Cascadia Wildlife Blog
News from the Wolverine Tracking Project and more
Happy Spring! While snow and cold will linger around the mountain for a bit, there is an undeniable warmth on the breeze. In the valleys, buds are bursting on trees, spring ephemerals are opening to greet the season, and we welcome all the new growth that this season brings! At Cascadia Wild, we are celebrating the season with offerings of Spring Botany Classes and a new Tracking Challenge!
Our last tracking challenge was All About Squirrels, and here are the Tracking Challenge Winners! Left to right (or top to bottom): Clearest Squirrel Tracks by Graham Hulbert (Tracking Leader); Most Unusual Squirrel Tracks by Alexis and Andrew (Camera Crew); Best Squirrel Sign by Sophie Dimont (WTP Intern).
Meanwhile, winter's not over yet for the Wolverine Tracking Project! Read on for our latest findings from our winter wildlife camera and tracking surveys. wildlife Camera and Tracking surveysWe've had a couple detections - and a couple possible detections - of target species this month! We are excited to share this camera footage of one target species, the Sierra Nevada red fox: A Sierra Nevada red fox enters a snowy clearing to inspect a camera site. We had two separate detections from this camera in the same night, a few hours apart. It is impossible to say whether this is the same individual without genetic evidence, but in both instances the fox in frame was cute and curious! If the sightings are of two separate individuals (of opposite sexes) we hope they are a pair. These images were taken during red fox mating season (January and February), and kits conceived during these winter months will be born between March and May. A Tracking Leader also recently found some tracks that could possibly belong to a Sierra Nevada red fox: Left to right (or top to bottom): A canine trail up a snowy hill on Mt. Hood; a canine track in deep snow is carefully measured. The trail pattern and size of these tracks are right on for fox tracks. However, these characteristics could also indicate that these tracks were made by a coyote or domestic dog. Unfortunately, due to less than ideal snow quality, it is difficult to look for more differentiating characteristics. In an ideal tracking scenario we would look at the shape of the negative space between the toes and heel pad. In domestic dogs and coyotes, this negative space is shaped like an "X". In red foxes, this shape is an "H". This print is a double register - meaning the hind foot has stepped on top of the front print, obscuring the details of the front track. If we could clearly see the front track, we could also look at the shape of the heel pad. In coyotes and dogs, this shape is trapezoidal; on foxes, the heel pad is more "squished" looking and can show up looking more like a horizontal line. For now, we'll have to log this track as "canine" - no matter how excited we might be about the possibility of detecting our most elusive montane fox! This tracker also found some potential Sierra Nevada red fox scat on the same survey: Small scat in the snow, with tape measure and a memo book for size reference. This scat has a dramatic tapered end and is about as thick as your pinky finger, which are both good indicators for fox. However, like the tracks found nearby, the scat is also a little formless which could be due to age, diet, or even the snow. It's hard to know who this scat belongs to based on visual clues alone, but this sample was collected and genetic analysis can tell us for sure. One of our long-time volunteers also sent us these canine tracks, which may belong to another target species, the gray wolf: Left to right (or top to bottom): A trail of probable wolf prints leads off through the snow; a probable wolf print shown up close. When considering canine tracks that may belong to a wolf, the most important consideration is size. Wolf tracks are larger than coyote tracks and much, much larger than foxes. They are also much larger than most domestic dogs, except for large breeds like Great Dane, Mastiff, and Rottweiler. And so, determining who these tracks belong to requires differentiating between large domestic dog tracks and wolf tracks. Compared to domestic dog tracks, wolf tracks typically show a greater distance between the two outer toes (the interdigital space). The toes also point straight ahead instead of out, like they tend to do in dog tracks. Claws are long and pronounced, and thinner than in dog tracks. Wolf tracks also show a longer track with a proportionally smaller heel pad, and the track will show a downward angle in the direction the wolf is traveling, since they do not walk as flat footed as dogs do. Like our possible fox tracks above, however, we don't have enough details to say for sure that these belong to a wolf and not a domestic dog. Details of the trail pattern and context would also be helpful to confirm an identification. Thus, we can only say that these are probable wolf tracks - but still an encouraging sighting nonetheless! We also detected another target species - and this time we are sure of it! These photos below show the fierce mustelid, Pacific marten. Left to right and top to bottom: Several