Cascadia Wildlife Blog
News from the Wolverine Tracking Project and more
The days are getting warmer and longer, the birds are returning from winter migration, and animals everywhere are bringing a new generation of wildlife into our forests...needless to say, winter has ceased and made way for spring, marking the end of our winter survey season. While this season may have been unexpectedly cut short, the Cascadia Wild team of volunteers and members still managed to bring in countless wonderful photos and record many wildlife tracks while it lasted.
Please enjoy this season recap of the Wolverine Tracking Project's Camera and Tracking Survey highlights!
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As we near the end of the winter season and head into spring, the snow begins to slowly melt away and our forests begin to wake up. With warmer weather comes breeding season, new growth of plants, and more abundant food sources for the wildlife. As insects take to the wing and feed our avian community returning from migration, we begin to notice a shift in the dynamics of the forest. We look forward to the spring ahead and enjoy looking back on February and the wildlife sightings it provided us. As always, thank you to all of our wonderful volunteers who are braving the winter weather on snowshoe and digging through the snow to reach our cameras so that we can bring you these photos. We have had a great season so far, and winter's not over yet! We still have a month of wildlife tracking and two months of camera surveys in Mt Hood National Forest to complete the winter wildlife survey season. For those of you excited to get outside, make the most of the snow while it lasts, welcome the transitioning seasons, or simply explore the natural world, we hope to see you at one of our upcoming classes or clubs! Upcoming classes and Clubs
Late winter/early spring is the perfect time to get to know our local songbirds, and our Bird Language Series is a great opportunity to do so! Beyond bird identification, this 8-class series in field and classroom explores what the postures, song, chatter, and even silence of birds can tell us about what's happening on the landscape - the location of predators, presence of other humans, and even our own awareness and mindset. Starting March 22. Read more. Check out our other upcoming classes, like Advanced Sign Tracking (March 7) Intro to Wildlife Tracking at Hoyt Arboretum (March 21) and more! See all upcoming Classes. Looking for more to do in the community? Tracking Club meets the last Sunday of every month. Nature Book Club meets March 24 to discuss Rain: A Natural and Cultural History by Cynthia Barnett. More info on Community Clubs camera surveysThere has been an abundance of wildlife sightings on Mt. Hood this past month, including our beautiful and elusive target species: the Sierra Nevada red fox! A Sierra Nevada red fox observes the area and looks into a nearby camera The Sierra Nevada red fox was first confirmed on Mt. Hood in 2012 by Cascadia Wild's trail cameras under the Wolverine Tracking Project. Despite their small numbers, attempts to list these animals as threatened or endangered have failed in recent years due to the lack of information on their populations and whether or not they are interbreeding with other red fox subspecies. Cascadia Wild uses data collected on this subspecies to aid researchers and conservationists in their attempt to protect the Sierra Nevada red fox. Due to their elusive nature, there are many questions left to be answered, such as their population sizes, distribution, genetics, and ecology. Data is gathered by Cascadia Wild through our camera surveys, winter tracking surveys, and summer scat surveys. A Sierra Nevada red fox examines the camera site and bait tree These foxes are always an exciting find, and they have graced our higher-elevation cameras a handful of times this season. Their curiosity of the bait trees are hard to misinterpret, and the body language they exhibit is not unlike that of our canine companions. Some fun facts...
Other canid visitors include the coyote. A coyote strolls through a camera site in the fresh snow Coyotes are generally monogamous and tend to maintain pair bonds for life. Their litters are raised by both parents and parenting duties are also frequently taken on by older siblings in the family group. They travel both alone and in packs usually consisting of an alpha male and female, their relatives, and some members of other families. Coyote packs tend to live in territories that they will defend against neighboring packs. They mark these these territories with scent markings such as urine, feces, and rubbing against objects like trees. Left to right (mobile: top to bottom): a coyote marks its territory with feces; the territory is observed by scent; a coyote marks its territory with urine; two coyotes mark their presence by rubbing up against a tree trunk. There is some evidence that suggests individual coyotes mark their territory more frequently when they are traveling with a pack! This group of 5 is seen claiming their stakes on the land. A pack of coyotes roll on the ground and smell the surrounding area A coyote examines the camera site Some fun facts...
