Bobcats are active all winter, particularly at dawn and dusk, when their primary prey (hares and cottontails) are active. Mice and voles are also a significant part of their diet, and occasionally larger-bodied male Bobcats successfully prey on White-tailed Deer. The pictured tracks reveal that while foraging for food, a Bobcat discovered the remains of a Porcupine that had been killed and skinned by a Fisher.
Whether or not North American River Otters made the original holes evident in Wednesday’s Mystery Photo, they were responsible for keeping them open by frequently poking their heads up through them for some air. Congratulations to Noel K. for being the first to correctly identify their surface holes. This was a tricky Mystery Photo, as there were none of the usual signs of otter activity (tracks, fish remains, etc.) on the ice surrounding the holes. This is probably because the ice was too thin to support the weight of an otter. To find the most humorous response, scroll down on Wednesday’s Mystery Photo comments until you get to Peg Emerson’s.
These semiaquatic members of the weasel family are active year-round and while they are mainly nocturnal and crepuscular during the summer, they are frequently spotted during the day in winter. If otters encounter open water, they rarely resist the urge to enter it and pursue resident fish.
Thanks to their webbed feet and streamlined body, otters are accomplished swimmers and divers. They are able to reach a depth of around five feet and remain submerged for up to four minutes as they hunt underwater. Top swimming speed is seven miles per hour. (They can achieve a speed of up to 18 miles per hour when running and sliding on snow or ice.) While fish are their mainstay, these carnivores also consume frogs, snakes, turtles, insects, birds and bird eggs and the occasional mammal (mainly muskrat). Though called “river” otters, they forage in fresh, salt and brackish waters. (Thanks to Rita and Dave Boynton for photo op.)
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American Martens (formerly Pine Martens) are making a comeback in northern New England. On New Hampshire’s Threatened Species List, and on Vermont’s Endangered Species List, American Martens are rebounding from the effects of habitat loss and trapping in the early 1900’s, but are still considered rare. This medium-sized member of the weasel family is slightly larger than a Mink and smaller than a Fisher, and often has a light orange bib, or throat/chest patch. Lighter fur usually is found on their head and along the edges of their ears. In addition to a pair of scent glands, which all weasels have, American Martens have a glandular area on their lower abdomen that exudes a musky-smelling, oily secretion used for scent marking.
American Martens spend a lot of time in trees. Their semi-retractable claws help them climb and hang onto branches. In addition, their hind limbs can be rotated at the ankle (like Gray Squirrels) to allow them to descend a tree very quickly, and their long, bushy tail helps them balance.
Because they store very little fat, martens must hunt every day. In the winter they are active for about four hours a day (14 hours/day in the summer), and during this time consume an average of three voles or the equivalent amount of chipmunks, birds or other small rodents. A sighting of an American Marten is a highly-prized experience. (Thanks to Laurie Stokes, whose photo of a Pine Marten was taken in the White Mountains of New Hampshire.)
After spending their first month or so underground in their den, red fox kits emerge and discover the great outdoors. This is the most carefree time of their lives – days are spent playing tag, “king of the mountain,” and “hide and seek.” Engaging in mock fights, pouncing on each other as well as on insects (learning how to capture their own food) and tumbling in the dirt are the norm. Food is delivered to them, coats are groomed and life is good.
Coyotes mate in January and February, but pre-mating behavior started two to three months ago. During this period scent marking increases, as does howling, and males wander far and wide. Female coyotes come into heat only once a year. When this happens, and two coyotes pair up, they may howl in a duet before mating. If there is an ample food supply, most females will breed and between 60% and 90% of adult females will produce a litter. The size of the litter fluctuates with the size of the rodent population; lots of rodents means larger litters. The same pair of coyotes may mate from year to year, but not necessarily for life. (Photo taken at Squam Lakes Natural Science Center)
Like many carnivores, coyotes do not have permanent homes, other than the maternal dens in which their young are raised. After being active at dawn and dusk (as well as occasionally during the day and night), they are apt to rest, curling up in beds they make in the snow right out in the open. However, they will take advantage of a sheltered spot, such as this hollow stump, if it presents itself. Tracks leading into and out of this stump, in addition to many hairs on the ground inside it, left no question as to what canine had sought shelter here from the cold, winter wind.
As these wet footprints and tail drag marks indicate, mink are excellent swimmers, and spend a great deal of time in all seasons foraging in and along streams and ponds. As a rule, all weasels can often be found close to water, as they drink often, though relatively little at a time. But mink do far more than drink water – they find much of their prey, including crayfish, frogs and fish, in it and are very well equipped to capture them. Mink can swim underwater to a depth of 18 feet and they can swim as far as 100 yards. Look for their tracks going in and out of openings in the ice that covers much of a stream’s surface this time of year.
