|
|
Post by Gorilla king on Jul 10, 2021 11:43:01 GMT -5
The American black bear Ursus americanus is the smallest and the most widespread bear species found in North America. Its ancestors are believed to have crossed into North America over the Bering Land Bridge about 500,000 years ago.
HABITAT
In Canada, black bears still inhabit 85 percent of their historic range from Northern Alaska to the east coast. They then become more and more dispersed across the United States as you go farther south. They are known to inhabit at least 40 of the states and can be found as far south as the Sierra Madre Mountains in Mexico.
Black bears are very adaptive and can be found in a variety of environments, though they prefer heavily forested areas. In the east, they are found primarily in forests and swamps. In the west, they are found mostly in forests and wooded mountains. Rarely are they found at altitudes any higher than 7,000 feet. Black bears are very solitary animals and are territorial. A male bear's territory is anywhere from 8 to 15 square miles and is about twice that of a female's.
CHARACTERISTICS
Most black bears are black with a light brown muzzle and often have a white V-shaped fur patch on their chest. However, many subspecies can also be found in other colors, such as the cinnamon bear in reddish brown, the kermode bear in creamy white, or the glacier bear in gray blue. They have small eyes and their ears are rounded and erect. Their claws which are shorter, sharper and more curved than the average bears are well designed for digging and climbing trees.
On average, adult black bears stand from 35 to 40 inches high and from 54 to 72 inches in length (tip of nose to end of tail). Their weight can range anywhere from 125 to over 600 pounds. Size and weight can vary to the extreme depending on food availability. Male black bears (boars) are usually 30 to 40 percent larger than females (sows). The largest black bear officially on record was shot in North Carolina in November of 1998, weighing 880 pounds. In December of 1921, a black bear reportedly weighing 900 pounds was killed in Arizona, but the report was unsubstantiated. Black bears in captivity may weigh even more being that they have a steady diet.
DIET
Like most bears, the American black bear is considered omnivorous feeding both on vegetation and animals. Most of its diet consists of vegetation such as nuts, roots, fruit, insects, honey, and bee larvae. It is capable of killing animals as large as an adult elk, though the animals that the black bear feeds on are usually limited to fish, small rodents, and carrion.
BREEDING
Females become sexually mature at 3 to 5 years, and males at 4 to 6 years. Mating usually occurs in May or June. Bears at more northern climates, however, might wait until July or August. After being fertilized, the egg freely floats inside the female's uterus for about 6 months before beginning to develop. Then after another 2 months, in January or February, the mother gives birth to usually 2 cubs. When born, the cubs usually weigh between 8 and 12 ounces. They are blind, hairless, and can't walk until they are 4 or 5 weeks old. At 6 months, they weigh from 55 to 65 pounds. They will usually stay with their mother for their first 1 to 2 years.
STATUS
It is estimated that there are between 767,000 to 914,000 black bears in North America and over 450,000 in the United States alone. They have no serious enemies other than humans. Over 90% of black bear deaths after the age of 18 months are the result of hunting, trapping, motor vehicle accidents, or other interactions with humans. They have lived to be over 35 years in captivity. However, the average life expectancy in the wild is 15 to 20 years.
www.bearsoftheworld.net/american_black_bears.asp
|
|
|
|
Post by Gorilla king on Jul 10, 2021 17:50:00 GMT -5
WEIGHTS OF ADULT BLACK BEARS:
WEIGHTS IN RELATION TO AGE:
|
|
|
|
Post by Gorilla king on Jul 10, 2021 17:58:40 GMT -5
The American black bear is the smallest of the three bears species found in North America and is found only in North America.
Black bears have short, non-retractable claws that give them an excellent tree-climbing ability.
Black bear fur is usually a uniform color except for a brown muzzle and light markings that sometimes appear on their chests. Eastern populations are usually black in color while western populations often show brown, cinnamon, and blond coloration in addition to black. Black bears with white-bluish fur are known as Kermode (glacier) bears and these unique color phases are only found in coastal British Columbia, Canada.
Defenders' Impact
Defenders of Wildlife is a leading advocate for black bear recovery.