Other carnivorous mammals caught on our cameras this past month include the stealthy bobcat. A bobcat sits underneath a tree Bobcats have a wide range of diet, including small mammals such as hares, squirrels, birds, and even the occasional larger game like deer. Bobcats use their stealth to hunt, remaining hidden to their prey until they attack with a leaping pounce of up to 10 feet. A bobcat sneaks through the camera site at night These felines are the most common wildcat in the United States, yet they seldom cross paths with humans due to their solitary, nocturnal, and elusive nature. A common meal of the above carnivores are the snowshoe hares. Multiple snowshoe hares make their way through our camera sites Snowshoe hares have evolved to molt to a white coat for the winter to match the snowy backdrop, and molt back to brown once the snow melts away; this way, they do not stand out like little lightbulbs in the dark forest, and they are able to camouflage with their environment year-round. However, as demonstrated above, sometimes these color changes do not happen as they should. As the global climate changes, the presence or absence of snow at different times of the year becomes less predictable, and hares are sometimes unable to quickly change their coat to match - a phenomenon biologists call "camouflage mismatch". Abundant in our forests, the snowshoe hares are nimble and fast; a necessary advantage as a favorite snack of bobcats, coyotes, foxes, and even some birds of prey. These hares have large, fuzzy feet that help them to effectively navigate their snowy habitats, similar to the snowshoes of our volunteers. Other herbivorous inhabitants of our forests include the black-tailed deer. Left to right (mobile: top to bottom): a deer jumps over some fallen logs; an up-close shot of a deer walking underneath the camera; a deer walking up close to a camera. Black-tailed deer inhabit the forested mountains and foothills near the Pacific coast. They are resident animals, meaning they do not migrate south, but do tend to move to lower elevations during the winter months. Their home-range consists of about 3 square miles of land, yet they tend to travel in solitude - aside from the small family groups of mothers and their young, or the bachelor groups of bucks formed during the summer months. You can find more information about deer in our last blog. A female black-tailed deer exhibits a flehmen response A flehmen response is a reaction to intriguing smells - commonly urine - where the upper lip of the animal is curled back to expose the vomeronasal organ to the scent in order to get a good whif. In fact, the word "flehmen" comes from the German verb for "to curl". However, this response is not just "sniffing" - it may be compared to sniffing in high resolution. This black-tailed deer doe is seen exhibiting a flehmen response, likely in response to the urine of another deer. You may have observed a cat or another ungulate like a horse displaying this same behavior before. While not uncommon, a flehmen response is more frequent in black-tailed deer males than females. In fact, there seems to be an annual cycle for flehmen responses in black-tailed deer; observations are much more frequent in the winter during breeding season as deer are on the lookout for a mate. Also seen is a less common winter visitor: a striped skunk. A striped skunk runs through a clearing, leaving behind small tracks in the snow Striped skunks tend to hole up for the winter; however, similar to bears, they do not undergo true hibernation. Instead, both skunks and bears exhibit something called torpor: a state of decreased metabolic and physiological activity, allowing an animal to survive through periods of food shortages. More information on torpor can be found in our last blog. Though skunks tend to be known for their foul smelling spray, they are actually docile animals that will happily leave humans alone and go on with their day. Their spray defense is typically only used as a last resort; if they feel threatened, they will first try to run away from the threat. If that doesn't do the trick, they may arch their back and raise their tail as a warning. Only if they still feel threatened will they release their spray, which can reach a whopping 12 feet. Tracking SurveysBefore we review some of the findings from our tracking surveys, we want to extend our congratulations to our trackers, tracking trip leaders, and greater tracking community that came out for our CyberTracker Track and Sign Evaluation! For two days, participants were taken to various locations in Mt Hood National Forest and asked questions about the track and sign found on the landscape, such as: who made this track or sign? how was this animal moving? what was the gender of this animal? At the end of the weekend, everyone who participated received internationally recognized wildlife tracking certification! Six out of ten participants even received Level 3 Certification! Thank you to David Moskowitz for leading the evaluation on behalf of CyberTracker, and everyone who came out to share their knowledge, perspectives, and tracking skills with us - we are truly impressed by our community! We found a lot of great tracks and sign, and here are some of the highlights from the course: Left to right/Top to bottom: the class discusses track morphologies; following one of many snowshoe hare trail; the tracks of a male bobcat show clearly on a light dusting of snow and dark substrate; tracks of two deer crossing a road; a set of clear weasel tracks found near a bobcat trail; David discussing a mound created by a mountain lion; a trail sign post that has been used more than once by black bear for rubbing; and a vine maple branch that has been browsed upon by deer. It's been a great month for our tracking surveys, too! This February we hosted our annual overnight tracking trip in the Tilly Jane area. Left to right/Top to bottom: sizing up a snow shelter footprint; looking out from a snow shelter entrance; and the long shadows of sunset on a burn area fall onto a snowy field with Mt Hood in the background. The group followed animal