Bush dog (Speothos venaticus)
|Also known as:||cachorro-do-mata, savannah dog, vinegar dog, zorrito vinagre|
|French:||Chien Des Buissons, Zorro|
|Spanish:||Cachorro Vinagre, Guanfando, Pero Selvático, Perrito de Monte, Perrito Venadero, Perro de la Selva, Perro Grullero, Perro Vinagre, Umba, Zorrito Vinagre, Zorro Pitoco, Zorro Vinagre|
|Size||Head-body length: 57 - 75 cm (2)|
Shoulder height: 20 - 30 cm (2)
|Weight||5 - 8 kg (2)|
Classified as Near Threatened (NT) on the IUCN Red List (1) and listed in Appendix I of CITES (3).
The bush dog is a rare, little known and unusual canid. It has a rather squat body and is said to look more like a mustelid (the family of badgers and otters) than a member of the dog family (2). It is adapted to a semi-aquatic life amongst the forest (4), and has short legs, a short, bushy tail, a rounded muzzle and ears, and webbed feet (2). The head and neck are reddish in colour, and the brown back becomes darker towards the tail. The underside is dark in colour and there is occasionally a lighter throat patch (2). A large range of contact calls are produced, possibly because visual communication is difficult in the forest (4). Three subspecies are known: Speothos venaticus panamensis is found in northwestern South America and is small in size and lighter in colour;Speothos venaticus venaticus occurs in the Amazon River basin and is medium-sized and dark in colour; Speothos venaticus wingei is found in south-eastern Brazil and is light in colour and of a similar size to Speothos venaticus venaticus (4).
Found from Panama and northern South America, south to southern Brazil, Paraguay and north-eastern Argentina, and west to Bolivia, Peru and Ecuador (2), the bush dog is rare throughout this range (2).
The bush dog inhabits lowland forest, semi-deciduous forest and seasonally flooded forest, but also cerrado and wet savannahs. It is always close to water (2).
The evolutionary relationships of this unusual canid have yet to be resolved, but research has shown that it is likely to have diverged from the sister-taxon group of maned wolves (Chrysodon) three million years ago (5).
Very little is known of the behaviour of this elusive and rare species, as it has proven very difficult to find and observe in the wild. Much of what is known of this species is the result of study of captive populations and anecdotal reports of observations in the wild (4).
The bush dog tends to be active in the day, and is associated with water, with most observations of wild individuals being close to or in water courses. At night they retire to a den, which may be an abandoned armadillo nest or inside a fallen tree trunk. Bush dogs live in social groups of up to 12 members (4).
They are most often seen hunting in parties of at least two individuals, typically for large rodents including paca (Agouti paca) and agouti (Dasyprocta species) (4) (2). In more open areas, however, it seems that bush dogs hunt alone and take small rodents, teju lizards, snakes and ground-nesting birds (2). There are reports that by hunting in packs, bush dogs are able to tackle prey much larger than themselves, including capybara (Hydrochaeris hydrochaeris) (2).
Bush dogs live in extended family groups (4). One alpha female produces offspring; the oestrus cycle is suppressed in other females of the group (4). Gestation takes up to 67 days, after which a litter of one to six pups is produced, though the average litter size is 3.8 pups. The pups are suckled by their mother for around eight weeks. Non-breeding members of the group guard, carry and clean the pups (4) and males bring food to the female in the den (2). The young reach sexual maturity at one year of age. Average life-span is thought to be around ten years (2).
The threats facing this species are unclear at the present time, although it is thought that habitat encroachment may be a problem (2).
No real conservation measures have been taken, although the species is protected in most range countries. The distribution of the species needs to be re-evaluated, since there are no population estimates for any range country (2). However, the species has proven to be extremely difficult to study in the wild. Detailed field studies on diet and habitat associations are needed in order to understand the ecological and habitat requirements of the species to guide successful conservation work (2).
For further information on the bush dog see:
- IUCN/SSC Canid Specialist Group:
Authenticated (27/07/04) by Dr Claudio Sillero-Zubiri. Deputy Chair, IUCN-SSC Canid Specialist Group.
- Oestrus: the time of ovulation (release of an egg from the ovary) in female mammals, when the female becomes receptive to males, also known as ‘heat’.
- Subspecies: a population usually restricted to a geographical area that differs from other populations of the same species, but not to the extent of being classified as a separate species.
IUCN Red List (November, 2008)
- Zuercher, G.L., Swarner, M., Silveira, L. and Carrillo., O. (2004) Speothos venaticus Bush dog. In: Sillero-Zubiri, C., Hoffmann, M. and Macdonald, D.W. (Eds) Canids: Foxes, Wolves, Jackals and Dogs. Status Survey and Conservation Action Plan. IUCN/SSC Canid Specialist Group, IUCN, Gland, Switzerland and Cambridge, UK.
CITES (March, 2004)
- De Mello Beusuegel, B. and Ades, C. (1992) The behaviour of the bush dog (Speothos venaticus Lund, 1842) in the field: a review. Revista de Etologia, 4: 17 - 23.
The Digital Morphology Library. University of Texas at Austin (March, 2004)