This species occurs from extreme eastern Central America and northern South America, south to Paraguay and north-eastern Argentina. Isolated subpopulations may also still occur in Ecuador and Colombia, west of the Andes. Its historical distribution may have extended as far north as Costa Rica (Rosa and Nocke 2002), where the species may still survive. The current distribution map was generated using the results of an extensive survey of carnivore biologists and literature for species presence (n = 399 historic locations), as well as a bioclimatic model predicting suitable area for the species (DeMatteo and Loiselle 2008). The latter authors estimated that the total area predicted to be suitable for Bush Dogs is in the order of 14,445,000 kmÂ², with 77% of this occurring within the current range.
Speothos venaticus is strictly neotropical with a discontinuous range that extends from Panama to the northern limits of Argentina.
Biogeographic Regions: neotropical (Native )
- Nowak, R. 1999. Walker's Mammals of the World. Baltimore: The Johns Hopkins University Press.
- Hall, E. 1981. The Mammals of North America. New York: John Wiley & Sons.
- Thornback, J., M. Jenkins. 1982. The IUCN Mammal Red Data Book. Part 1: Threatened mammalian taxa of the Americas and the Australasian zoogeographic region (excluding Cetacea). Gland, Switzerland: IUCN.
Speothos venaticus is squat in stature with a body length of 575-750 mm, tail length of 125-150 mm, and a height of 300 mm. The head is wide, has a short rostrum, and is covered with short reddish tan fur. The fur darkens to a dark brown or black towards the tail, and a light patch is found on the underside of the throat (Nowak 1999). The tail exhibits similar fur as the main body. In addition, Speothos venaticus has webbed feet, a diploid chromosome number of 74 (Wayne), and molars of 2/2 pattern (Hall 1981). In m1 the talonid trenchant and inner cusp (metaconid) are absent (Hall 1981).
Range mass: 5 to 7 kg.
Range length: 575 to 750 mm.
- Burton, J., V. Burton. 1988. The Collins Guide to the Rare Mammals of the World. Lexington, Massachusetts: The Stephen Greene Press.
- Wayne, R. 1993. Molecular evolution of the dog family. Trends in Genetics, 9: 218-224.
Catalog Number: USNM 179046
Collection: Smithsonian Institution, National Museum of Natural History, Department of Vertebrate Zoology, Division of Mammals
Preparation: Skin; Skull
Collector(s): E. Goldman
Year Collected: 1912
Locality: Mouth Pirri, Near Head Of Rio Limon, Darien, Panama, North America
Elevation (m): 1524
- Type: Goldman, E. A. 1912 Sep 20. Smithsonian Miscellaneous Collections. 60 (2): 14.
Habitat and Ecology
Bush Dogs are reported to be a habitat generalist by indigenous peoples, within the context of occurring generally near water sources, particularly small streams, where prey densities may be higher (Zuercher et al. 2005; E.S. Lima, K.E. DeMatteo, R.S.P. Jorge, M.L.S.P. Jorge, J. Dalponte, H.S. Lima, and S. Klorfine pers. obs.; M. Swarner, pers. comm). Bush Dogs have been observed in lowland (below 1,500 m) forested habitats including primary and gallery forest (Defler 1986), semi-deciduous forest, and seasonally flooded forest (Aquino and Puertas 1997). Observations have also been recorded from cerrado habitat in Brazil (Silveira et al. 1998; Oliveira 2009, C. Brady pers. comm.) and Paraguay (Zuercher and Villalba 2002) and pampas (wet savanna) edge/riparian areas (Strahl et al. 1992, Emmons 1998). Recent reports mention Bush Dogs in three unique habitats: caatinga, chaco, and mangroves along the coast (DeMatteo and Loiselle 2008). In some cases, they have been observed several kilometers from forest habitat (Silveira et al. 1998). The species is also occasionally reported from secondary forest, ranchland (M. Swarner pers. comm.), fragmented cerrado ranchland (E.S. Lima, K.E. DeMatteo, R.S.P. Jorge, M.L.S.P. Jorge, J. Dalponte, H.S. Lima, and S. Klorfine pers. obs.; L. Silveira and A. JÃ¡como pers. comm.), disturbed areas (DeMatteo and Loiselle 2008, Oliveira 2009), and fragmented forest areas (Michalski and Peres 2005, Michalski 2010).