Thanks to conservation efforts by the state of Florida, Defenders of Wildlife and others, the Florida black bear was removed from the Florida state threatened species list on August 24, 2012. We work with the Florida Fish and Wildlife Conservation Commission on developing long-term plans for managing and connecting bear habitat throughout the state and reducing bear mortality on roads.
We have also provided a variety of coexistence programs and resources, such as bear-resistant dumpsters, to help prevent human-bear conflicts.
defenders.org/wildlife/black-bear
|
|
|
|
Post by Gorilla king on Jul 10, 2021 18:08:49 GMT -5
|
|
|
|
Post by Gorilla king on Jul 10, 2021 18:15:38 GMT -5
American Black Bear ( Ursus americanus )
... Black bears, in general, are forest obligates that require the dense cover and diversity of food resources that diverse, healthy forests provide (Pelton 2003). Black bear activity revolves primarily around the search for food, water, cover, and potential mates (Pelton 2003). Food quantity and quality are perhaps the most important drivers of black bear demographics and activity. ...
Although classified as carnivores, black bears are best described as opportunistic omnivores because they eat almost anything that is available, including vegetation, berries, insects, and nuts that naturally occur in forests and other productive ecosystems (Pelton 2003). ...
.. American black bears are widely distributed and their historic range was once all of the forested regions of North America, including much of New Jersey (Hall 1981). Habitat destruction and predator control programs led to their extirpation in many areas (Hall 1981;Pelton 1982). Currently, black bears are found across Canada, the United States, and into Mexico, although in mostly localized populations. ...
.. Increased mechanical advantage of the jaw closing muscles may not be selected for in carnivorous bears because large bite forces are probably not necessary to take the small, vulnerable prey they prefer. Rather than serving as a predatory adaptation, high mechanical advantage of the jaw musculature in omnivorous bears may have been selected to process more efficiently the grasses and other fibrous vegetation that make up a substantial part of their diets (Pelton, 1993;Reid, 1993;Servheen, 1993;Weinhardt, 1993). ...
... In black bears (Ursus americanus), adult females establish territories during the summer, but otherwise home ranges overlap between and within sexes. Temporal spacing is exhibited by individuals, and likely maintained through a dominance hierarchy system (Pelton 1982). Similariy, raccoons (Procvon lotor) frequently have overlapping home ranges within and between sexes, with some evidence of temporal spacing and mutual avoidance. ...
www.researchgate.net/publication/346908248_American_Black_Bear_Ursus_americanus
|
|
|
|
Post by Gorilla king on Jul 10, 2021 18:43:31 GMT -5
|
|
|
|
Post by Gorilla king on Jul 15, 2021 12:21:02 GMT -5
|
|
|
|
Post by tyrannosaurs on Aug 3, 2021 3:53:30 GMT -5
Have Black and Grizzly Bears Become More Dangerous? Insights From Human-Bear Fatality Trends: References (22) Figures (2) Abstract and Figures Since 1900, black bears (Ursus americanus) and grizzly-brown bears (U. arctos) in North America have killed nearly 150 people, and injured many more. Rising fatality rate per decade has been speculatively attributed to (a) bears becoming more dangerous, (b) more bears encountering people, and (c) more people encountering bears. Although our focus was on the first hypothesis, testing it required addressing all three. To supplement our field studies on human-bear interactions, we analyzed temporal trends in bear attacks-data obtained by literature search-updating and extending studies by Herrero, Smith and their colleagues. We demonstrated that the rise in human fatalities per decade (F/D) since 1900 has not been linear but sigmoidal. The rise accelerated until the mid-1960s, whereupon it seemed to stabilize briefly, before decelerating; F/D finally leveled off or declined in the last two decades (we prorated fatalities to the end of this decade based on numbers during 2010-2017) (R 2 = 99.7%, F = 759, F(4,7) = 7.9, P < 0.00001). We found the same pattern for fatality rate per million humans (F/H) (a) north of Mexico, (R 2 = 99.7%, F=502, P < 0.00001). Rising human abundance statistically explains virtually all variance in rates of fatalities inflicted by black