Note - this web page has not been modified since 2003

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Here we are placing a nesting box. We try to place our boxes at heights between 4 and 6 metres.	We record the exact location of each box with a GPS unit. Myriad other data are recorded. Northern flying squirrels prefer older-growth coniferous forest like this Bruce County forest pictured above.	Each box is uniquely identified. Above is a label destined for box #119 which will be placed on a property held by the Grey-Sauble Conservation Authority. Here are a bunch of nesting boxes destined for placement on Saugeen Valley Conservation Authority lands.
We recycle! Our nesting boxes are made from donated wood reclaimed by a local timberframe home builder.	Kids, can you guess who destroyed the nesting box on the right? Despite our best efforts to build our boxes without leaving traces of salt (from sweaty hands), some boxes will inevitably fall victim to, you guessed it, porcupines ... usually resulting in our having to replace the complete box. This is why we don't use plywood for our box construction, as the glues within the plywood contain sodium compounds (salt)!
A look inside a nesting box that was being used by a solitary male in July of 1997. Males tend to construct low-loft, rudimentary nests. Females (gravid or with young) tend to build high-loft, finely shredded nests.	At birth, northern flying squirrel pups weigh between 4 and 6 grams. Their internal organs are visible through their skin. These four pups are approximately 6 days old. Except for a few short vibrissae (whiskers), they were born hairless, "blind" and unable to hear sound. Their eyes are sealed shut, as are their ears. They will grow very rapidly, thanks in part to a very attentive mother.	At approximately 11 days of age, these 6 northern flying squirrel pups are showing a distinct darkening or the skin on the head and back. Toes begin to separate, and short hairs begin to appear on the head, shoulders and chest. Soon their ear canals will begin to open.
At about 20 days old, pups will react to sound.This little guy is between 3 and 4 weeks of age - eyes are almost ready to open and upper and lower incisors have erupted.	As a rule, northern flying squirrel pups in Grey & Bruce are born during the late April/early May window.	This pup (see pic on left) had a case of "the sleepies". A common occurrence, we find that some flyer babies at this age would simply rather just sleep - regardless of handling!
The "spread reflex" is an innate response. Scientists speculate this facilitates a softer landing, should a young flyer fall from its nest.	Here is a look inside a nesting box just brimming with juvenile northerns who are almost qualified for their "G1 gliders licence"! They began leaving the nest for very short periods at about five weeks of age. This bunch (4 of 'em) is between 6 and 7 weeks of age - almost completely weaned and ready to take on the world.	Setting a live-trap. We set our traps close to nightfall. This helps to reduce non-target animal catches, especially diurnal red squirrels. A closed trap is a useless trap unless it contains the target animal!
This little guy is about 5 weeks old - not quite ready for prime time! Note the length of the snout in relation to body size, compared to that of an adult. Some recent research has indicated a correlation between skull shape and age.	Here he is again. Flyers are very difficult to handle as they are so small and fragile - not recommended for the faint of heart! Adults can and will bite.	Employing a precision digital caliper, we measure various parts of the squirrel (i.e. nasals, tail length & width, body length, ear (from notch), hind foot length, and skull length & width).
We weigh every squirrel with a Pesola 300g spring scale. Flyers under 6 weeks of age are weighed with a digital platform scale.	20 to 30 hair shafts with roots are taken from each animal and submitted to OMNR's Landscape Genetics division in Peterborough for micro-satellite DNA analysis.	This is an aggregate box. Some of our aggregate boxes (like this one) are fitted with high-tech infrared video cameras that allow us to monitor and record behaviours within the aggregate. Fascinating TV without commercials!
November 1999 Here is a video-capture still of northern flying squirrels inside an aggregate box during "play time". And they love to play! They will tumble about for hours at at a time. December 1999 This video-capture shows a squirrel on its way out of the nest for the night (the access hole is top-right and just out-of-frame).	Active year round, flying squirrels will readily visit bird feeders and feeding stations, as pictured above.	No, flying squirrels cannot walk upright! This photo simply caught one in transition from all-fours posture to climbing posture. Flying squirrels are extremely agile and, like most squirrels, have a wonderful sense of balance.
It can be very difficult to get a decent picture of a flying squirrel "in flight" unless you have highly specialized photographic equipment. If you don't have the funds to invest in such equipment, a fast motor drive is essential.	Pictured is a northern, in "full brake mode", just about to land on a trunk of an eastern white cedar. Because it is so difficult to take good pictures of flyers in the wild, most "professional" photos of flying squirrels are taken under controlled, indoor conditions employing "tamed" subjects.	Hmmm...who is studying whom?
In mid-glide, a northern flying squirrel's patagium is fully extended.
This is a scan made from a 1918 painting by Louis Agassiz Fuertes [1874-1927], a noted American ornithologist and artist.	Photo © by Mark Bloomer The patagium is stretched to its limit in full flight. This allows for the least resistance, which results in maximum speed.	Photo © by Mark Bloomer Notice how the patagium billows like a parachute. This allows the squirrel to "brake" its momentum before landing.
You can barely make out the long vibrissae (whiskers) which, it has been postulated, may aid the squirrel with regard to in-glide navigation through dense bush. When agitated, flyers will stomp their hind feet repeatedly. When fearful, some will groan with each breath.	Note the dark colouration along the edge of the flap of loose skin (patagium). The colour and texture of the fur (pelage) can vary tremendously from squirrel to squirrel. Northern flying squirrels moult once per year, in the fall. Flyers make a variety of low intensity but high frequency sounds (tseeps, chips) as well as louder chuckles, snorts and groans.	In the foreground is the landing (sitz) mark left in the snow by a northern flying squirrel.
