Northern flying squirrels are arboreal rodents with large eyes, round ears and soft, thick fur. They have light brown backs and off-white bellies. A loose flap of skin runs from their front to back feet and allows for the amazing mode of transportation implied in their name. Flying squirrels launch and then spread their legs to glide through the forest canopy. Average glide lengths are 40-50 feet, but can range to just over 200 feet.
Northern flying squirrels are distributed across the forests of Canada and Alaska (see map). The Kenai Peninsula is generally included in the flying squirrel's distribution. However, flying squirrels have never been verified on the Kenai Peninsula. There are no museum specimens, none reported in scientific literature, and no possible sightings reported to Kenai Refuge staff from the public.
Flying squirrels have been verified in the Anchorage area. Perhaps flying squirrels have not been able to travel here from Anchorage. The Kenai Peninsula is connected to the mainland by a 9-mile strip of land called an isthmus. The small size of the isthmus creates a bottleneck. The habitat on the isthmus is dominated by Portage Creek, steep alpine slopes and glaciers, and could be a barrier for flying squirrel dispersal. Six other small mammal species that occur on the mainland have also not been documented on the Kenai Peninsula.
Alternatively, flying squirrels are here, but are not being detected. Another small mammal, the least weasel, was first verified on the Kenai Peninsula in 2009, despite extensive collecting efforts over the past 100 years. Flying squirrels are nocturnal and secretive. Generally, they are observed with a spotlight when they visit bird feeders, when den trees are cut or disturbed, or gliding from tree to tree at the height of summer when dark hours are scarce.
I worked for nearly three years on a flying squirrel study in Southeast Alaska. So, I was particularly excited when Kenai Refuge Biotech Todd Eskelin found possible evidence of a flying squirrel on the refuge. Todd was reviewing photographs from camera stations deployed this summer as part of a brown bear population estimate. For the brown bear study, barb wire was placed around a cache of piled sticks with a smelly lure attractant. Bears needed to go under the bard wire to investigate the cache, scraping off hair which we collected for DNA analysis. The camera stations are being used to estimate the number of bears who visited the area without leaving any hair for analysis. The cameras took a picture of the cache every minute.
Remarkably, Todd noticed a small, flying object in the corner of one of the 200,000 plus photos he reviewed. The object appeared in a photo taken minutes after sunrise and then disappeared in the photo taken one-minute later. The cache was located on the refuge on the edge of a meadow near the Funny River. The object is brown above, creamy colored underneath, slightly convex and tent-shaped, and with small pink appendages. The object is also grainy and pixilated in the digital image.
When I saw the object, I immediately thought it was a flying squirrel. I consider myself somewhat of an expert because I have had the unique experience of working on a project where I measured flying squirrel glides. I carefully watched every flying squirrel that I caught to measure the length, take-off height, and landing height of their glides. In one summer on the Tongass National Forest, I measured 168 glides and witnessed many more. Although I had trapped and radio-tracked flying squirrels for 2 years prior to the glide study, I was truly awed that summer by their aerial abilities. Flying squirrels can change direction mid-flight, navigate around trees, and parachute stall for landing by adjusting their body shape and using their tails as rudders.
To me, the shape, coloration, and pink appendages of the object in the photo have a flying squirrel gestalt or appearance. My co-workers on the refuge are not as convinced. Other guesses include a moth, a bird, and a smear on the camera lens. I have shown the picture to other flying squirrel researchers who believe that the object looks like a flying squirrel, but some question whether a flying squirrel would glide into an open meadow during daylight hours. Perhaps it was visiting the cache; flying squirrels do eat carrion and have a keen sense of smell.
In the end, the photo will never be conclusive. Here at the refuge we will continue to debate and look for other signs that flying squirrels are here. If you see one, please give us a call!
Added note: Refuge Notebook readers may recall our 2001 article on the puzzling "black ring condition" on birch trees in the Finger Lakes - Swan Lake Road area, which some suggested could have been caused by flying squirrels foraging on the sweet inner bark of small birch trunks. We have not observed any fresh examples of this kind of girdling damage since 1999. The article can be viewed at: http://kenai.fws.gov/overview/notebook/2001/apr/20apr01.htm.
* n n
Dawn Robin Magness is the GIS Manager and a Fish & Wildlife Biologist at the Kenai National Wildlife Refuge. Prior to working on the refuge, she worked as a field biologist in Southeast Alaska, Interior Alaska, and on the Alaska Peninsula.
* n n
Previous Refuge Notebook articles can be viewed on the refuge website at http://kenai.fws.gov/. You can check on new bird arrivals or report your bird sighting on the Kenai National Wildlife Refuge Birding Hotline at 907-262-2300.
Peninsula Clarion ©2014. All Rights Reserved.