No habitat selection preference was found in either the Pantanal in Brazil (Lima, Jorge et al. 2009) or in the Upper ParanÃ¡ Atlantic forest - cerrado mixture in Paraguay (Zuercher et al. 2005); however, some evidence has been found suggesting a preference for intact savanna and forest habitat versus altered (cropland and pastures) for a group of Bush Dogs in partially fragmented cerrado, indicating that habitat use and preference may differ by region and availability (E.S. Lima, K.E. DeMatteo, R.S.P. Jorge, M.L.S.P. Jorge, J. Dalponte, H.S. Lima, and S. Klorfine pers. obs.). While Michalski (2010) reported an absence of Bush Dogs in fragmented areas in southern Amazonia, others studies have demonstrated strong evidence that their occurrence is likely (DeMatteo and Loiselle 2008; Oliveira 2009; E.S. Lima, K.E. DeMatteo, R.S.P. Jorge, M.L.S.P. Jorge, J. Dalponte, H.S. Lima, and S. Klorfine pers. obs.); however, the intensity of use in these areas and impact on ecological requirements is unknown. Preliminary data from the field suggest that as the degree of habitat fragmentation increases so does the area required by Bush Dogs (E.S. Lima pers. comm.); while these data are only available for the cerrado ecosystem in Brazil, it is suspected to be true for all habitat types and a reflection of a negative relationship between prey density and habitat fragmentation. A reanalysis of the Bush Dogâs historical distribution (n > 250 locations) determined that approximately one-quarter (20%) were associated with fragmented/altered habitat and the percentage of modified habitat increased when the estimate was expanded from the area needed to support a single individual to the area to that of breeding group (DeMatteo and Loiselle 2008).
The reported variation in home range size estimates is likely associated with habitat integrity and prey density: 150 kmÂ² (Upper ParanÃ¡ Atlantic Forest; Beisiegel 1999), ca. 16 kmÂ² (Beisiegel and Ades 2004), and 140 kmÂ² (Fixed Kernel 95%) for one group of Bush Dogs (n = 2â4 individuals) in cerrado (E.S. Lima, K.E. DeMatteo, R.S.P. Jorge, M.L.S.P. Jorge, J. Dalponte, H.S. Lima, and S. Klorfine, pers. obs.).
Preliminary field data supports captive studies that Bush Dogs exist in family groups with young from one or more litters (DeMatteo 2008, Michalski 2010, E.S. Lima, K.E. DeMatteo, R.S.P. Jorge, M.L.S.P. Jorge, J. Dalponte, H.S. Lima, and S. Klorfine, pers. obs.); however, solitary individuals are regularly observed in a variety of habitat types. Reproduction in the wild is aseasonal (DeMatteo 2008). The species appears to have a semi-nomadic movement pattern versus a true territory like many carnivores (DeMatteo 2008, E.S. Lima, K.E. DeMatteo, R.S.P. Jorge, M.L.S.P. Jorge, J. Dalponte, H.S. Lima, and S. Klorfine, pers. obs.) and has been recorded living in sympatry with Atelocynus microtis in Peru and Brazil (Leite Pitman, Beck et al. 2003, Michalski 2010). Estimated generation length is four years [(0.5 x reproductive length of six years) + sexual maturity at one year (in captivity; Porton et al. 1987).
