Cascadia Wildlife Blog
News from the Wolverine Tracking Project and more
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Rain in the valley, snow on the mountain, and an undeniable bite to the wind! Winter is just around the corner. Much of the forest is settling in for the long seasonal slumber. The trees and perennials are steadfastly storing their summer bounty below ground, seeds are stored away for spring growth, and animals are changing their behaviors in preparation for the snow. Whether you are one to spend these cooler days like black bears and other forest hibernators, tucked away under blankets or by the fire with a book, or if you are one to brave the elements - we hope you are looking forward to the new season as much as we are!
Learn more: Community Clubs camera surveysBoth our summer camera and scat surveys are coming to an end, but we are still busy collecting photos and genetic samples from the forest. As we transition to winter, we are excited to share some of our final findings from the summer season with you. The first images we want to share with you are of one of our striking target species, the Sierra Nevada red fox!   Top and bottom: A Sierra Nevada red fox explores an alpine camera site with Mt Hood in the background These are some of best Sierra Nevada red foxes photos we have ever received! You can clearly see the red coat of this fox in the morning light, as well as Mt Hood in the background. We have detected Sierra fox at this alpine site consistently throughout the summer, although the photos have so far only been at night when foxes are more active. This camera site has been taken down for the winter, so these images were a wonderful send-off from such a beautiful site. During the winter, we much more commonly detect Sierra foxes below treeline than in the summer, and we hope to get to see this fox again soon! We also received many, many photos of coyotes this season, but none quite so investigative as this individual...
Top to bottom: a coyote rolls on scent bait placed at a camera site This individual rolled around this rock face for just under a minute. Mammals (from coyotes to bears to ungulates and more) use scent as a way to communicate. Our smelly camera sites provide a great opportunity for communication from rubbing parts of their body or by marking with urine and scat. The most clear kind of scent communication is when the animal is attempting to deposit its own scent on something else, and the animal will roll or rub its scent glands onto a variety of surfaces. Animals will scent mark with all parts of their body, including their backs, necks, heads, and faces. However, sometimes mammals will also try to get the scent from something else (usually another animal) deposited on itself. When an animal covers itself in the scent left by other animals, this isn't exactly communication. We actually don't know exactly why they do this! But we speculate that this occurs when an animal wants to mask their own scent, perhaps to hide their scent when they hunt prey. We suspect this is what this coyote was doing. Maybe this individual was about to go off and find itself some dinner! The individual made sure to come check out the camera after they had a thorough roll around. Check out the whole video here.
Left and right: A coyote checks out one of our trail cameras We also received many images of black bears this past month, including this individual that had a similar reaction to the bait as the coyote.
Top to bottom: a black bear rubs it's face against a rock face This bear also seemed intrigued by the bait, but instead of rolling their entire body in it, they rubbed their head against the smell. In general, bears are much more conservative rollers than coyotes. Where a coyote might roll with enthusiasm, a bear might be content with a cheek rub. Along with canines and black bears, our cameras also detected some felines, including a mountain lion.   Top and bottom: A mountain lion walks across a log And some bobcats.
 Top: Bobcat eyes reflect in a night-vision image. Bottom: A bobcat walks through a camera site Both of these big cats do not hibernate and will continue to hunt throughout the winter. Both cats are generalists, meaning they can prey on a wide variety of animals, so their diet will shift to prey that is more attainable throughout the winter months. While many small mammals such as ground squirrels and marmots hibernate during winter, other mammals such as snowshoe hares and mice stay active - great food for our bobcats, and they are content to stay at higher elevations throughout the winter where this food is plentiful. Ungulates (deer and elk) will also stay active through the winter, though they head to lower elevations where there is more opportunity to forage. Mountain lions, who prefer ungulates over other foods, also follow them down the mountain. Speaking of ungulates, many deer walked past our cameras. Bucks, does, and fawns all made an appearance.