detections show a Pacific marten approaching the bait tree in the center of a snowy camera site. It is unclear if these are the same or different individuals each time. The photos above are from three separate detections of marten at this same site, where they have also been detected throughout the season. Like the Sierra Nevada red fox, we can't know for certain if this is the same individual without genetic data. Martens spend the winter roaming and hunting alone, and the territories of males will overlap with those of females, but males defend their territories against other males. So if these are separate individuals, they may be polygynous partners. This magnificent mountain lion was also documented: A mountain lion stands in a snowy clearing. A rare detection in the mountains in winter, this is the third sighting of a mountain lion at this location this winter. The camera crew even found fresh mountain lion tracks at the site at each camera check! Oregon has a healthy population of about 6,000 mountain lions. Hunting regulations were instituted in 1961, after the population had been decimated to approximately 200 individuals, and thankfully they have since rebounded. Another feline was also detected, the bobcat! The two white spots which visible on the back of their ears are thought to be false eyes which deter predators. Such distinctive markings (as well as the white underside of their tail) may also help trailing cubs follow their mother. Top: A bobcat picks its way through the snowy camera site clearing. Bottom: A bobcat photographed mid-stride. Bobcats have classic feline tracks, with toes that sit in a curve above the heel pad, allowing the space between the toes and heel pad to form a C shape. With a length of 2 1/2 inches, these tracks are too small to belong to a cougar but are just the size you would expect for a bobcat. Left to right: A dainty trail of prints in several inches of snow left by a bobcat; a partially snow-obscured bobcat print photographed up close. Coyotes were regular visitors by night and day, as they have been throughout the winter season. Left to right/Top to bottom: A coyote sniffs around the bait sight clearing and then pauses in front of the trail camera; White Tip (a coyote noted previously at this camera site for her white-tipped tail) watches on as her companion urinates on the bait stump; a coyote rolls in bait on the forest floor; a coyote visiting at night-time stands on hind limbs to thoroughly investigate the bait box; a coyote digs in front of the bait tree while a cohort looks on with interest. The camera sites also documented many, many deer, exemplifying a diversity of age and size found between deer and even within the same herd. Left to right/Top to bottom: Deer of many sizes parade past the trail camera; a deer tentatively steps into a snowy clearing; a deer elegantly pauses with their forelimb raised; two deer dusted with snow walk by; a deer with head lowered enters a sun-dappled clearing. Elk also roam the forest. They sometimes appear on our trail cameras solo, but they can appear in quite large herds, too - especially this time of year. Left to right/Top to bottom: A bull elk shows their profile to the camera; a bull looks away from the camera; a group of elk stand in a cluster looking in different directions. Although snowshoe hares are common sights on our trail cameras, their quantity does not diminish their quality. A hare bounds around a camera site, looking out of frame and at the camera. Snowshoe hares are an incredibly important prey species for many omnivores and carnivores, like two of our target species, Sierra Nevada red fox and gray wolf. In fact, they are such an integral part of the food chain that their population size can directly affect the population of predators in the area. But to catch a snowshoe hare, a hopeful carnivore must have keen eyes and quick paws. In winter, the coats of snowshoe hares often turn from brown to white, to help them blend into the snowy world around them. Also, snowshoe hares can cover up to 10 feet of distance in a single bound, and they can bound away from carnivores at a top speed of 27 miles per hour! Other important prey species include the the California ground squirrel, western gray squirrel, and the Douglas squirrel. Top to bottom: A California ground squirrel runs onto a log and then off a log; two western gray squirrels chase each other towards a stump; a Douglas squirrel runs across the snow. California ground squirrels are known to hibernate during winter, but can emerge from their winter sleep as early as January, though some are not seen until March. Looks like this one in the first photo is an earlier riser! Western gray squirrels and Douglas squirrels are active all winter. In the second photo, we can see two gray squirrels chasing each other - either in a territorial or mating display. We also detected striped skunks wandering by a couple of our cameras. Top to bottom: a skunk walks away from the camera, a skunk walks parallel to the camera We also detected a couple turkeys! Two turkeys have a leisurely walk through a camera site. We hope you are able to get out and enjoy a leisurely, spring stroll through the woods, too.