trails by day before setting up snow shelters and camping under the clear skies of a full moon. The conditions for a great time could not have been better! Tracking surveys have also been finding a lot of great track and sign. One of the most common signs on the winter landscape is snowshoe hare. A snowshoe hare crossroads with ample scat A print of a snowshoe hare sitting: the small front feet are in front (on the left), hugged by the large hind feet, and an imprint of the round tail sits behind (on the right) - under the tail print is a rabbit pellet, or scat! A snow "cave" is made by snow on a sapling: the tracks here show the frequent comings and goings of snowshoe hare to this site. The amount of packed snow at the entrance of the "cave," the stipped branches, and the pile of needles indicate that a hare used this area for feeding if not also rest and hiding. Hare tracks were found entering this snow tunnel! Trackers searched the area and found another set of tracks exiting the snow some distance away! We have also been finding a lot of squirrel tracks, and the similar tracks of their carnivorous forest counterpart, weasel! Can you tell the difference between squirrel and weasel in the tracks below? Left to right/Top to bottom: measuring the clear prints of a short-tailed weasel; the bounding gait of a weasel through snow; a tracker inspects the bounding gait of a squirrel through deep snow; and measuring the tracks of a squirrel. In our last blog, we discussed how squirrel and hare tracks can be distinguished from one another, but weasel and squirrel can be even more difficult to tough to tell apart. Also commonly found with a bounding gait, weasel tracks can be of similar size, too. One way to tell these apart is by the toes. Squirrels have five toes on their hind feet and four in front; weasels have five toes all around. Squirrels will also have longer toes than claws (for grabbing onto food and tree limbs) and weasels will have longer claws than toes (for grabbing onto their forest prey). Compared to weasels, the first and fifth digit of a squirrel's hind toes are splayed more to the side, while the middle three are kept closer together and pointed more forward, in a 1-3-1 orientation. Weasel toes, on the other hand, will often be more evenly spaced. Another common track has been the deer mouse. These tracks would be difficult to discern if not for their size! Some of the smallest tracks in the forest, you would be very lucky with excellent conditions if you were able to make out toes in their prints. Left to right/Top to bottom: a deer mouse bounds through crusty snow; and a deer mouse bounds through a thinner layer of fluffier snow. Each of these photos show the same animal performing the same hopping gait. However, the animal is making its way through two different qualities of snow. The first photo shows each foot clearly defined as the animal almost post-holes through snow that has been made more rigid through melting and refreezing, each foot clearly showing where it broke through the surface. In the second photo, we can see the tracks less clearly as the snow hasn't gone through the same weather and is more easily disturbed, yet still light and fluffy enough to pick up a foot drag. We have also seen a lot of sign from our forest carnivores. One thing all our wildlife have in common is: what goes in, must come out! Left to right/Top to bottom: canid scat (coyote or fox); felid scat (bobcat or small mountain lion); likely coyote scat containing ungulate fur. Scat can tell us so much about an animal, from genetic information, to diet and individual health - all of which in turn helps us paint a picture not only of their population but of the ecosystem to which the animal belongs. The top two photos belong to two different families of animals, canid and felid. Comparing the two, you can see that canid scat is a bit more twisty than felid scat, which comes out more round and segmented, like Lincoln Logs. Both have bits of hair, which attest to their more carnivorous diet. The bottom photo is likely coyote scat, and contains what is likely ungulate fur. Examination of the fur showed that it crimped when pinched between the nails, indicating a hollow hair follicle. Ungulates and polar bears are the only mammals with hollow fur, an adaptation which helps them stay insulated in the cold. Until next time, we hope you can get out there and enjoy some of the bounty that winter has to offer before it's gone!
Winter is in full-swing, January brought us deep snows and lots of photos from the Wolverine Tracking Project, and looking ahead, February is shaping up to be a busy month with March not far behind! See below for news on our camera and tracking surveys. But first, check out some of the classes and events on the calendar. Upcoming classes & events
As always, Tracking Club meets the last Sunday of every month. Nature Book Club meets Feb 25 to discuss Reading the Forested Landscape by Tom Wessels. More info on Clubs Camera SurveysA big thank you to our volunteers who have been braving the elements to maintain our camera sites! All the fresh snows on Mt Hood have given our camera crews a lot of opportunity for snowshoeing, digging cameras out of the snow, and bringing back some great photos! We've captured a few winter photos like this (below): A snow-covered camera takes a programmed, daily photo However, thanks to our volunteers braving the elements, we have also detected a lot of wildlife. When the heavy snows weren't burying our cameras, which were originally installed about five and a half feet up a tree, they were making some cameras appear to be at ground level. The result? These wonderful close-ups: A Pacific marten inspects a camera, leaving behind footprints in the freshly fallen snow It is always exciting to see a Pacific marten, especially so intimately. We love that we can also see such clear tracks as it departs, too. Note the elongated foot pad of its back feet, circled by five toes. This print is characteristic of mustelids, the family which Pacific marten, wolverine, fisher, mink, weasel, and so on belong. A little about marten...