and grizzly/brown bears; however, the mechanism by which this occurs is uncertain. Although black bear abundance also rose during that period, that increase was largely in states south of Canada where there was only a combined total of just 1 fatality. Furthermore, these results provide no support for the first hypothesis that conflict rate per encounter has been increasing-that bears have become more aggressive, whether due to lower hunting pressure or any other cause. On the contrary, fatality rate per encounter has apparently decreased. Deceleration in fatality rate began about when conflict-prevention measures were intensified following the deaths of people in Yellowstone and Glacier National Parks. This evidence that precautions have succeeded on a continental scale augments evidence of success observed at local levels (e.g., in Yellowstone National Park). That warrants increased investment in precautions; not complacency. Precautions should be continued and supplemented with more innovative methods, especially those which reduce mortality of conflict bears. Greater effort should also be invested in better understanding why food conditioning and habituation sometimes reduce risk, contrary to conventional wisdom. Agencies should foster more partnerships with non-governmental wildlife stewards which can provide extra expertise, labor, and funding. www.researchgate.net/publication/333489352_Have_Black_and_Grizzly_Bears_Become_More_Dangerous_Insights_From_Human-Bear_Fatality_Trends |
|
|
|
Post by tyrannosaurs on Aug 3, 2021 4:05:39 GMT -5
Body size of the Black Bear: www.researchgate.net/figure/Body-mass-range-kg-and-sample-size-bear-days-for-sex-and-species-categories-of-bears_fig8_303358206"Body mass range (kg) and sample size (bear-days) for sex and species categories of bears monitored to estimate daily diets, Grand Teton National Park, Wyoming, USA, 2004–2006." Individual black bear (Ursus americanus) age in 2005, capture body mass, number of radiolocations, and mean home-range size. - www.researchgate.net/figure/Individual-black-bear-Ursus-americanus-age-in-2005-capture-body-mass-number-of_tbl1_233693894Growth Rate and Body Size at Maturity of Florida Black Bears - meridian.allenpress.com/jfwm/article/10/2/458/433040/Growth-Rate-and-Body-Size-at-Maturity-of-FloridaPotential mechanisms of phenotypic divergence in body size between Newfoundland and mainland black bear populations: drive.google.com/file/d/1gx-RQqxICATMwo-aIydBzibRzq38wNmF/view?usp=drivesdkThe Demographic and Morphological Characteristics of Black Bears in the Smoky Mountains: drive.google.com/file/d/1gz64QudW3kPpKOuVDRX9dvU_fRNjYPLl/view?usp=drivesdkBear morphology: www.researchgate.net/publication/338410206_Bear_MorphologyThe size present - 60 to 200 kg', total length - 120 to 200 cm', shoulder height - 70 to 100 cm'. American black bear - 60 to 225 kg', total length - 120 to 200 cm', shoulder height - 70 to 100 cm'. I will try and find more. Body condition and growth dynamics of American black bears in northern Canada - "The von Bertalanffy growth function showed that males reached asymptotic body length 9.3% longer, and mass 29.3% heavier, than females." Maybe someone would be able to find the full study but this is the citation: www.jstor.org/stable/41818967 |
|
|
|
Post by tyrannosaurs on Aug 10, 2021 11:01:10 GMT -5
|
|
|
|
Post by Gorilla king on Sept 1, 2021 9:35:55 GMT -5
Age Determination in the Black Bear
Abstract
Age criteria are described for separating black bear (Ursus americanus) into six age-classes as follows: cubs, 1-2, 2-4, 4-6, 6-8, and 8+ years. First described from examinations of the skeletal elements of 25 known-age captives, the age-classes were further refined by examining materials from 29 known-age tagged wild bears and from a series of skeletal materials from 140 other bears. Criteria are based on skull morphology, skull and body measurements, canine cementum layers, tooth replacement and wear, epiphyseal plate and suture coalescence, and baculum growth and maturation. Of these criteria, canine cementum layers are deemed most accurate for determining age. Comparative skeletal growth studies indicated no significant differences between captive and wild bears.
www.researchgate.net/publication/272584675_Age_Determination_in_the_Black_Bear
|
|
|
|
Post by oldindigosilverback on Sept 1, 2021 10:20:08 GMT -5
I guess American black bears are fully mature at 8 years old (for males).
