Ursid hybrid

An ursid hybrid is an animal with parents from two different species or subspecies of the ursidae (bear) family. Species and subspecies of bear known to have produced offspring with another bear species or subspecies include brown bears, black bears, grizzly bears and polar bears, all of which are members of the ursus genus. Bears not included in the ursus genus, such as the Giant Panda, are probably unable to produce hybrids.

Brown Bear/Black Bear Hybrids

In 1859, a black bear and a European brown bear were bred together in the London Zoological Gardens, but the three cubs did not reach maturity. In "The Variation Of Animals And Plants Under Domestication," Charles Darwin noted:

In the nine-year Report it is stated that the bears had been seen in the Zoological Gardens to couple freely, but previously to 1848 had most rarely conceived. In the Reports published since this date three species have produced young (hybrids in one case)...

Brown Bear/Grizzly Bear Hybrids

Hybrids between the brown bear and the grizzly bear (considered by some to be a variety of brown bear rather than a separate species) have been bred in Cologne, Germany.

Brown Bear/Polar Bear Hybrids

• Since 1874, at Halle, a series of successful matings of polar bears and brown bears were made. Some of the hybrid offspring were exhibited by the London Zoological Society. The Halle hybrid bears proved to be fertile, both with one of the parent species and with one another. Polar bear/Brown bear hybrids are white at birth but later turn blue-brown or yellow-white.

• In 1936, a male polar bear accidentally got into an enclosure with a female Kodiak (Alaskan Brown) bear at the US National Zoo resulting in three hybrid offspring. One hybrid was named Willy and grew into an immense specimen. The hybrid offspring were fertile and able to breed successfully with each other, indicating that the two species of bear are closely related.

• In a 1970 National Geographic (Vol 137:4, April 1970) article, "White Tiger in My House", Elizabeth C. Reed mentions being foster mother to 4 hybrid bear cubs from the National Zoological Park in Washington where her husband was director.

• DNA studies indicate that some brown bears are more closely related to polar bears than they are to other brown bears, raising whether they are truly separate species. All the Ursinae species (i.e., all bears except the giant panda and the spectacled bear) appear able to crossbreed.

• In 2006 a unusual looking polar bear shot by a sports hunter in the Northwest Territories, was shown to be a Grizzly/Polar Bear Hybrid by DNA testing. This is thought to be the first recorded case of interbreeding in the wild. [1]

See also

• Bear

References

• Martin, P.L. 1876. "Ursus arctos and Ursus maritimus. On bastards between these species born in Nill's menagerie at Stuttgart." Zoologische Garten, 1876:20-22. [Zoologische Garten, 1877:135-136. *W. Stendell and E. von Martens, tom. cit., pp.401-402.]
• ------. 1882. "On a hybrid between a male Ursus maritimus and a female Ursus arctos." Zoologische Garten, 1882:xxiii, 370.
• Kowalska, Z. 1962. "Intergeneric crossbreed of the brown bear Ursus arctos L., and the polar bear Thalarctos maritimus (Phipps)." Przeglad Zoologiczny, 6:230, 1 pl. [Polish with English summary.]
• ------. 1965. "Cross breeding between a female European brownbear and a male polar bear in Lodz Zoo." Przeglad Zoologiczny, 9:313-319. [Polish with English summary.]
• ------. 1969. "A note on bear hybrids Thalarctos maritimus and Ursus arctos at Lodz zoo." International Zoo Yearbook, 9:89.
• Reed, Elizabeth C. "White Tiger in My House." National Geographic (Vol 137:4, April 1970)