Snow-level cameras also detected some other animals, which make up our marten's carnivorous diet: A deer mouse leaves a trail (left/top) and a snowshoe hare comes for a visit (right/bottom). The fresh tracks of the deer mouse show it's hopping gait - though much smaller, it is very similar to the trail a snowshoe hare would leave: small front feet landing first and the larger, more powerful hind feet landing second just ahead of the front feet. We also detected an up-close and candid portrait of another target species: the Sierra Nevada red fox! A Sierra Nevada red fox makes its way through deep snow Again, you can see the tracks of this montane fox in the snow. With a meandering trail like this and nose to the ground, it's not hard to assume this fox is hunting. Rodents often burrow into the snow, using the insulating layer as protection from predators and the cold. Foxes at three different sites inspect the bait trees (top row and bottom left). A video shows multiple visits of what appears to the be the same fox to one site over a period of three weeks (bottom right). These many visits from these rare, native foxes help us understand their habitat use. We have also collected a few viable hair samples from some of these sites. Like scat samples, hair samples may help give us important genetic information to help us understand their population history, genetic diversity, and habitat connectivity. Hair samples are collected on wire brushes, which are attached to the black belt on the tree just under the bait. Our region is home to three kinds of montane fox, the Sierra Nevada red fox (Vulpes vulpes necator) in the Oregon Cascades and Sierras, the Cascade red fox (V.v. cascadensis) found in the Cascades north of the Columbia River, and the Rocky Mountain red fox (V.v. macroura) who are native to northeast Oregon. And, just this week, it was announced that there is a population of Rocky Mountain red fox living near Bend, and likely has been in this area for some time! Just like the Sierra Nevada red fox in our backyard, the montane fox can be elusive and difficult to study, even when they are right under our nose. Other recent visitors include the ever-present coyote. Left to right (mobile: top to bottom): a coyote fixates on a tree; two coyotes look on while a third rolls in fresh snow; a coyote with a white-tipped tail pauses, then leaps over a log to smell a stump; and finally, a coyote stands chest-deep in the snow, likely listening for rodents. Though the final coyote's retreat was not captured, its tracks show it departed the way it came, taking the time to circle (and likely mark) the stump behind it (final photo). We've also detected a few bobcat: Left to right (mobile: top to bottom): a bobcat walks past a bait tree; bobcat walks down a game trail; bobcat inspects a bait tree; bobcat leaves tracks in fresh snow; bobcat smells the base of a bait tree; and a bobcat passes through a site with what looks like a freshly caught hare The bobcat on the right (or bottom), is difficult to make out. However, this lucky visitor is sporting a freshly caught hare! Bobcats (Lynx rufus) are well-adapted for snowy mountains, and, like foxes, marten, and coyotes, snowshoe hare are a favorite snack. Bobcats often hunt at night, and like the marten, don't let their small size fool you! They can cover 10 feet of ground in one pounce. We are more likely to see bobcats on the mountain in the winter than their felid cousin, mountain lion. Mountain lions (Puma concolor) are less adapted to snowy environments than bobcat and are more often detected at lower elevations than where most of our cameras are located. Another visitor we don't expect to see in the winter? Black bear. However, our cameras did pick up a bear between snows, a bit later than we would expect to see one. A black bear walks down a game trail between winter snows Bears do not hibernate in the same way as most other animals, like some rodents and reptiles, who lower their body temperature along with their metabolism and sleep throughout the whole winter. Instead, they enter a state called torpor where their metabolism slows down, but their body temperature remains elevated and they are able to wake more easily. They can wake from this sleep-state during winter if the weather warms or they are disturbed, and they may even leave their dens, eating opportunistically if they come across food, but do not tend to venture out for long. Other animals that enter a similar torpor state are raccoons and skunks - plenty of reasons why it is always good to be aware of your surroundings in the forest! Whether this particular bear is taking a mid-torpor stroll or has yet to enter this state for the winter is hard to say. One animal, we are not surprised (but always happy) to see is the black-tailed deer. Left to right (mobile: top to bottom): A doe in the snow; a buck in the snow; three deer in the snow; a buck on a game trail Did you know Oregon is home to four native subspecies of deer? Mt Hood National Forest is home to the Columbian black-tailed deer (Odocoileus hemionus columbianus), a subspecies of mule deer. These deer are found from the coastal ranges to the Cascades, and their range runs from California to northern British Columbia (a sister subspecies, Sitka black-tailed deer, is found in Alaska). Rocky Mountain mule deer (O.h. hemionus), another mule deer subspecies, are also native to Oregon, and they are found on the east side of the Cascades summits, most commonly on the east side of our state - fittingly, their range also includes both the American and Canadian Rockies. Black-tailed deer are a little smaller and darker than mule deer, but both have large, mule-like ears. While mule deer seem to prefer open steppe, black-tailed deer tend to prefer brushy areas of coniferous and mixed-coniferous forests, sticking close to clear cuts and burns for browsing opportunities. Oregon is also home to two subspecies of white-tailed deer: the Columbian white-tailed deer (Odocoileus virginianus leucurus) and the Northwest (Idaho) white-tailed deer (O.v. ochrourus). The Columbian white-tailed deer is the most rare deer in Oregon. They only live along the lower Columbia River and Umpqua Basin, and the Columbia River population is a federally protected endangered species. The Northwest white-tailed deer is found in the northeastern corner of our state and has a healthy population. As a species, white-tailed deer grow increasingly more abundant as you move toward the east coast. They can be found from Canada to South America and prefer mixed-deciduous forest types. In our area, you are most likely to see Columbian black-tailed deer - or if you are lucky, the rare Columbian white-tailed deer. Columbian white-tails have long tails they keep held closely to their bodies, and black-tails have shorter tails held loosely to their bodies. If you head a bit further east, you may see the Northwest white-tails; these are the smallest deer of all and have very wide tails. The antlers of each species are different, too. If the antlers are fully developed, white-tailed deer have one main beam on each antler, with points coming of the main beam; black-tailed deer (and mule deer) will typically have a fork coming off the main beam, with points coming off each branch. Check out ODFW's site to read more about our native deer or watch a video on Columbian black- and white-tailed deer identification. Almost as copious as deer and as perennial as coyote, are our forest corvids. Left to right (mobile: top to bottom): Clark's nutcracker; Canada jay; and a video compilation of the two species visiting the same tree over two weeks - almost every 1-2 frames is a new visit. Tracking surveysPlentiful snows, hearty trackers, and some luck have resulted in some great tracking surveys! One tracking team encountered three separate bobcat trails: Detail of bobcat tracks; another bobcat's trail The track quality on these tracks is great, even with a dusting of snow falling after they were laid. These photos show nice clarity of both the individual tracks and the trail pattern, and you can easily see the characteristic felid shape in these tracks. Compared to canid tracks, the whole of the print is quite circular and the thick, oblong pad is surrounded by four evenly spaced "toe beans." When distinguishing between dog and cat tracks, it's better to pay attention to these characteristics, rather than the presence or lack of claws: while felid claws are retractable (and canids are not), a bobcat or mountain lion can extend its claws for traction - something you may see on, say, a snowy/muddy/icy mountainside. Distinguishing bobcat from mountain lion is easy, at least for the adults of the two species: go by size! Under 2.25" diameter is likely bobcat; greater than 2.75" is likely mountain lion. The two tracks we are seeing the most of are snowshoe hare... Left to right (mobile: top to bottom): the meandering path of a snowshoe hare; older tracks show the commonly seen track pattern of undefined, large hind feet ahead of the small front feet; a tracking team examines a snowshoe hare trail along a log; detail of exceptionally clear hare tracks. ...and squirrel: Similar to the snowshoe hare, the older squirrel tracks show the commonly seen track pattern of undefined, large hind feet ahead of the small front feet; detail of clear squirrel tracks. The abundance of hare and squirrel is great news for the bobcat, whose tracks were found above, and the rest of our forest carnivores. The photos above show how similar these two animal's tracks are, both animals having bodies well-suited for bounding along, close to the ground. They can be difficult to discern from one another, but hare will be larger than a squirrel, and hare's tracks often have less definition due to the impressive amount of fur covering their pads and toes. Squirrel tracks are also more uniform and boxy - note how well the feet line up on the bottom set of squirrel photos, compared to the more staggered landing of the hare's front feet. In our forest, we have two kinds of non-hibernating squirrels: the Northern flying squirrel and the Douglas squirrel. However, it is difficult to tell their tracks apart. One way to tell? If you can follow the trail to the start, there will be a "landing strip" where the flying squirrel hit the ground. If you have clear enough tracks, you may be able to tell that the 5th toe on the hind foot (the "pinky toe") is almost as long as any other toe - that's a flying squirrel, too. Read more squirrel track analysis by David Moskowitz. Whether in town or on the mountain, we hope to see you soon!
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