|
|
|
|
Post by Gorilla king on Sept 1, 2021 10:30:57 GMT -5
I guess American black bears are fully mature at 8 years old (for males).
|
|
|
|
Post by Gorilla king on Sept 1, 2021 11:00:44 GMT -5
|
|
|
|
Post by oldindigosilverback on Oct 2, 2021 6:01:34 GMT -5
|
|
|
|
Post by oldindigosilverback on Oct 2, 2021 6:09:16 GMT -5
HERE ARE 13 OF THE BIGGEST BLACK BEARS EVER HUNTEDWhile black bears don't generally grow as large as their brown, grizzly and polar bear cousins, these brutes can get pretty monstrous and scary. Adult black bears typically weigh between 100 and 500 pounds. Anything over that and we're talking humongous territory. But even a 600-pound bear isn't too uncommon. Wikipedia says that, "The biggest wild American black bear ever recorded was a male from New Brunswick, shot in November 1972, that weighed 902 lb after it had been dressed, meaning it weighed an estimated 1,100 lb in life, and measured (7.9 ft long.)." And they're all over. From Georgia to the Western Canadian provinces, and from the Montana foothills to suburban New Jersey, black bears cover a wide range of North American habitat. Here's a random sampling of some of the biggest big black bears that made us drop our jaws. Check out the most humongous black bears. 704-pound black bear.
Biggest Black Bears The Welsboro Gazette 704-pound black bear taken in Pennsylvania by 21-year-old Tyler Wilbur of Annville, Pennsylvania. It is his first black bear and had a chest girth of 64 inches. Tyler stalked the bear in a harvested corn field to take a perfect shot with his crossbow. To give you an idea of proportion and size, Tyler is 6 feet 2 inches tall. 610 pounds...Still a big bear
Biggest Black Bears Rack Em Up Scott Clark's 610-pound bow bear. Over 700 pounds.
Biggest Black Bears WQOW This 700+-pound black bear was killed near Boyceville, Wisconsin when a farmer accidentally ran over it with his combine in a cornfield. Bob Keagy's Alaska black bear.
Biggest Black Bears The Hunting Report "The bear was a beauty, 'squaring' (nose to tail, plus tip of claw to tip of claw, measuring 8 feet and one inch. His skull measured 20 5/16, making the B & C Awards minimum of 20 inches. Both measurements are more common for a grizzly bear than a black bear. We guesstimate the bear's age at over 20 years. What a wonderful experience!" - Bob Keagy Steve and Lorrie Dougherty with Steve's 21 1/16 Boone and Crockett Club black bear.
Biggest Black Bears South Bay Outfitters 21 2/6 Alaska black bear. Texas Bowhunter
Unknown but BIG! Biggest Black Bears Bowhunting World Alberta black bear. Biggest Black Bears Link's Wild Safaris Weight and score unknown. Alaska Prince of Wales black bear.hunting
Biggest Black Bears Alaska Black Bear Hunts The bears on Prince of Wales were recently reclassified by Safari Club International as Coastal Bears or Island Black Bear due to their massive size. There are more record-book black bear entries from here than the rest of North America. They regularly produce monster bruins that weigh over 350 pounds, square out between 7 feet and 8 feet and have skulls that score between 19 1/2 inches and 22 inches. Bob Richardson's Ontario giant
Biggest Black Bears Robinson Outdoors Three 7-foot Canadian giants.
