An online resource based on the award-winning nature guide

Black Bears

Black Bear Dens

2-25-15 bear dens1Black bears den in a range of locations, including under logs and stumps, under the branches of a fallen tree, and inside caves and hollow trees. Most adult black bears are not completely protected from the elements while they are hibernating and/or raising cubs, as there is usually a fairly large opening and the bear is exposed to the cold air. The amount of exposure can vary tremendously, from a relatively protected hollow under a log to complete exposure within a dense thicket or stand of conifers. Pictured are two black bear dens where cubs were raised; one is under a fallen tree and the other is in the middle of a stand of spruces.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Black Bears Giving Birth

1-9-14  black bear cubIMG_0391Sometime between the end of January (the full moon in January is often called the ‘bear moon’) and the first part of February black bears give birth to between one and five (usually two) tiny, blind, almost hairless one-half pound cubs, each about the size of a chipmunk. The cubs are totally dependent on their mother for food and warmth.

Most dens are exposed to the cold air, as they are located under fallen logs and brush, or are dug into a bank. Occasionally they are on the ground with little or no cover; in all of these locations, the mother acts like a furnace, enveloping her young and breathing on them to keep them warm. The cubs do not hibernate, but nap frequently. Like human mothers, black bear mothers sleep when their young sleep, and are alert when their cubs cry and let them know that they are in need of attention. (Photo taken during NH Fish & Game/Ben Kilham spring research; cub in photo is two months old)


A Bobcat’s White-tailed Deer Cache

1-21-15  bobcat2 cache by Otto Wurzburg 009 (3)Rabbits and hares comprise much of a Bobcat’s diet, but when prey is scarce or hard to capture, adult male or sometimes large adult female Bobcats will attack bedded, weak or injured adult White-tailed Deer. Bobcats often cache prey (such as a deer) that is too large to eat in one feeding, returning to feed on it for an extended period of time. They scrape up leaves, bark, twigs, soil. snow – whatever is available – and cover their prey. When feeding on a deer, Bobcats bite away the hair to avoid eating it, and this discarded hair is frequently mixed with the debris that the cat drags over the kill to cover it (see main photo – taken the day after the deer was cached), or is left windblown around the carcass. A characteristic sign of Bobcat feeding is the amount of hair strewn around the carcass and the lack of broken long bones (Bobcats don’t have the strength to break them with their teeth).

Typically a Bobcat rests near its cache to protect it, but it doesn’t take long for other animals to detect and take advantage of an easy meal. Within three days of this deer being cached, Coyotes and Common Ravens had discovered it, and both they and the Bobcat had eaten enough of it to expose the deer’s rib cage (see insert).

Other predators that occasionally cache and cover their kills include Mountain Lions, Black Bears and Fishers. Large caches found in the winter in the Northeast are likely to belong to a Bobcat or Fisher (Fishers typically cache and feed on deer that they find as carrion).

(Cache discovered by Lynn & Otto Wurzburg, who observed the Bobcat leaving after caching the deer; photograph by Lynn Wurzburg)

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Black Bears Still Active

12-15-14  bear track in snow 049A7902While some, perhaps most, black bears have entered hibernation in northern New England by now, there are still some active individuals, probably males, who are finding enough food to delay denning. Typically a scarcity of food and cold weather trigger the reduction in the metabolism of a black bear, which signals the onset of hibernation. If the weather remains relatively warm and/or there is a large supply of beechnuts and/or acorns, signs of bears can occasionally be found even this late in the year. While there have been a few years when black bears have been sighted throughout the winter, most wildlife biologists say that it is safe to put up bird feeders in December, as sunflower seed-loving bears have usually retreated to their den sites by now. The pictured tracks and scat discovered in the past few days in central Vermont challenges that assumption (as does the stolen bird feeder). (Thanks to Erin Donahue and Charlie Berger for photo op – sensitive fern fertile frond for size comparison)

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Black Bear Scats Reveal Diet

8-25-14  black bear blueberry scat 062Black Bears are eating heavily now, in preparation for the coming winter when they will not eat or drink for several months. Some of what goes in must come out, however, and it can tell you a lot about the diet of an animal. Black bear scats typically weigh ½ to 1 pound or more. They have different shapes and consistencies, depending on what the bear has eaten. Black bear scats may be tubular or loose, depending on the amount of moisture in the food that the bear ate. Scat from succulent vegetation or berries is typically loose. Interestingly, black bear scats do not have an unpleasant smell if the bears ate only fruit, nuts, acorns, or vegetation — they smell like a slightly fermented version of whatever the bear ate.

At this time of year, Blackberries, Wild Sarsaparilla fruit and Blueberries are ripe and favored by bears. You can determine what a bear has been eating by the shape and size of the seeds in its scat. (A bear’s scat can consist of just one type of fruit if there is an ample supply of that fruit.) Wild Sarsaparilla seeds are crescent shaped, Blueberry seeds are tiny and sand-like, and Blackberry seeds are larger than Blueberry seeds. Blueberry scat (pictured) usually includes whole berries that were not soft and ripe enough to be broken up in the bear’s stomach. Bears hardly stop to chew berries. Instead, they swallow them whole and let the muscular, gizzard-like section of their stomach grind the pulp off the seeds. (Thanks to Jeannie Killam for photo op.)

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Hungry Black Bears

4-25-14 black bear IMG_3624When Black Bears emerge from their dens in the spring, they have lost between 15 and 40 percent of their weight, and food is in short supply. About 85% of a bear’s diet is vegetation, and most trees and shrubs have not leafed out yet. Black Bears often head to wetlands, where grasses and sedges are beginning to sprout. Nutritionally the shoots of these plants provide them with some of the protein they need, but this source of nutrients is short-lived, as the shoots are tender for only a few days before hardening with cellulose. Roots, bulbs, corms and tubers of plants such as Skunk Cabbage and Jack-in-the-Pulpit are sought after, as are the buds of trees, but bears must wait for the bountiful supply of berries and nuts that mature in summer and fall. Those bears living near humans come to rely on foods inadvertently provided by these humans, such as highly nutritional sunflower seeds being fed to birds. One can hardly blame bears for taking advantage of this available source of food during this challenging time. Feeders and cans containing seed should be put in a bear-proof location if you don’t want to encourage “nuisance” bears which, unfortunately, are sometimes killed just for trying not to starve to death.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Black Bears Birthing

1-27-14 black bear cubs IMG_0391Right now, partially or fully exposed to the sub-zero temperatures we’re experiencing, female Black Bears are giving birth to cubs that are blind, nearly hairless and weigh less than a pound. Although the mother’s metabolism is slightly reduced, her body temperature is relatively high, and she is very responsive to her cubs. The cubs do not hibernate – they retain full metabolism in order to maintain maximum growth, nursing frequently and for long periods of time. Their mother keeps them warm by hovering over them and breathing on them. Like human mothers, she sleeps when her cubs sleep, but awakens quickly and responds to their cries. (Photo taken during research; cub is roughly two months old.)

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Follow

Get every new post delivered to your Inbox.

Join 3,212 other followers