Thank you for checking out our blog, and be sure to check back in next month for more wildlife news!
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Tracking Challenge!In January, we introduced our first ever Tracking Challenge. Every few weeks this winter, we'll be sharing a new challenge and a series of posts to inspire you to explore your neighborhood, parks, or the mountain for signs of wildlife in the tracks and sign they leave behind. For our first challenge, we asked you for photos of tracks from any animal, no matter who made them. We received some excellent submissions! Here are the winners of the most distinct and the most clear tracks: Most Clear Tracks Left to right/Top to bottom: @buttsuponatime captured these perfect cat tracks! Carlene Blaich (Camera Crew and Tracking Team) found these exceptional snowshoe hare tracks on Mt. Hood. Kurt Zias wins honorable mention for some of the most clear marten tracks we have seen! Most Unusual Tracks Left to right/Top to bottom: Kurt Zias captured these screech owl tracks - notice the mouse trail to the right! Heidi Perry and John Lehne (Tracking Leaders and Camera Crew) encountered a black bear on a mid-winter stroll on Mt. Hood. Honorable Mention: Ray Anderson and Kathleen Baker (Camera Crew) didn't need tracks to identify this backyard visitor!
Explore the Natural worldSpring classes start next month!
Wildlife Camera and Tracking surveysAnd now the wildlife news you've been waiting for! First off, we would like to share our target species sightings this month. Top: A Sierra Nevada red fox sniffs around one spot on the ground. Bottom: a Sierra Nevada red fox walks through the frame, stopping to sniff the ground. These two detections of Sierra Nevada red fox happened at night, about a week apart. They may be the same individual, or they may not. The same individual can look very different in different light settings, at different distances from the camera, and when detected in different modes of motion. Whether are not they are the same individual, both detections show the fox in question was very interested in something on the ground. Another camera also detected another Sierra Nevada red fox… Or did it?! A fox runs through the background of a camera site. This individual is certainly a fox, but these photos were taken outside the expected range of Sierra Nevada red fox, as this site is stationed at a bit lower elevation than they have been documented in Mt. Hood National Forest. This site is also a bit higher elevation than we would typically expect to find a lowland subspecies of red fox. So who could this be? The story of red fox subspecies and populations gets complicated. There are three different subspecies of red foxes in Oregon, the Sierra Nevada subspecies in the Cascades, the Rocky Mountain subspecies in the mountains of Eastern Oregon, and a lowland subspecies that is thought to be non-native in the sagebrush and bunchgrass country. In biology, the usual definition of a species is a group of animals that can breed with each other and produce fertile offspring (meaning their offspring can also have offspring). A group of animals is deemed a subspecies when they form a distinct group that is genetically distinguishable from the rest of the species. They are usually separated from the rest of the animals in the species by some sort of geographic or behavioral barrier. For example, the American black bear is a well known species of bear, but did you know they have 16 subspecies? These subspecies include the Florida black bear, the Louisiana black bear, and the West Mexican black bear, among others. With our red foxes, what first seemed like three distinct subspecies, clearly separated from each other geographically and by differences in preferred habitat, is starting to become more cloudy. Rocky Mountain red fox have been detected close to Bend, Sierra Nevada red fox have been detected near the Willamette National Forest at lower elevations than they were expected to be found, the population on Mt Hood has been found to carry at least a few non-native genes, and now there is a mystery fox found in the no-man's land between where we expected to see Sierra Nevada and lowland subspecies. At this point, we are wondering: Is this individual in the picture above an outlier, either from the Mt. Hood population or from lower elevations? In California, Sierra Nevada red foxes have been documented traveling at lower elevations during dispersal, and dispersal would not be out of question for any fox this time of year. Or, does this detection hint that the range of either Mt. Hood's Sierra fox might be lower than expected, or lowland foxes higher than expected? Further documentation and obtaining genetic samples would be important in our understanding of home