Preliminary field data supports anecdotal reports of diet and the idea that Bush Dogs are highly carnivorous (Deutsch 1984, Peres 1991); however, there appears to be evidence of prey preference based on geographical region and habitat type, which is likely compounded by seasonal variability. For the Pantanal area in Brazil, the principal food item was Nine-banded Armadillo (Dasypus novemcinctus; 94%) with small mammals, Agoutis (Dasyprocta azarae), and birds occurring in smaller quantities; however, no fruit was recorded (n = 17, identified by scent and tracks; Lima, Jorge et al. 2009). For the interior Atlantic forest in Paraguay, the majority of the diet was composed of Agoutis and Paca (Cuniculus paca) with small mammals, rodents, reptiles, invertebrates, and Cecropia fruit occurring in lower amounts (n = 11, identified using mitochondrial DNA; Zuercher et al. 2005). In a successful reproduction center in southeast Brazil, where meat and fruit (banana and papaya) are available, animals eat fruit and meat in equal proportions (L. Saboia, pers. comm.). Predation of poultry has been reported to occur occasionally (DeMatteo 2008).
Speothos venaticus are found in forests and wet savannas. They are diurnal, inhabiting a den (burrow or hollow tree trunk) at night. They are semiaquatic and can "dive and swim underwater with great facility."
Habitat Regions: temperate ; tropical ; terrestrial
Terrestrial Biomes: savanna or grassland ; forest ; rainforest ; scrub forest
Bush dogs prey mainly on large rodents such as acouchis (genus Myoprocta), agoutis (genus Dasyprocta), and pacas (genus Agouti); they may also prey upon animals of larger mass, such as capybaras (Hydrochoerus hydrochaeris) and rheas (Rheidae).
Animal Foods: birds; mammals; amphibians; reptiles
Primary Diet: carnivore (Eats terrestrial vertebrates)
Life History and Behavior
Status: captivity: 10.3 years.
Status: captivity: 10.0 years.
Lifespan, longevity, and ageing
Speothos venaticus is most likely a monogamous species.
Mating System: monogamous
Captive observations have indicated that Speothos venaticus groups form dominance heirarchies and can exhibit aseasonal reproduction patterns based on social interactions (Nowak 1999). Estrus usually averages 4.1 days, but may be suppressed by these interactions. Polyestrus cycles have also been observed. Estrus reportedly does not begin prior to 10 months of age and until after the pup is separated from other females and paired with males. The average period between observed births is roughly 238 days with a gestation period of 67 days. One to six pups are born with a mean of 3.8 pups which weigh 130-190 g and nurse from 8 weeks to 5 months.
Range number of offspring: 1 to 6.
Average number of offspring: 3.8.
Range gestation period: 65 to 70 days.
Range weaning age: 28 to 150 days.
Key Reproductive Features: iteroparous ; gonochoric/gonochoristic/dioecious (sexes separate); viviparous
Average birth mass: 160 g.
Average number of offspring: 4.
Average age at sexual or reproductive maturity (male)
Sex: male: 365 days.
Average age at sexual or reproductive maturity (female)
Sex: female: 304 days.
Parental Investment: altricial
- Nowak, R. 1999. Walker's Mammals of the World. Baltimore: The Johns Hopkins University Press.
IUCN Red List Assessment
Red List Category
Red List Criteria
- 2008Near Threatened(IUCN 2008)
- 2008Near Threatened
- 1994Vulnerable(Groombridge 1994)
- 1990Vulnerable(IUCN 1990)
- 1988Vulnerable(IUCN Conservation Monitoring Centre 1988)
- 1986Vulnerable(IUCN Conservation Monitoring Centre 1986)
- 1982Vulnerable(Thornback and Jenkins 1982)
Speothos venaticus exhibit low density populations. While protected in many countries, their populations are currently diminishing due to habitat destruction. The IUCN Red List rates the species as "Vulnerable" to extinction, because it is becoming divided up into small populations that are separated by unsuitable habitat.
Bush dogs are listed in Appendix I of of the CITES, so international trade in the animals or their products is supposed to be highly regulated.
There are several captive breeding programs at zoos around the world.
