GRIZZLY OR BROWN BEAR
Ursus arctos Linnaeus 1758
Order Carnivora : Family Ursidae
DESCRIPTION. Largest of the carnivores in western United States; head large with face distinctly concave in appearance; body robust; legs strong, massive, and relatively short; tail much shorter than hind foot; last upper molar about as large as the two teeth in front of it combined; front claws 7–12 cm in length; upperparts brownish or yellowish brown, often with intermixture of white-tipped hairs; underparts similar to upperparts but lacking white-tipped hairs. Dental formula: I 3/3, C 1/1, Pm 4/4, M 2/3 × 2 = 42. External measurements of an adult male: total length, 2.0 m; length of tail, 76 mm; hind foot, 280 mm; height at shoulder, 1.0 m. Females smaller. Weight of males, 180–360 kg, occasionally >500 kg; of females, 130–180 kg, occasionally >360 kg.
DISTRIBUTION. The brown or grizzly bear probably was a rare inhabitant of the Trans-Pecos region until the early to mid-1800s. Only one specimen of grizzly bear is available from Texas. According to Vernon Bailey, who in 1905 wrote of this bear in his Biological Survey of Texas, a large and very old male grizzly was killed in the Davis Mountains in October 1890 by C. O. Finley and John Z. Means. Measurements of the skull are greatest length, 370 mm; basal length, 310 mm; zygomatic breadth, 220 mm; mastoid breadth, 157 mm; interorbital breadth, 71 mm; postorbital breadth, 69 mm. Finley reported that the claws on the front feet were about 3.5 inches (9 cm) long, and the color of the bear was brown with gray tips to the hairs. Its weight was estimated at 1,100 pounds (500 kg) "if it had been fat." Finley found that the bear had killed a cow and eaten most of it in a gulch near the head of Limpia Creek, where the dogs took the trail. Out of a pack of 52 hounds, only a few would follow the trail, although most of them were used to hunting black bear. Those few followed rather reluctantly, and after a run of about 8 km (5 mi.) over rough country, they stopped the bear, which killed one of them before it was shot by Finley and Means. It took four men to lift the skin, with head and feet attached, onto a horse for the return to camp.
Walter Dalquest reported examining the partial skull of a grizzly bear that had washed out on the banks of the Red River (Montague County) in about 1950. Unfortunately, that specimen has since been lost, and a recent revision of Texas bears by Fred Stangl and RDB suggests that this specimen probably was an exceptionally large black bear (see "Remarks").
SUBSPECIES. Ursus a. horribilis is the historical subspecies in Texas.
HABITS. Today, the grizzly is restricted to rough, mountainous habitats, but considerable evidence suggests that 100 years ago it occupied portions of the plains regions of the United States. Increasing contact with settlers, ranchers, farmers, and urban areas has greatly reduced the range of the grizzly.
Like the black bear, the grizzly does not truly hibernate but holes up in a den and sleeps through the severe part of the winter, subsisting on fat stored in the body. Mating occurs in May to July, but implantation of the fertilized eggs is delayed until November or December. Gestation seems to vary, as Seton reported a gestation period of 180–187 days and Brown reported 236 days. One to four cubs (usually two) are born 6 or 7 months later while the mother is in her winter den. The cubs weigh about 750 g at birth and are about 20 cm long. Their eyes open in 8 or 9 days, in contrast to 6 weeks in the black bear.
The natural food of grizzlies is variable. Results of a study in Montana revealed the following diets: early spring, winter-killed animals, green grasses, and weeds; in middle and late spring, bulbs and roots, increasing use of grasses and sedges, few rodents, occasional young elk calves; in summer, continued use of green vegetation, ants, beetles, and other insects, fruits and berries, few rodents; in fall, largely pine nuts, few rodents. In certain areas they feed extensively on salmon during the spring run; occasional individuals turn renegade and become killers of livestock.
POPULATION STATUS. Extinct. The grizzly was probably an extralimital species in Texas. Only one specimen has been reported (see below), and only a few fossil records are known. Most likely, the grizzly population in Texas was composed of a few individuals that were transients from Mexico or were associated with the southern extensions of the Rocky Mountains in New Mexico.
CONSERVATION STATUS. The IUCN lists the grizzly bear's status as least concern and stable in numbers. On the federal level, it is listed as threatened by USFWS. It is not listed by TPWD due to its extirpation from the state. It is unlikely that the grizzly will be reintroduced into Texas.
REMARKS. In 2014, Fred Stangl of Midwestern State University and RDB examined all black bear and grizzly bear material from Texas and southern Oklahoma and concluded that nearly all of the fossil materials from this region, previously assigned to grizzly bears, were in fact examples of black bears. Consequently, the only currently known grizzly bear record from Texas is the one reported by Bailey from the Davis Mountains.
From The Mammals of Texas, Seventh Edition by David J. Schmidly and Robert D. Bradley, copyright © 1994, 2004, 2016. Courtesy of the University of Texas Press.