Wild Dogs

The Bush Dog. The Bush Dog, Speothos venaticus, is a native of. South America and southernmost North America. It is a small wild canid that resembles externally several members of the weasel family. Few persons who consider themselves dog fanciers would include this small dog in the same family with domestic dogs, wolves and foxes.

The Bush Dog has many different names applied to it by local people who often have their own dialect. Insofar as experts can determine, the Bush Dog lives in Brazil, the Guiana, Paraguay, eastern Peru and northern Bolivia in South America. In North America it is known only from southern Panama. Bush Dogs are small strong canids that whine and squeal and can make short doglike barks. The legs short and stout, the feet have thick pads, and the Bush Dog has a short thick tail with long hairs which cannot however be described as "bushy". Adult Bush Dogs generally measure about 32 inches in length from the tip of the nose to the end of the tail and usually weigh between 10 and 15 pounds. The Bush Dog's face is perhaps the most remarkable aspect of its external features. The short ears are low-set and rounded, the eyes are dark, rounded and fairly bulging, the muzzle moderately short and narrow. Head on the Bush Dog looks remarkably like a large weasel.

The Bush Dog's fur is long and basically brownish. The front part of the body has an orange, tawny or white cast, differing from the hind quarters which are dark brown or blackish. The natural history and ecology of the Bush Dog are poorly known even to specialists in the field of mammalogy. It is thought that these dogs frequent forested areas as well as savannahs and often live where there is sandly soil. Bush Dogs prepare small dens or burrows of their own but sometimes borrow excavations made by other animals.

Bush Dogs are nocturnal and reputed to hunt in small packs. They feed on a variety of things but seem to favor mice and other rodents. They differ from most of their canid relatives in that they have a well-developed ability to dive and swim under water; they are known to pursue prey into rivers. Little is known about the reproduction of Bush Dogs, though young have been born and raised in captivity at the San Diego Zoo. Litters of four and five have been reported. The mating season and number of litters per year in the wild are as yet unknown but once a pregnant female accompanied by two young was found swimming across a tropical river in the month of July. On this basis it might be suggested that Bush Dogs have two litters per year, not unusual for mammals living in tropical regions where the weather is suitable for raising offspring almost year-round.

Scientists are unsure of just how Speothos is related to other canids. The name Speothos was first applied to the Bush Dog in 1839 when the only known specimens were fossils from Brazil. The single species Speothos venaticus has been placed in the subfamily Simocyoninae, a group comprised mostly of wild dogs now extinct.

Domestic dogs, wolves, coyotes and foxes all have three lower molars on each side. The Bush Dog differs from all these in having at most only two lower molars on each side of the jaw - the Bush Dog is especially unusual because the total number of molars varies between individuals - an example of dental polymorphism.