Coyotes are opportunistic carnivores – whatever is available and relatively easy to find and/or catch, coyotes will eat. In spring, summer and fall, insects, small rodents and fruit make up most of their diet. In winter, when insects aren’t around and rodents are hidden by snow, coyotes are more dependent upon carrion, particularly white-tailed deer. Coyotes are often blamed for preying heavily on deer, and their scat often does contain deer hair, but studies have shown that most (92% in one study) of the deer consumed by coyotes are scavenged after being killed by vehicles or having died as a result of other injuries. A large percentage of the deer that are killed by coyotes have severe pre-existing injuries and would likely have died from them had they not been preyed upon by coyotes. (The pictured coyote scat consists largely of rotting apples, with a sprinkling of deer hair.)
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You can spend days following the tracks of a fisher – this tireless member of the weasel family travels up to ten miles a day during the winter, foraging for food and stopping to bed down periodically. One of the more common signs of fisher, other than tracks, is their resting spots. Fishers are active day and night, but even they have to stop now and then to rest, often at the base of a tree. More often than not they defecate before departing. If you look closely you’ll see the fisher’s scat – guide books often state that the scat of fishers is dark and twisted. While this is sometimes so, their scat can also be somewhat mustard-color and not be at all twisted, as in this photograph.
When looking for signs of weasel– Long-tailed or Ermine (formerly called Short-tailed Weasel) – in winter, stonewalls are a good place to head. Both of these nocturnal mustelids prey on small rodents such as mice and voles, which frequent the nooks and crannies of stonewalls. In winter weasels cover a lot of ground looking for prey – the home range of an Ermine is between 30 and 40 square acres, but when food is scarce, they may travel two or three miles in one night. Often their tracks will run the length of a stonewall on one side and then back the other side. Intermittent pauses are made as the Ermine stands on its hind feet and stretches its neck out, searching the landscape for both movement and sound.
Eastern Coyotes are heard with some regularity in New England, especially in the fall. The typical family unit consists of two parents and their young that have yet to disperse (often females). Together these four or five Coyotes serenade us with a very distinctive chorus, often several times a night. One wildlife biologist described this chorus as starting with a few falsetto yips, then blossoming into something resembling maniacal laughter, with the yips stringing together into chattering howls. Coyotes use their voices to communicate with members of their family, as well as with other Coyotes. If the family members have been off hunting by themselves, the howling serves to call the family back together again. The familial chorus also serves as a warning to other Coyotes not to trespass onto their territory. (Unless otherwise noted, my photographs are taken in the wild. This photograph was taken at Squam Lakes Science Center.)
Two species of weasels (smaller relatives of mink and otters) are found throughout New England – the long-tailed weasel (pictured) and the short-tailed weasel (also known as an ermine). Both are roughly the same size (somewhere between 9 and 16 inches), with long thin bodies and short legs. Visually telling these two species apart can be challenging unless you get a good look at both the tail and the body, and even then, it can be difficult. A short-tailed weasel’s tail is about 40% of the head and body length, whereas the long-tailed weasel’s tail is more than 45% of the head and body length. In the northeast, in November, both of these carnivores usually start shedding their brown summer coat for a white winter coat, and then molt and start growing in a brown coat again beginning in March. Further south, in Pennsylvania, less than half of the long-tailed weasels turn white, and none do south of the Pennsylvania/Maryland border. (Thanks to Tom Kennedy for photo op.)
A study of coyote prey (through stomach contents) in the Adirondack Mountains of New York revealed that beavers were second only to white-tailed deer. This photograph shows that, possibly for the last time this winter, a coyote recently took advantage of a still-frozen-but-fast-thawing pond by walking across it in an attempt to reach an active beaver lodge. Once there the coyote attempted to dig into it in order to reach the inhabitants. A hard, two-to three-foot-thick wall of frozen mud, logs and sticks kept the beavers well protected, as it was designed to.
Coyote tracks led to a hole dug in the snow, with the body of a shrew lying on top of the snow next to the hole. Apparently a coyote had succeeded in catching the prey it had heard, but upon smelling this tiny insectivore, the coyote decided it wasn’t that hungry. In addition to having poisonous saliva that immobilizes small prey, shrews possess two glands on their sides that emit an unpleasant odor, detectable even by human noses. Although this odor did discourage the coyote from eating the shrew, it wasn’t enough to save its life.
It’s often a lot easier to find signs of otters than otters themselves. Recently I discovered two dead crayfish on the shore of a mostly iced-over pond that I knew was inhabited by otters. Nearby otter scat confirmed that these crayfish were probably left by satiated otters. The most important prey item in a majority of otter scat analysis studies is fish, followed closely by crayfish. Otters will take advantage of other prey, such as frogs, salamanders, ducks, muskrats, an occasional young beaver, mice, snakes, insects and even turtles when readily obtainable, but fish and crayfish are first and second choices.