ranges, dispersal practices, and connectivity of Mt. Hood's Sierra Nevada red fox and other foxes in our region. We are excited to see what future documentations may tell us. For now, we wish this fox well on their way, wherever they may be going and whoever they may be. Our cameras also detected another canine - the coyote! Left to right/Top to bottom: A coyote looks into the camera. A coyote smells one of our bait boxes. A coyote pops a squat near a fallen tree trunk. A coyote trots through a camera site. These lovable canines remain active throughout winter, and we detect them all over the forest at all different elevations. However, with much of the plant matter being dead or dormant, coyotes have to rely on their skills as a predator and scavenger to find their next meal. With an impressive range, they can roam up to 40 square miles searching for food (though probably not in a single day!). Their thick winter coat helps them stay warm as they look for their next meal. Our next detection is a big predator, much like a canine, but in a much smaller package. Can you tell what species they are? They have a long body, short legs, and a fuzzy face, but don’t let that fool you… A blurry weasel darts away from our bait tree. We detected a weasel! What these small mammals lack in fat stores, they make up for with ruthless survival tactics. Weasels do not have a permanent den, but instead will use their small, long body to sneak into rodent’s dens, prey upon the rodent, and then use the rodent’s den for a nap. They curl up into a ball ball to conserve heat, and once they're rested, they set out again to find new prey. Due to their fast metabolism, weasels need to eat at least five times a day. Now onto our feline friends. First up, the mountain lion! This is our first mountain lion detection this season, or least the back half of one. The torso, back legs, and tail of a mountain lion seem to be walking out of frame. Mountain lions do not hibernate or migrate great distances in winter, meaning they stay in the same general area year-round. With that being said, mountain lions are altitudinal migrants and follow ungulates to lower elevations during winter to retain a dependable food source. Much like us, throughout the snowy months, mountain lions will visually track deer using their footprints in the snow. Much like their feline cousin, bobcats also stay active all winter. Left to right/Top to bottom: The eyes of a bobcat glow in the night. A bobcat dashes by. A bobcat calmly walks through a camera site. For most of the year bobcats are crepuscular, but in winter they transition to being more active throughout the day to have a better chance of finding some diurnal prey. Another important forest carnivore, black bear were detected! However, unlike the canines and felines of the forest, black bear are not typically active all winter. Left/top: A black bear is barely discernible as an outline in the wintry weather. Right/bottom: Bear tracks in the snow. Not only were black bears detected on camera in January, but a camera crew also found their tracks while checking a different camera. It is very exciting to see these bear tracks in such beautiful detail! In fact, these bear track photos WON the Tracking Challenge for Most Unusual Tracks found on Mt. Hood! (See More Tracking Challenge Winners) Left/top: The front right paw print of a black bear. Right/bottom: The left hind print of a black bear. The first photo above shows the right front paw. You can make out all five toes, and below the toes are the palm pad. Black bears also have a heel pad below the palm on each foot, which may not always register, as is the case in this photo. The second photo above shows the left hind paw print. Many a bear track may have been confused with sasquatch (and vice versa!), and you can begin to see why. However, unlike human feet, the inside toe is the smallest and lower than the others, and the "big toe" is on the outside. The hind foot has larger palm and heel pads than the front, and, in this case, the heel pad registered. You can make out the claws and the folds of skin on this bear's foot, too! Now you may be wondering: why is a black bear awake in winter? Bears are not “true” hibernators like many animals that burrow and hole up for winter. In the winter, bears, raccoons, and skunks hibernate by going into torpor, an involuntary state of reduced activity and lowered metabolic rate for energy conservation, but not into a total and extended dormancy like chipmunks, bees, toads, and so on. The overall time a black bear can spend in its den in torpor hibernation varies geographically from 0-7 months, and in Oregon it has been reported as usually lasting between 5-6 months. However, whereas true hibernators like ground squirrels need