Bear-dog Hybrids

Fact or fiction?

Mammalian Hybrids



I am obliged to report that which is reported, but not to believe it.
—Herodotus, The History, VII, 152
black bear Black bear, Ursus americanus

This cross, which is interfamilial (Canidae × Ursidae), is listed in various older works. However, the disparity of the cross and the old and unreliable nature of the documenting sources raise many questions, for example, the following article, quoted in its brief entirety from the American Veterinary Review (1905-6, vol. 29, p. 408), seems to be the only scientific paper ever reporting such a hybrid:

Ursus-Canis (Presumably [Ursus] Americanus). — Half bear half dog, a remarkable prodigy of nature, was brought to the city [Denver, Colorado] Wednesday morning from Nebraska by I. Pinter. It is the only known example of the crossing of the dog and bear families. “Teddy” is the name of the hybrid. His mother was a common stray dog of North Platte, Neb., a little bigger than a Scotch terrier and of the same general build and color. Father Bear has never been seen. The dam gave birth to a litter of five of the strange puppies, but four were born dead. The creature is now eleven months old and weighs about thirty-five pounds, but looks much heavier. At first sight the animal gives the impression of a peculiar kind of dog, although on closer examination the bear peculiarities are more evident. The ears are long and drooping, like those of a spaniel, the tail is also that of a spaniel. The eyes are large and have the mild, dog like expression. A bear has short upstanding ears, a stub tail never more than a couple of inches long and the eyes are small and quite different in expression and the manner they are set in the head. But the bear hump is very plain above the hindquarters. The legs are bear paws thick as a man’s arm and short, with pads, that will in time make an impression similar to the human foot, and the claws are long. Teddy has never been heard to bark, but will occasionally give a modest bear’s growl. In habits he is more like a bear than a dog, lying down on his side like bruin instead of upright as is the fashion in the canine world. He always lies down to eat. The animal shows very little intelligence and energy. He has not strength enough to walk upstairs and will refuse to go more than a mile at a time unless very slow progress is made.

Another report, dating to the early part of the twentieth century, appeared on page 8, column 4, of the January 11, 1911, issue of The Yakima Herald, a newspaper published in Yakima, Washington (source):


Asked to Bring “Bear-Dog” to Celebration of Founding of City—Will Participate in Centennial Which is Being Planned.

John Jacob Astor IV John Jacob Astor IV
    PORTLAND, Ore., Jan. 10—(Special)—People of Astoria, Ore., who will celebrate the centennial of the founding of that city next summer, it being the first American settlement on the Pacific coast, are much interested in announcements that Col. John Jacob Astor, descendant of the founder of their town, has found a rare curiosity in his “bear-dog,” and will ask him to bring this strange animal to the celebration.
    Col. Astor, according to reports which have excited the Astorians, has an animal that is plainly half dog and half bear. He bought it from gypsies n the Pyrenees Mountains. He says it walks with a “waddling gait,” and is wholly unknown to the common or garden variety of scientists that infest New York.
Looks Like a Bear
    One attempts to explain the freak by saying it is a young St. Bernard and another inclines to the belief that the gypsies sold a dwarf bear to the colonel. But the fact remains that the “bear-dog” is unlike anything ever seen before and Col. Astor has offered $5000 to anyone who would enter in the dog show at Madison Square Garden in New York a similar “bear-dog.”
    So the scientists and near-scientists of Manhattan are said to be running around in circles, giving tongue to yelps of irritation. To some thoughtful ones, however, the freak animal suggests unlimited possibilities. If it is possible to cross bears and dogs, they say there is no end to the changes they can make in the animal kingdom. Recent experiments whereby scientists have produced enormous frogs by dissecting, combining and fertilizing eggs lend encouragement to this hope.
    Col. Astor is expected to represent his illustrious ancestor of the same name at the Astoria Centennial and will probably be made honorary chairman of the affair. People of the coast hope to have a look at the “bear-dog.”

One of the richest men in America, Astor later drowned in the sinking of the Titanic.

Older reports of this cross exist as well. Writing during the Elizabethan era, the French humanist Pierre Boaistuau, in his Histoires prodigieuses, says dogs and bears were intentionally mated in London and that sometimes a hybrid resulted.

bear-dog hybrid Woodcut illustration of an alleged bear-dog hybrid (Boaistuau 1591, p. 206).

mastiff 17th-century depiction of a mastiff.

Amphicyon ingens
Prehistoric Bear-dogs
Fossils demonstrate the former existence of animals known as bear-dogs (Family Amphicyonidae, 46.2-1.8 mya) and dog-bears (Family Hemicyonidae, 33.9–5.3 mya). These creatures were so named because they had both bear- and dog-like traits. An example of the bear-dog Amphicyon, is shown above and an artist’s reconstruction of the dog-bear Hemicyon appears below.


brown bear
Brown bear
Ursus arctos

He includes an illustration of a alleged bear-dog hybrid (above), supposedly born of a bitch mated with a bear (“La mere qui la porta estoit chiene, & le masle qui la couvrit estait ours.”). Bears and dogs, usually mastiffs, were kept to fight in the bear baitings so popular at the time. An English translation of the passage in question (Boaistuau 1591, pp. 133-135) reads as follows:

This monstrous animal, which you see illustrated at the beginning of this chapter, was engendered by an English bitch covered by a bear. As a result, it partakes of the nature of both, which will not seem strange to those who have observed how in London dogs and bears are kept in small cages near each other. Their keepers cage a bear and a dog together when they are in heat, so that pressed by their natural urges, they convert their cruelty into love. From such conjunctions are sometimes born animals like this one, albeit quite rarely. Among these I have seen two, which were given to his grace the Marquis de Trans. One of these he gave to my lord the Conte d’Alphestan, the Emperor’s ambassador. The other, he had taken to France, which I have had reproduced here. The illustrator has omitted nothing. [Translated by E. M. McCarthy. Original French.]