Traditionally, determining an animal's presence in winter (by looking for their tracks) is done on the ground. With flying squirrels, however, one can, given the right conditions, determine presence by inspecting tree trunks. Pictured above is a landing mark. Note how close together the forepaws are compared to the hind paws.	This impression in the snow was made by the tail when landing.	blank
The skulls of the southern flying squirrel (left) and the northern flying squirrel (right).	Pictured here are the skeletons of the southern flying squirrel (top) and the northern flying squirrel (bottom). Thanks to Judith Eger of the Royal Ontario Museum for letting me into the ROM's basement archives for an afternoon!	The skulls of the southern flying squirrel (top) and the northern flying squirrel (bottom).
Live-trapping southern flying squirrels in 1999 at Point Pelee National Park with Project Leader Ian Adams (right) a former University of Guelph grad student who was responsible for reintroducing the southern flying squirrel to the Park in 1994. Park Warden Tom Linke (middle) watches intently as does UofG grad student and heir to the next phase of the project, Ewa Bednarczuk. I was there assisting for the initial setup period - it was fun to stay for a week inside the Park and to explore areas where most folks will never have a chance to see. Ian was a "man of the forest" in more ways than one, and was generous with his patience & knowledge. Tom was the assigned project liason for the Park, and what a bonus that was! He got right into the project from the get go. Diagnosed in 1998, Tom passed away from brain cancer in 2005...strong and courageous throughout.	From 1994 to 2003, I spent many hours in all types of weather in observation of flying squirrel behaviours, employing cameras, night-vision optics, and an "observatory in the trees", more commonly called a treehouse. The treehouse location is a 2.5 hour drive from home base. Holding the video camera in the photo (above) is Dr. Jonathan Keeling, Assistant Producer, Natural History Unit, British Broadcasting Corporation (Bristol) at the base of the flying squirrel treehouse (Bruce Peninsula, Ontario, Canada/Summer 2001). John, who has been around the world a fair  number of times, flew over the big pond to check out the wild flying squirrels that visit my treehouse feeding station. Jon was scouting locations for the BBC's and Sir David Attenborough's Life Of Mammals nature program series. John was astonished with the number of flying squirrels, their antics, and the tremendous amount of gliding activity displayed. The "in the trees" viewpoint sealed the deal. Shooting was set for November, 2002. Three film crew personnel would stay for four days to obtain 2 minutes of footage. Sir David, as pretty much everyone involved called him, would arrive and stay for day 2 and 3 of filming. Less than four weeks before shooting would begin, I had to place a call to Dan Tapping, the logistics man for the show. An owl or owls had stopped by for a buffet dinner. I found one dead at the base of a tree, a broken back, likely a "hit and miss" by a larger owl species. I had it stuffed, and it became the first flying squirrel I used in my early presentations. Anyway, Dan's reaction to my statement was a period of quiet followed by a very elegant "Sir David certainly won't like this". In the end, I managed to hook them up to a fellow I had previous email contact with, and who had a somewhat comparable setup. The  flying squirrel footage was indeed shot at this location in Maine. So a good ending after all that!	A NORTHERN FLYING SQUIRREL PREDATOR WANNA-BE An eastern screech owl patiently sitting on one of our feeding station platforms - hoping for a meal. Because this photo was taken mid-winter, all the squirrels were fully-grown adults. These squirrels essentially ignore this owl, even though they are in plain sight of each other, barely 15 feet (4.5 meters) apart at times. The owl follows the squirrels' movements and glides with its eyes. You can almost see the owl licking its lips (if it had any!). Our screeh owl visitors eventually settle for smaller fare such as the nocturnal white-footed or deer mice (Peromyscus sp.). As a rule, adult northern flying squirrels are just too big to handle for these relatively small birds of prey, the owls know it, and the squirrels know it. Not to say that some screech owls won't try. Some will be successful too. There are few absolutes in nature.
PREDATOR These young raccoon kits, sound asleep inside a big snag at Point Pelee National Park in Ontario, will soon learn from their mother that flying squirrel pups are a true delicacy.	PREDATOR This fisher met an untimely death. Fishers are somewhat arboreal and are often spotted chasing flying squirrels along branches. More often, fishers will pull adults and babies out of nesting cavites and devour them post haste.	PREDATOR This massasauga rattlesnake will wait patiently during the night for small mammals to cross its path. The nocturnal flying squirrel will to come to the ground to dig for hypogeous sporocarps and some will end up inside a rattlesnake's stomach.

These "stuffed" specimens are from the Royal Ontario Museum (ROM) collection. The northern is at the top, the southern at the bottom. Both were taken in the late 1800's from Toronto. Needless to say, due to loss of habitat, there are no flying squirrels in Toronto any longer

To learn more about flying squirrels, please visit our companion website:

In many jurisdictions across North America, it is illegal to keep wild animals, injured or not, for any length of time and for any reason, without a special licence. It may also be illegal to transport a mammal for any distance for release. It is advised to speak with your State/Provincial Natural Resources department or Fish & Wildlife Service for information and/or advice. Wild animals can carry deadly diseases and will bite without warning. Never attempt to keep a wild animal as a "pet".