring, and the lynx looked back at me, panting. We took each other’s measure. After a few seconds, with me fumbling for my camera, the lynx decided to move on and jumped out of the tree, trotting into the forest.

While seeing lynx from a distance is not uncommon in our forest in the winter, we hardly ever get near this cryptic predator in the summer, as they move with stealth and blend into the trees before we can see them. But while the stealthy lynx is difficult for us to see amidst the leaves and spruce needles, to a squirrel it’s critical to spot a lynx before it ambushes them.

A 25 day old juvenile red squirrel with ear tags. Each squirrel in our study has two unique ear tags to identify individuals throughout their lifetime, as well as colors in each tag to identify individuals from a distance. Colored disks differentiate juveniles from adults. (photo by: Juliana Balluffi-Fry)

After giving the lynx a few seconds to walk away, I approached the tree he was in and found one of our juvenile squirrels frozen atop a witch’s broom in the tree, having narrowly escaped becoming lunch for the lynx. In a nearby tree, his mom was responsible for part of the racket that had attracted my attention in the first place. She was still barking like mad and the neighbors were still in an uproar. It’s not often we squirrel researchers observe a predation event – or a near-miss – and I appreciated being privy to this part of the ecosystem that we rarely get to witness.

To top it off, this wasn’t just any random lynx in the boreal forest; this lynx had a blue tag in his right ear. A group of my colleagues at Squirrel Camp had trapped him the previous winter to tag and take a DNA sample. (Squirrel Camp is in fact a multi-purpose field camp: ss our “squirrel season” comes to a close each year in late fall, the Lynx Crew, as we affectionately refer to them – to differentiate them from the Hare Crew (studying snowshoe hares) – moves into camp to track the abundance and behavior of this elusive predator in the ecosystem.) This particular lynx had been followed through the winter farther west down the Alaska Highway, but had since made his way east to our squirrel study grid.

A vigilant red squirrel ready to run up the tree in case of danger (photo by: Juliana Balluffi-Fry)

To me, this encounter was a reminder to savor the special moments in the forest while doing fieldwork. Even through the stressful, frustrating moments in the field, I can always find some part of the ecosystem to ground me. Not many people are fortunate enough to be in the forest often enough to develop such a connection to the land and the ecosystem. Now I walk the forest with open ears, listening closely to my squirrels, and open eyes, scanning the trees for surprises.

 

Sarah Westrick is a PhD student at University of Michigan in the biopsychology program. Her research focuses on maternal behavior and physiology in red squirrels. She received a BS in Zoology and Biology from Colorado State University, where she worked on the behavior and neural mechanisms of Trinidadian guppies. You can learn more about her work at her website: sewestrick.strikingly.com or follow her on Twitter @sewestrick. If you’re interested in working with KRSP, the Dantzer Lab is currently seeking graduate students to start in Fall 2018 – check out Dr. Ben Dantzer on Twitter @ben_dantzer. For more information on the Kluane Red Squirrel Project, check out our website: redsquirrel.biology.ualberta.ca and on Twitter: @KluaneSquirrels