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What the sources say

Grizzly BearUrsus arctos horribilis

Every figure, record and mechanism on the Grizzly Bear profile was written from a source, and this is the working table behind it: 48 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

Animal Diversity Web, University of Michigan

Ursus arctos (brown bear). Animal Diversity Web, University of Michigan.

The page saysThe IUCN rates the whole species, Ursus arctos, as Least Concern worldwide
The source saysIUCN Red List Least Concern
The page saysdig a ground squirrel out of its burrow
The source saysalso dig mice, ground squirrels, marmots, and other fossorial animals out of their burrows

Source
02

U.S. Fish and Wildlife Service, Species Profile

Ursus arctos horribilis (Grizzly Bear). U.S. Fish and Wildlife Service, Species Profile.

The page saysIn the lower 48 states, an adult male grizzly averages 400 to 600 pounds (200 to 300 kilograms) and an adult female 250 to 350 pounds (110 to 160 kilograms)
The source saysAdult males average 400 to 600 pounds (200 to 300 kilograms) and adult females 250 to 350 pounds (110 to 160 kilograms) in the 48 contiguous states.
The page saysAt least 1,923 grizzlies live in the lower 48 states, and the U.S. Fish and Wildlife Service lists that population as threatened
The source saysCurrently, there are at least 1,923 individuals in the 48 contiguous states ... Grizzly bears in the 48 contiguous states are currently protected as a threatened species.
The page saysdig its den, usually on a steep slope
The source saysGrizzly bears usually dig dens on steep slopes
The page saysIn preparation for hibernation, a grizzly goes through hyperphagia, a feeding binge in the two to four months before it enters its den
The source saysIn preparation for hibernation, bears increase their food intake dramatically during a period called hyperphagia. Hyperphagia occurs throughout the two to four months prior to den entry
The page saysfemale grizzlies with less than 20 percent body fat are unlikely to produce cubs, even when they have mated
The source saysa body fat threshold may exist below which females may not produce cubs, even when bred; studies have shown that females with less than 20% body fat are unlikely to produce cubs
The page saysFor four to six months in the den, a grizzly does not eat, drink, urinate, or defecate
The source sayshibernate in dens for four to six months each year ... During this period, bears do not eat, drink, urinate or defecate.
The page saysDuring hyperphagia, the fall feeding binge that fattens bears up for hibernation
The source saysIn preparation for hibernation, bears increase their food intake dramatically during a period called hyperphagia. ... During hyperphagia, excess food is converted into fat

Source
03

National Park Service, Yellowstone National Park (Yellowstone Science 23(2))

Yellowstone Grizzly Bear Facts. National Park Service, Yellowstone National Park (Yellowstone Science 23(2)).

The page saysclaws built for digging
The source saysclaw length and shape allow efficient digging of foods from the ground
The page saysa fall feeding binge of about 20,000 calories a day
The source sayshyperphagia: 20,000 kcal/day
The page saysYellowstone grizzlies' claws, up to 5.9 inches long, are shaped for digging food out of the ground
The source saysClaw Length: average 1.8 inches (45 mm), longest 5.9inches (150 mm);claw length and shape allow efficient digging of foods from the ground
The page saysthey can run 35 to 40 miles an hour
The source saysSpeed: 35-40 mph
The page saysIn Yellowstone, grizzly claws average 1.8 inches (45 millimeters), and the longest measured 5.9 inches (150 millimeters)
The source saysClaw Length: average 1.8 inches (45 mm), longest 5.9inches (150 mm)
The page saysTheir length and shape make them good for digging food out of the ground but worse than a black bear's for climbing trees
The source saysclaw length and shape allow efficient digging of foods from the ground but are less efficient for tree climbing than black bear claws
The page saysthe National Park Service lists a Yellowstone grizzly's top speed at 35 to 40 miles an hour
The source saysSpeed: 35-40 mph
The page saysYellowstone's figures put its intake at about 20,000 calories a day during hyperphagia, more than double the 5,000 to 8,000 it eats on a normal day
The source saysCaloric Requirements: normal (May-Sept): 5,000-8,000 kcal/day; hyperphagia: 20,000 kcal/day
The page saysGrizzlies are shallow hibernators
The source saysbears are shallow hibernators
The page saysbody temperature dropping only a few degrees, from 36.5 to 38.5°C in the active season to 34.4 to 35°C in hibernation, while heart rate falls from 40 to 50 beats a minute to 8 to 19
The source saysBody Temperature: 36.5-38.5°C (98-101°F) during active season;34.4-35°C (94-95°F) during hibernation ... Heart Rate: 40-50 beats per minute; 8-19 beats per minute during hibernation
The page saysa grizzly bear's calorie intake can climb to about 20,000 calories a day, more than double the 5,000 to 8,000 calories it eats on a normal day
The source saysCaloric Requirements: normal (May-Sept): 5,000-8,000 kcal/day; hyperphagia: 20,000 kcal/day

Source
04

National Park Service

Brown Bears. National Park Service.

The page sayswhitebark pine seeds
The source saysIn the fall, whitebark pine seeds are a preferred food for grizzly bears
The page sayselk calves, ground squirrels, and spawning trout
The source saysprey on vulnerable animals such as elk calves and spawning troutNote: ground squirrels: adw-ursus-arctos 'also dig mice, ground squirrels, marmots, and other fossorial animals out of their burrows'
The page saysWhitebark pine seeds are a favorite fall food
The source saysIn the fall, whitebark pine seeds are a preferred food for grizzly bears
The page saysgrizzlies also prey on elk calves and spawning trout
The source saysThey are effective predators and prey on vulnerable animals such as elk calves and spawning trout

Source
05

National Park Service

Bear Identification. National Park Service.

