I have been using the game cam to monitor a den site in the forest behind T.A. for over a month and have gotten a large volume of images including multiple species. This den seems to serve more than one purpose. I have observed small rodent and porcupine tracks entering and exiting the mouth of the den indicating that these animals are using it for shelter. The skunks shown have spent some time in and around the den as well. Our native species of skunk is officially referred to as the striped skunk but their coloration his highly variable. Check out how much darker one individual is than the other in the videos below. I have come across a broad spectrum of color patterns on skunks in my travels from all black to nearly completely white.
Both of these skunks spent some time in the den before moving on.
In addition to the skunks, I have gotten photos of Coyotes (Canis latrans), gray foxes, and red foxes. To these creatures, the den site seems more like a marking post than anything else. The entrance to the den is too small to fit any of these larger canids. Scent marking is common with many of our native mammals. It is an effective way to communicate age, sex, and overall health with other members of the same species as well as mark territory. This behavior is extra important for the foxes in the area as they are at the height of their breeding season right now and are working to establish a territory to raise their kits in the spring.
(Top to Bottom) Coyote, red fox and gray fox visiting the same den site hunting small rodents and scent marking.
Watch as this gray fox sniffs around the den site then begins to scent mark as it walks away.
Nate, an enthusiastic second semester wildlife student, asked to tag along on a check of the game cameras during his study hall today. I happily obliged and we made a great discovery! We have finally confirmed the presence of porcupines (Erethizon dorsatum) in the T.A. forest. After finding tracks back in January with my semester one students, I have been using a game camera to monitor a suspected porcupine den in a small hemlock grove for a few weeks now. We still haven't captured a porcupine using the camera on the den but we did even better this morning. As we arrived in the vicinity of the den, we noticed a large number of hemlock branch clippings in the fresh snow under one tree in particular.
Check out one of the partially nibbled hemlock branches that clued us in to the porcupine's presence
A quick look upward revealed the characteristic dark "blob" near the top of the tree. We had finally found the porcupine. This individual hasn't been on the ground since our most recent snow and was only evident because of the food scraps it has been dropping from the tree. Nate was extra excited as this was the first porcupine he had ever seen in the woods! Eastern hemlock (Tsuga canadensis) is an important source of food and shelter for porcupines in the winter. These winter "resistors" rely heavily on hemlock needles for food and leave plenty of evidence of their presence to the observant eye. The hemlock's thick canopy not only provides food but also protection from wind and snow.
Can you make out the porcupine resting in the tree?
On a related note, I observed my first ever set of fisher (Martes pennanti) tracks in the T.A. forest while checking cameras on Wednesday this past week. The fisher is the only effective predator of porcupines in Maine. They take them on by biting at their face where they have no quills. Porcupines are particularly vulnerable to fishers while on the ground but are not completely out of danger in the trees either. The fisher is equally adept at hunting in the canopy. Hopefully we can capture this apex predator on the game camera in the near future. Stay tuned.....
Fisher tracks in the snow behind T.A. Note the characteristic bounding gait pattern.
My semester one Maine Fish and Wildlife students could tell you that creatures in Maine have three options to survive our typically long, brutal winters. They can Hibernate, Migrate, or "Resist". It seems ecologists are locked in a never ending battle to define a true "Hibernator" and as the argument stands today, Maine has only a handful of true hibernators. Woodchucks (Marmota monax), little brown bats (Myotis licifugus), and the black bear (Ursus americanus) would fit into this elite group. Although, some people are still skeptical about awarding this title to the bear. In order to be considered a true hibernator, a creature must slow its metabolism and body temperature down to levels so low that it cannot easily wake up. Those backyard woodchucks notorious for munching on freshly planted gardens in June are truly amazing creatures. Their heart rate can dip as low as 4-5 beats per minute during their long winter slumber! Sorry folks, our beloved groundhog day is an elaborate hoax. There is simply no way a wild groundhog (a.k.a. woodchuck) could wake up from its hibernation as quickly as ol' Punxsutawny Phil.
There are many mammals in Maine that are assumed to be hibernating because they seem to disappear during the winter only to show themselves again in the spring. The striped skunk (Mephitis mephitis) is one of them. Skunks remain in dens for the majority of the winter and are able to lower their body temperature a few degrees but nothing close to the woodchuck. Skunks remain mostly dormant living off their fat stores but during warm spells they can be observed out and about foraging for food.
This skunk seen above is taking advantage of a recent warm spell by getting out in search of food.
A classic Maine winter resistor is the red fox. They are awake and active all season. Wild canids including the red fox walk in a manner that is often described as "Direct Register". This is when an animal's back foot lands exactly in the track made by its front foot on that side. This method is also referred to as "perfect walking". It often amazes me how strait a set of fox or coyote tracks can be compared to the sloppily laid impressions from your average house dog. Over millions of years, wild dogs have evolved to conserve energy in a variety of ways. It makes sense that direct register is a simple way to move more efficiently in deep snow. Foxes have large home ranges and must cover a lot of ground to find enough prey to survive our winters. Without this perfect gait, wasted energy would spell certain doom. While people walk on two feet making this method difficult, we obviously appreciate the value of direct register. Who hasn't utilized another person's previously laid tracks when wading in deep snow?
Watch closely as this red fox steps perfectly in the tracks laid by its front feet.
Last Monday night, with the help of Sunday dinner leftovers, I was able to capture three species on the game camera behind T.A. Red Fox (Vulpes vulpes), gray fox (Urocyon cinereoargenteus), and raccoon (Procyon lotor) were all captured in photos and video. It was exciting to see a pair of red foxes on camera at the same time. Red foxes are largely monogamous and I can't help but wonder if this is a mated pair? We will have to keep our eyes out for red fox kits this spring! In another interesting note, I have been using my game camera for four years at home (just across Route 1 from T.A.) and have captured countless images of gray foxes. I have not once observed a red fox in my yard. It seems that the gray foxes in this area are better at assimilating into backyards and neighborhoods while the red foxes prefer less human disturbance. This would explain the dramatic increase in gray fox numbers in Southern Maine over the past decade. In fact, they are the only Maine furbearer whose harvest levels have increased in that time.
The video above shows the second red fox arriving on the scene.
The raccoon captured on camera the same night is "healthy" to say the least. This mild winter is certainly a welcomed change from last year from most wildlife's perspective. This is not the first time raccoons have been documented on T.A. grounds. There was a regular visitor to the squirrel feeding station last fall during our research period. My lab aides would arrive to find the feeder completely empty each morning with the SD cards full of pictures of the raccoon helping itself to the the corn and sunflower seed mixture.
A healthy raccoon can be seen sniffing around for leftovers in this clip.
The gray fox showed up briefly during the early morning hours but provided a great video clip. The custodial and residential staff have all reported regular gray fox sightings around campus in the early morning and late evening hours over the past few years. The amount of tracks right on campus after our most recent snow was evidence of their willingness to cruise the campus at night in search of any food items left along the walkways over the course of the day.
This gray fox was a bit late to the party but stopped in to scent check where the red foxes had already cleaned up.