I have never heard of this particular fisher hunting technique, nor have I seen or read about it before, but there’s no denying that a fisher made these marks in the snow and that they tell the story of how it captured a mouse or vole. It’s likely that the fisher could hear or smell that the rodent tunnel in the subnivean layer was occupied. It looks as though the fisher methodically scraped snow towards the center of the circle, going completely around the tree in an attempt to trap and/or expose the mouse or vole within the circle. It succeeded in opening up the rodent tunnel (the hole is in the dead center of the photograph), and if the tiny droplets of blood on the snow near the hole are any indication, was successful in capturing its prey.
For the past two to three months, coyote courtship has been taking place. Both males and females have been marking more frequently, and male coyotes have been traveling further than usual in search of a mate. A female has marked the top of the stump in the photograph – you can see the foot prints she made as she squatted to urinate. The blood-tinged urine indicates that she is in estrus, or heat. With luck, you might hear the duet of a male and female coyote that is sometimes sung just prior to copulation.
Has your dog ever flopped down into the snow, rolled over and wiggled its body back and forth, appearing to rub its back? This behavior is exhibited by other members of the dog family, including coyotes. With a little imagination you can see the coyote’s head print at the left side of this impression, and its hind feet on the right, both made while it was “ottering” in the snow. If anyone can shed light on why canids engage in this winter time activity, it would be much appreciated!
Tracking has its rewards, and when you’re following a predator, one of them is to come upon a site where the predator captured prey. After snowshoeing up and down forested Vermont hills following fresh bobcat tracks, I decided that bobcats don’t always mark their territory as often as I had thought, for this bobcat had not paused, nor stopped to spray urine or defecate the entire time I followed it. Eventually, however, on top of a knoll, it sat down behind a tree. There were marks in the snow that indicated that it had gotten up and then leaped down the slope, sliding several feet when it landed and then pounced on a red squirrel. All that was left of this woodland high drama, in addition to bobcat tracks and blood, was a piece of the squirrel’s tail, some squirrel scat and part of the squirrel’s stomach. If you look carefully, you can see where the bobcat sat (bottom of photo) while it enjoyed its meal.
Although fishers are agile climbers, they catch most of their prey and do the vast majority of their traveling on the ground. Occasionally, often in coniferous forests or if threatened, they will climb a tree. When they decide to come down, they jump and land on all four feet. If there is snow on the ground, the fisher leaves an impression, the clarity of which is determined by the depth and relative dryness of the snow. In the wet snow we’ve had recently, a fisher’s four feet left clear tracks when it landed on the ground, and you can even see a slight depression where its head touched the snow. Sometimes the tail is also evident. In this photograph, you can tell the direction in which the fisher intended to head without even looking for further tracks, just from the angle of its body.
If you take a walk along a small wooded stream that has many fallen trees along its banks, you can expect to find mink tracks somewhere along it. These wetland-loving weasels dig their dens in river banks, often under tree roots, and judging from their tracks, visit them frequently. It is not unusual for one mink to have several dens which it uses as resting spots along a stream. Mink spend a lot of time in the water hunting for fish, aquatic insects and crayfish. Mink are good swimmers and can dive as deep as 16 feet. Tracks will run along the frozen sections of a stream, and then disappear into the water, only to reappear on the ice further downstream when the mink decides to travel on solid ground again.
Following tracks is a very rewarding past-time, as they often reveal an animal’s diet, interactions and survival strategies. Recently coyote tracks led me to the top of a knoll, where the coyote chose to bed down. A few remnant hairs and the circular shape of the indentation confirmed the identity of the animal I had been following. Coyotes and foxes tend to sleep with their heads wrapped around their legs and their tails covering their noses, leaving a circular indentation in the snow. Coyotes often choose to bed down in a spot that’s in the open or on top of a raised surface such as a small hummock (see photograph) or boulder, so that they can spot both prey and predators (primarily humans) in any direction.
There is nothing like heading out on snowshoes to look for tracks after a major snow storm has passed. The pristine snow is often untouched, except for a few brave souls who have ventured out. Most of the mammals that are active in winter hunker down until well after it has stopped snowing, but the mink (Mustela vison) is not about to lose a night of hunting and its tracks can often be found the morning following a storm. Like other weasels, this bounding carnivore often leaves diagonally paired tracks, but unlike other weasels, its tracks are consistently the same distance (1 to 3 feet) apart. They also are most prevalent in or near wetlands. Although a fierce predator, the mink also has a playful side, much like its cousin, the river otter. Mink are known to dive under the snow and make short tunnels. Even more delightful to come upon are the slides that mink often make down inclines. If you see a groove in the snow about 3” in diameter, with paired tracks at either end, you have come upon such a slide.