to wake up every week or so for sustenance and to pass waste, bears can stay in their torpor state without needing to wake for up to 100 days - or they can remain in torpor for much shorter periods. During warmer spells, black bears in torpor are more likely to stir and may emerge to forage, as perhaps was the case with this individual. All these important carnivores around, and no wonder! We have also been detecting a lot of ungulates, deer and elk, who make up important parts of the diets of coyotes, mountain lions, and black bears. An male elk with a thick reddish mane eyes the trail camera. The camera sites captured several large elk herds on the move, and it's a sight to see! But have you ever wondered how to tell if you're looking at an elk or a deer? This elk above exhibits the thick mane and hump on the shoulders that is common in elk and absent in deer. Compared to deer, adult elk are also significantly larger, the hair of their mane and legs is dark, they have a large white rump patch, and their tail is short and completely white. Top: A large herd of elk gather in a clearing. Bottom: An animated gif showing elk passing by in front of a camera. In Oregon, we have two subspecies of elk: Roosevelt and Rocky Mountain elk. We also have two species of deer, white-tail deer and mule deer, plus a subspecies of mule deer called black-tailed deer. White-tail deer have brown hair on the dorsal (top) surface of their tail, and mule deer have a white tail with a brown tip. The deer shown below are black-tail deer. You can tell where they get their name: the topside of their tails are covered with dark hair. All these deer also have white hair on the ventral (underside) of their tails - all the better to signal to the herd with! Left to right/Top to bottom: Two deer race through the snowy camera site clearing. Two deer stand nose to nose. Two deer walk through the snow. A young buck shows off his winter molt. Another buck approaches the camera. Snowshoe hare continue to be regular and welcome visitors to several camera sites. Left to right/Top to bottom: A snowshoe hare crouches in some underbrush. A snowshoe hare hops through a snowy camera site. A snowshoe hare bounds along a game trail. There were also many squirrel sightings, like these western gray squirrels: Left to right/Top to bottom: A western gray squirrel pauses on a log; bounds through the snow; pauses in a grassy clearing; sits upright amid snow patches; and streaks through a camera site. Did we go a month without a Douglas squirrel sighting...? Rest assured we did not! A Douglas squirrel pauses on a log, obscured by fog. Trackers also encountered a lot of squirrel and snowshoe hare tracks on transects! These common winter wildlife species both can have bounding trail patterns, and learning to tell the two apart can be tricky at first. Left/top: A snowshoe hare left all four paw prints in the snow. Right/bottom: A snowshoe hare trail in snow. Now, this is one classic snowshoe hare print above! Notice the "T" shape made the two larger hind paw prints side by side, and the two smaller circular front paws prints one after the other. The mismatched size of the prints made by larger hind paws and smaller forepaws is a good characteristic to look for in hare tracks (but squirrels tracks have this characteristic too!). See the series of "T"s as the hare hopped along? This rabbit's stride (the distance between two prints made by the same foot) was 23" in this picture. Now, compare this to squirrel tracks: Left/top: a cluster of a set of squirrel tracks in the snow. Right/bottom: A squirrel trail in the snow intersects with a trail of humans. In the close up of squirrel tracks above, we see larger hind paws positioned in front of smaller fore paws, as with the snowshoe hare, but it appeared as a cluster of four prints rather than a "T". Hare's front feet tend to leave a staggered "T" pattern, while the front feet of squirrels tend to land side by side. You can see this consistently play out in their trial pattern on the right/bottom above. Below is the first raccoon that cameras have detected this season. Raccoons remain active year-round. Like bears, they do not fully hibernate, but are less active during the winter. Here's a cropped photo with the exposure increased - that striped tail is a giveaway! A raccoon, barely visible, walks through some fallen logs. Our final visitor this past month was the striped skunk! A striped skunk strides off into the undergrowth. Like black bears and raccoons, these mammals are less active throughout the winter as they undergo hibernation torpor. Looks like these snowless conditions were still good rambling for this skunk.
Until next time, smell ya later! And be well. |
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