|
|
|
|
Post by oldindigosilverback on Oct 2, 2021 6:19:28 GMT -5
Black Bear
Ursus americanus
DESCRIPTIONNot all black bears are black—their fur can range in color from pure white to a cinnamon color to very dark brown or black. Most populations have a mixture of these colors, including the pure white form, which is found in some individuals in the island archipelago in southern British Columbia (Kermodi Island). This white black bear (called a spirit bear, revered by Native Americans) is caused by a recessive gene from both the mother and the father. Genes can also result in the light gray coat color of the blue bear, or glacier bear, in southeastern Alaska. Despite these genetic variants, most of the bears in any region are black in color. Some bears have a white patch on their chests. They have a short, inconspicuous tail, longish ears, a relatively straight profile from nose to forehead, and small, dark eyes. There are several ways to tell a black bear from a grizzly bear. Black bears and grizzly bears can both have a wide variety of colors and sizes, but most commonly in areas where both species occur, black bears are smaller and darker than grizzly bears. Black bears have longer and less rounded ears and a more straight profile from forehead to nose compared to grizzly bears. Grizzly bears have larger shoulder humps and a more dished-in facial profile and much longer front claws that are evident in the tracks. Black bears in some areas where food is scarce are much smaller than in other areas where food is abundant. Typically adults are three feet tall at the shoulder, and their length from nose to tail is about 75 inches. All bears, including black bears, are sexually dimorphic—meaning adult males are much larger than adult females. A large male black bear can exceed 600 pounds in weight, while females seldom exceed 200 pounds. RANGE
The American black bear's range covers most of the North American continent. They are found in Alaska, much of Canada and the contiguous United States, and extend as far south as northern Mexico. Because of their versatile diet, black bears can live in a variety of habitat types. They inhabit both coniferous and deciduous forests, as well as open alpine habitats. They typically don't occur on the Great Plains or other wide-open areas, except along river courses where there is riparian vegetation and trees. They can live just about anywhere they can find food, but largely occur where there are trees. DIET
American black bears are omnivorous, meaning they will eat a variety of things, including both plants and meat. Their diet includes roots, berries, meat, fish, insects, larvae, grass, and other succulent plants. They are able to kill adult deer and other hoofed wildlife but most commonly are only able to kill deer, elk, moose, and other hoofed animals when the prey are very young. They are able to kill livestock, especially sheep. Bears are very attracted to human garbage, livestock food or pet food, or other human-associated foods like fruit trees. Bears using these human-associated foods can quickly become habituated to them and this commonly results in the bears being killed as nuisances. This is true for bee hives as well, as bears are very attracted to honey. LIFE HISTORY
Black bears are typically solitary creatures, except for family (a female with cubs) groups and during mating season, which peaks in May and June. Following fertilization, the embryo doesn’t implant in the uterus until fall, at the time of den entrance. This process of delayed implantation occurs in all bear species and allows the female bear’s body to physiologically “assess” her condition before implantation occurs and the period of gestation leading to the birth of cubs really begins. Delayed implantation allows the female to not waste fat reserves and energy in sustaining a pregnancy that would have little chance of success because her condition is too poor. Females give birth to cubs every other year if food sources are sufficiently plentiful. In years when food supplies are scarce, a female may skip an additional year or two between litters. The cubs are born in the mother's winter den, and will den with her again the following winter. The following spring, when the cubs are one and a half years old, the cubs and female will separate and the female will breed again. A black bear litter can have one to five cubs, but most commonly litters contain two cubs. Black bears can live up to 30 years in the wild, but most die before they are in their early 20s.
CONSERVATION
The American black bear is not currently a species of conservation concern and even the formerly listed black bear of Florida and Louisiana is now increasing. Habitats in western Texas, from which black bears were extirpated, are now being recolonized. Conservation efforts for black bears have been effective and, in most areas, black bears are increasing and can sustain managed sport hunting. In areas with human populations, this can cause conflicts because bears are very attracted to human foods and refuse, as well as to livestock and livestock foods. Since bears are large and strong animals, many people fear them and resent the damage they can cause. The key to successful coexistence between humans and bears is to recognize that it is no longer possible for either species to occupy all habitats, but that where co-occupancy is possible and desirable, humans must be responsible for the welfare of the bear population. Wild areas with little human footprint will remain the most important habitat for bears, but peaceful coexistence can occur in the urban-wildland interface as long as humans take the necessary steps to assure that the relationship remains a positive one. FUN FACT
Black bears have relatively short claws, which enable them to climb trees. Unlike cats, the claws are non-retractable. www.nwf.org/Educational-Resources/Wildlife-Guide/Mammals/black-bear
|
|
|
|
Post by oldindigosilverback on Jul 1, 2022 6:29:43 GMT -5
|
|
|
|
Post by Montezuma on Jul 10, 2022 1:43:00 GMT -5
|
|
|
|
Post by oldindigosilverback on Jan 8, 2023 5:49:58 GMT -5
/\ They forgot the glacier bear   |
|
.