Boaistuau then turns to a discussion of other types of hybrids, but eventually returns to his description of the bear-dog:

But to return to the description of our animal, of which you can see the appearance is so monstrous, it resembles a small bear, and is also in its movements, its voice, and manner of doing all things more like a bear than a dog. Moreover, I can assure you that he is one of the most ferocious beasts that you will ever see, for there is no species of animal that he will not attack, be it a bear, a lion, or a bull, or others of a similar kind. And he is so ardent in these combats that once he has sunk his teeth into some beast, he would rather be dismembered than relinquish his grip, as I can attest after witnessing him in combat against a bear in London. [Translated by E. M. McCarthy. Original French.]

The exact identity of the bears involved in Elizabethan bear baitings is somewhat in doubt. But it does seem that the Brown Bear (Ursus arctos) is the animal in question. As Henry Reeks (1878) states in a scholarly article on mammals mentioned by Shakespeare, the brown bear (he refers to Ursus arctos and to its synonym Ursus isabellinus) “would probably be the bear with which Shakspeare [sic] would be most familiar. Bear baiting seems to have been a very popular amusement about that period and for many years subsequently.”

bear baiting An Elizabethan bear baiting

Though one might suppose that a brown bear would be far too large to mate with a dog, there is a very wide range of geographic variation in the adult size of these animals. Nowak (1999, pp. 685-686) states that while brown bears may weigh as much as 780 kg (1720 lbs) on the southern coast of Alaska, elsewhere they can be far smaller. For example, the average figure he gives for southern Europe is just 70 kg (154 lbs). It does seem, then, that some bears would be within the size range that would allow mating with a large dog.

Jakob Benjamin Fischer, too, in his Naturgeschichte von Livland (1791, p. 146), mentions a bear-dog hybrid that was supposedly fertile. He gives the cross in the same direction as in the account of the Denver hybrid (female dog/male bear), but in the opposite direction from that specified by Boaistuau:

One has the example of a bear mixing sexually with a dog. In Riga, a male bear mated with a bitch, which went on to produce offspring. Among these was a remarkable dog. He had a bear’s head and no tail. His voice was a dog’s bark mixed with the growling of a bear. They let this dog mate with a bitch, but no great caution was taken—she probably mated with other dogs—and at her expected time she gave birth to sixteen puppies (an unusual example of canine fertility) of which only six resembled the bear hybrid, with bear’s heads, shaggy coats, and no tails. One sees from this, that it is in fact possible for hybrid beasts to produce offspring. [Translated by E. M. McCarthy.]

Scherren (1907, pp. 432-433) provides a brief review of reports alleging the occurrence of this cross.

Of course, nowadays dogs and bears are very rarely kept caged together, and it seems no one has tried to cross them by artificial insemination. Therefore, in the absence of experimentation, it must remain an open question whether the various early reports of this type of hybrid have any basis in fact.

The gestation periods of dogs and bears differ widely (a little over two months in the former versus 7 months in the latter).

The chromosome counts of dogs and bears are fairly similar (in dogs, 2n=78, in both black and brown bears, 2n=74).

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Biology Dictionary >>

By the same author: Handbook of Avian Hybrids of the World, Oxford University Press (2006).

An account of Elizabethan bull and bear baiting
“There is still another place, built in the form of a theatre, which serves for the baiting of bulls and bears they are fastened behind and then worried by great English bull-dogs but not without great risk to the dogs from the horns of the one and the teeth of the other; and it sometimes happens that they are killed upon the spot, fresh ones are immediately supplied in the places of those that are wounded or tired.” (from Travels in England During the Reign of Queen Elizabeth by Paul Hentzner and Sir Robert Naunton)

On bear baiting
(from Chambers 1864)

“In the twelfth century, the baiting of bulls and bears was the favourite holiday pastime of Londoners; and although it was included in a proclamation of Edward III, among ‘dishonest, trivial, and useless games,’ the sport increased in popularity with all classes. Erasmus, who visited England in the reign of Henry VIII, speaks of ‘many herds’ of bears regularly trained for the arena; the rich nobles had their bearwards, and the royal establishment its ‘master of the king’s bears.’ For the better accommodation of the lovers of the rude amusement, the Paris Garden Theatre was erected at Bankside, the public being admitted at the charge of a penny at the gate, a penny at the entry of the scaffold, and a penny for quiet standing. When Queen Mary visited her sister during her confinement at Hatfield House, the royal ladies were entertained with a grand baiting of bulls and bears, with which they declared themselves ‘right well contented.’ Elizabeth took especial delight in seeing the courage of her English mastiffs pitted against the cunning of Ursa and the strength of Taurus. On the 25th of May 1559, the French ambassadors ‘were brought to court with music to dinner, and after a splendid dinner, were entertained with the baiting of bears and bulls with English dogs. The queen’s grace herself, and the ambassadors, stood in the gallery looking on the pastime till six at night.’ The diplomatists were so gratified that her majesty never failed to provide a similar show for any foreign visitors she wished to honour.”

bear garden
The Paris Garden Theatre, Bankside, the primary venue for bear baitings in old London (engraving from Chambers 1864, vol. II, p. 57)

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