The page saysbears along the coast of Alaska are called brown bears, while the typically smaller inland bears, with little or no access to food from the sea, are called grizzlies
The source saysThose that live in coastal areas of Alaska are called brown bears, while typically inland bears that have limited or no access to marine-derived food resources are often smaller and called grizzlies.
The page sayswhich black bears lack
The source saysDistinctive shoulder hump. ... Shoulder lies level or flat with back/lacks shoulder hump.Note: first fragment is the brown/grizzly bear, second the American black bear, in the page's side-by-side list

Source
06

San Diego Zoo Wildlife Alliance

Brown Bear. San Diego Zoo Wildlife Alliance.

The page saysThe most distinctive shoulder hump of any brown bear
The source saysgrizzly bears have the most distinctive hump of all
The page saysroots, insects
The source saysBears dig for roots, tubers, and insects
The page saysSan Diego Zoo Wildlife Alliance says the coastal bears tend to be the largest, from eating fat-rich salmon every summer
The source saysBears found in parts of coastal Alaska are called Kodiak or Alaskan brown bears and tend to be the largest. This is from eating salmon rich in fat every summer.
The page saysdespite its reputation the grizzly is one of the smallest brown bear subspecies
The source saysDespite its "large" reputation, the grizzly bear is one of the smallest of the brown bear subspecies.
The page saysGrizzlies carry a large hump of muscle on their shoulders
The source saysBrown bears have a large hump of muscle on top of their shoulders
The page saysSan Diego Zoo Wildlife Alliance says grizzlies have the most distinctive hump of any brown bear
The source saysgrizzly bears have the most distinctive hump of all
The page saysdig for roots and insects
The source saysBears dig for roots, tubers, and insects
The page saysA large hump of muscle on top of the shoulders
The source saysBrown bears have a large hump of muscle on top of their shoulders
The page saysSan Diego Zoo Wildlife Alliance says all brown bears have one, and grizzlies have the most distinctive hump of all
The source saysBrown bears have a large hump of muscle on top of their shoulders, and grizzly bears have the most distinctive hump of all.
The page saysTheir great front claws make brown bears powerful diggers
The source saysTheir great front claws make all brown bears powerful diggers.

Source
07

Draper Natural History Museum, Buffalo Bill Center of the West

Greater Yellowstone Grizzly Bear and Army Cutworm Moths. Draper Natural History Museum, Buffalo Bill Center of the West.

The page saysArmy cutworm moths
The source saysA key food source in mid – late summer is the army cutworm moth.
The page sayshundreds of thousands of them migrate into the Rocky Mountains each year and rest under rocks in high boulder fields, and a single grizzly may eat more than 40,000 of them in one day
The source saysEach year, many hundreds of thousands of moths migrate from lowlands as much as 300 miles east of the Yellowstone to feed on the nectar of alpine wildflowers high in the Rocky Mountains. They feed at night and rest during the day under rocks in large boulder fields ... A grizzly bear may eat more than 40,000 moths in a single day.
The page saysA moth that migrates by the hundreds of thousands up into the Rocky Mountains each year to feed on alpine wildflowers, then rests by day under rocks in high boulder fields
The source saysEach year, many hundreds of thousands of moths migrate from lowlands as much as 300 miles east of the Yellowstone to feed on the nectar of alpine wildflowers high in the Rocky Mountains. They feed at night and rest during the day under rocks in large boulder fields
The page saysgrizzlies comb those boulder fields, turning over rocks and scooping up dozens of moths at a time, and a single bear may eat more than 40,000 moths in one day
The source saysBoth grizzly and black bears exploit this rich food source by combing through high mountain boulder fields, turning over rocks and scooping up dozens of moths at a time. A grizzly bear may eat more than 40,000 moths in a single day.
The page saysa bear that combs a boulder field turning over rock after rock, scooping up dozens of moths at a time
The source saysBoth grizzly and black bears exploit this rich food source by combing through high mountain boulder fields, turning over rocks and scooping up dozens of moths at a time.Note: vibe.reason; the repeated flip-and-scoop is the loop the cycling guitar figures match
The page sayscan eat more than 40,000 of them in a single day
The source saysA grizzly bear may eat more than 40,000 moths in a single day.Note: vibe.reason

Source
08

Evans et al. 2016

Evans et al. (2016). Drivers of hibernation in the brown bear. Frontiers in Zoology.

The page saysA study that tracked brown bears in Sweden, the same species as the grizzly
The source saysphysiological parameters of brown bears in SwedenNote: same species: the grizzly is a brown bear subspecies (sandiegozoo-brown-bear)
The page saysthey entered their dens once snow arrived and the air reached freezing
The source saysBears entered the den when snow arrived and when ambient temperature reached 0 °C.
The page saystheir body temperature began rising about two months before they left, driven by the outside air temperature
The source saysthe unexpected early rise in T b (two months before den exit) was driven by T A
The page saysA study that tracked wild brown bears in Sweden
The source saysphysiological parameters of brown bears in Sweden
The page saysfound they entered their dens once snow arrived and the air temperature reached freezing
The source saysBears entered the den when snow arrived and when ambient temperature reached 0 °C.
The page saysTheir body temperature then began rising about two months before they left the den, driven by the outside air temperature
The source saysthe unexpected early rise in T b (two months before den exit) was driven by T A

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.