 Left to right, top to bottom: A doe walks through a camera site, a fawn walks through a camera site, a buck with new antlers sniffs around a camera site Throughout autumn deer fawns were losing their spotted summer coats and gaining their adult winter coats. But don't let the coats fool you! The youngins will stick by their mothers side for one to two years before going out on their own. Every year, bucks grow new antlers. During a bucks first year, they will just grow little antler nubs, or buttons - hence their name of "button bucks." As a yearling, they will begin to grow their first set of antlers. These antlers will typically be smaller than the antlers of older adults, as they are often just a couple of spikes with little to no branching. You can make out in the photos that at this point, this gent's velvet has shed and their antlers are done growing, completing what may be their first rite of passage into adulthood! Genetics and health also play a role in how large or small a buck's antlers are each year - some yearlings can grow large antlers, while some 5 year olds still just have the spikes. Along with deer, our cameras also detected quite a few elk. Many of these elk were traveling with a much larger group.
Top to bottom, left to right: Elk cows walk through site, elk cows and fawns walk through site, an elk bull walks by the camera, an elk cow with fawn looks at trail camera, elk cows and fawn walk though camera site For most of the year, elk stay in same sex groups, or groups composed of cows and calves. Throughout the year these herds can get very large, sometimes with more than 200 members. However, from August to early winter dominant bulls will follow groups of cows. These harems are formed during mating season, and will have 5 to 20 cows and one or two bulls. A dominant bull is a bull that is in their prime, somewhere between about 5-10 years of age. Bulls breeding success will peak at age 8. These bulls will protect their harems from other bulls. Older and younger bulls will stay on the periphery of these large harems or find their own harems closer to winter. Our cameras also detected some mammals, and a first!! 
Top to bottom: A mink explores a log For the first time in Cascadia Wild history, a camera detected an American mink! Minks are semi-aquatic and feed on a diet consisting of rodents, fish, frogs, and birds. They are most often nocturnal and will almost always look for food at night. Minks do not hibernate, so this new friend will be looking for food all winter (when they're not bundled up in their burrow!). Our cameras also detected some of our usual small mammals including skunks, golden-mantled squirrels, western gray squirrels, and a Douglas squirrels.
Top to bottom, left to right: a skunk, a golden-mantled squirrel, a western gray squirrel, and a Douglas squirrel. The Douglas squirrel (bottom right photo) has a much shorter tail than is expected. Though tails serve a few functions, one of the most important functions of a squirrel tail is balance. Squirrels use their tails for balance as they scamper through the brush or jump from tree to tree. This partly explains why tree squirrels tend to have longer tails than ground squirrels, and flying squirrels tend to have even longer tails than tree squirrels. It is not unusual for a squirrel to lose part of their tail. Squirrels have many natural predators, such as snakes, hawks, raccoons (and more) who will bite down on a squirrel's tail, and squirrels can also lose part of their tail to snags in trees or fences. When met with a predator or snag, a thin covering of tail skin and muscle can be torn away without life-threatening impacts. scat surveysVolunteers have been hard at work on scat surveys this month! So far this season, volunteers have collected at least 9 potential wolf scat samples and 15 potential fox scat samples! Here is some potential wolf scat from a recent Wolf Scat Survey.  When identifying wolf scat, three important factors are shape, size, and contents. We look for hair and/or bone in the scat, which is indicative of a carnivorous diet. Canines are opportunistic and can have seeds, grasses, berries, and even insects in their scat! However, wolves are especially carnivorous canines, and we especially expect to see hair from ungulates, their preferred diet. A twisted shape with tapered ends is also characteristic of canines, and for wolves we look for an average diameter of at least 1.25 inches - large enough to exclude all coyotes and most large dogs. In this sample, there seems to be some matted hair in the scat, which is positive sign. Even the largest dogs tend to have vague contents, reflecting a uniform diet of kibble and other dog foods. The general shape of this sample fits, too. The largest piece has a twisted shape and the ends are tapered. The average diameter might be just shy of 1.25 inches, meaning perhaps this was a very large meal for a coyote, or perhaps a wolf had a small meal. One of our volunteers also found some potential Sierra Nevada red fox scat.  This scat displays the canine characteristics of shape and contents, and it also is indicative of fox scat due to its smaller size: under 1/2" or the size of your pinky. Both scats, along with the several others that volunteers have collected over the season, are potentially valuable sources of information about these important canine carnivores that call Mt. Hood National Forest home. While the snows on the mountain may have concluded our alpine fox scat surveys, there may still be a few more good weeks of wolf scat surveys left. As we head into winter, though, we will be collecting less scat and transitioning to seeking out tracks. Lots to look forward to! Until next time, stay safe, stay warm, and enjoy the season.
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