Note: Various bear hybrids are known, but the cross between brown bear and polar bear is the most common, especially in captivity.
Helarctos malayanus [Sun Bear]
× Melursus ursinus (♂) [Sloth Bear] CHR(Tokyo). DRS. Gestation of a hybrid lasted 95 days. In one reported case, the hybrid increasingly resembled sloth bear as it matured. Asakura 1969; Fitzgerald and Krausman 2002; International Zoo Yearbook 1969 (Plate 34†); van Gelder 1977b.
× Ursus thibetanus (♀) [Asiatic Black Bear] NHR(Cambodia). CON: southeast Asia. In 2005 an unusual-looking male bear was obtained in an area of dense evergreen forest along the O’Koki River (at 14˚1.79’ S, 105˚20.39’ E) in Preah Vihear Province. Morphological and genetic data confirmed it to be a hybrid of this type. The hybrid was grossly similar to a sun bear, especially postcranially, but it had U. thibetanus mitochondrial DNA, and the ears and canines were also similar those of a sun bear. No hybridization of these two bears had been previously reported. Galbreath et al. 2008†. Internet Citations: BEARB.
Melursus ursinus [Sloth Bear]
See also: Helarctos malayanus.
× Ursus thibetanus [Asiatic Black Bear] CHR. Formerly, these bears were in parapatric contact in what is now western Pakistan and northern India. Scherren 1907.
× Ursus arctos [Brown Bear] CHR. CON: Himalayas. A hybrid of this type is listed in the twenty-first annual report of the New York Zoological Society (1916, p. 75; see: tinyurl.com/nlpagz5) as having been born at the New York Zoological Park (now the Bronx Zoo) in 1916. Two years later it was destroyed due to its "becoming so savage that it was extremely dangerous for the keepers to enter the dens at cleaning time" (See: tinyurl.com/mq6b4wh, p. 66).
Thalarctos maritimus [Polar Bear]
× Ursus arctos (usu. ♀) [Brown Bear] CANHR. HPF(♂&♀). See the separate article "Polar Bear × Brown Bear."
Tremarctos ornatus [Spectacled Bear]
× Ursus thibetanus (♀) [Asiatic Black Bear] CHR. DRS. A male hybrid was born at the Parque Zoológico de Las Delicias, Maracaibo, Venezuela in September 11, 1975. The hybrid was black except for a whitish underlip and jaw. U. thibetanus occurs in Asia, T. ornatus, in the Andes of northwestern South America. Mondolfi and Boede 1981.
Ursus americanus [Black Bear]
× Bos taurus [European Domestic Cattle] See the separate article about cow-bear hybrids.
× Canis familiaris [Domestic Dog] See the separate article about dog-bear hybrids.
× Homo sapiens [Human] See the separate article about human-bear hybrids.
× Ursus arctos (↔) [Brown Bear] CANHR. HPF. CON: North America. Hybrids of both sexes have been reported and a successful backcross to brown bear has occurred. A bear shot in Alaska was thought to be a record black bear, but was sent to the National Museum of Natural History and identified as a natural hybrid, the first known of this type. The skull of the hybrid was one of the largest ever recorded, even for a brown bear. Bartlett 1860; Barlett Society; Crandall 1964; Flower 1929a (p. 151); International Zoo Yearbook 1966 (p. 394), 1967 (p. 311);1969 (p. 227), 1970 (p. 262), 1971 (p. 274); Scherren 1907; 32nd Report of the Zoological Society of Philadelphia 1904 (p. 15). Internet Citations: PINTO.
× Ursus thibetanus (♀) [Asiatic Black Bear] DRS. According to Jack Hanna's Monkeys on the Interstate, a bear captured in Sanford, Florida was thought to have been the offspring of an escaped female Asian black bear and an American black bear.
Note: Here, middendorffi is included in Ursus arctos.
Ursus arctos [Brown Bear]
See also: Melursus ursinus, Thalarctos maritimus, Ursus americanus
× Bos taurus [European Domestic Cattle] See the separate article about bear-cow hybrids.
× Canis familiaris [Domestic Dog] See the separate article "Bear-dog Hybrids."
× Capra hircus [Domestic Goat] See the separate article "Bear-goat Hybrids."
× Equus caballus [Horse] See the separate article "A Bear-horse Hybrid?"
× Homo sapiens [Human] See the separate article "Bear-human Hybrids."
× Ursus thibetanus [Asiatic Black Bear]CHR. CON: Asia. The St. Petersburg Zoo (Russia) has reported hybrids of both sexes. Barlett Society; International Zoo Yearbook 1971 (p. 274), 1974 (p. 379), 1975 (p. 373), 1977 (p. 315).
Ursus thibetanus [Asiatic Black Bear] See: Helarctos malayanus; Melursus ursinus; Tremarctos ornatus; Ursus americanus, Ursus arctos.
By the same author: Handbook of Avian Hybrids of the World, Oxford University Press (2006).
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