US Federal List: no special status
CITES: appendix i
IUCN Red List of Threatened Species: near threatened
Despite its large distributional range and occurrence in a variety of habitats, Bush Dogs seem to be naturally rare throughout their range. In a recent survey by DeMatteo (2008), the majority of countries in the Bush Dogâs distribution reported the status of the species as rare or unknown (rare: Ecuador; rare or unknown: Argentina, Bolivia, Brazil, French Guiana, Paraguay; unknown: Panama and Venezuela) and only two countries reported it as common (Guyana and Peru). The species is seldom recorded with camera traps; however, caution should be taken when interpreting the lack of detection, as this may actually be associated with the species actively avoiding features associated with this technique (e.g., placement of traps along animal trails used by other carnivores) or assumptions on animal movement (e.g., placement along roads assumes the animal will walk along the road versus cross over the road).
Demographic data for Bush Dogs are lacking throughout their range and population estimates have been reported only for a few areas: <100 in Misiones Argentina (DeMatteo 2008), >1,000 in Bolivia (DeMatteo 2008), > 1,000 in 4,022 kmÂ² or one individual/4 kmÂ² in Cusco Peru within the Camisea River region (DeMatteo 2008), 0.04 individuals/kmÂ² (B. Beisiegel pers. comm.) in Brazil, 0.025 individuals/kmÂ² in partially fragmented cerrado in Mato Grosso Brazil (E.S. Lima, K.E. DeMatteo, R.S.P. Jorge, M.L.S.P. Jorge, J. Dalponte, H.S. Lima, and S. Klorfine, pers. obs.), 15.8 individuals/394 kmÂ² or 0.04 individuals/kmÂ² in the Pantanal in Brazil (Lima, Jorge et al. 2009), and 0.001 individuals/kmÂ² in fragmented southern Amazonia Brazil (Michalski 2010). A suitable area of approximately 11,000,000kmÂ² (DeMatteo and Loiselle 2008), and an average population density of ca. 0.01 individuals/kmÂ², would predict an estimated population of 110,000 individuals, approximately half of which would be mature; however, the effects of fragmentation, degree of protection, and variability across their broad distribution would suggest that this is an over-estimate.
Across the Bush Dogâs distribution, population trends are reported as unknown in two countries (Guyana and Panama), declining in two (Paraguay and Venezuela), unknown or stable in one (French Guiana), and stable in two (Ecuador and Peru, specifically Cusco Peru) (DeMatteo 2008). Across the entire range, increasing levels of habitat fragmentation (urbanization and agriculture), threats to prey populations with illegal poaching, and exposure to potentially lethal candid-related diseases, mean that the probability that the trend is stable or increasing is highly unlikely.
There are several serious perceived threats, including: 1) human encroachment and loss of intact habitat due to large-scale agriculture (e.g., soybean), conversion of land to pasture, and large-scale plantations of monoculture trees (e.g., eucalyptus, pine); 2) reduction in prey abundance due to illegal poaching and domestic dog predation; and 3) increased risk of contracting lethal diseases from domestic dogs (proximity to human populations and hunting dogs (DeMatteo 2008).
Canid-related diseases are a threat not previously identified for Bush Dogs. However, field evidence supports that pathogens may be transmitted by domestic dogs, and the effects can be potentially devastating, mainly due to the speciesâ group living (Mann et al. 1980, Steinel et al. 2001, Leite Pitman, Nieto et al. 2003, Jorge, Morato et al. 2007, Jorge, Nunes, et al. 2007, DeMatteo 2008, Jorge et al. 2008, E.S. Lima, K.E. DeMatteo, R.S.P. Jorge, M.L.S.P. Jorge, J. Dalponte, H.S. Lima, and S. Klorfine, pers. obs.). E.S. Lima, K.E. DeMatteo, R.S.P. Jorge, M.L.S.P. Jorge, J. Dalponte, H.S. Lima, and S. Klorfine (pers. obs.) observed this effect when a generalized hair loss, suspected to be a type of mange, gradually spread through a group of wild Bush Dogs, eventually killing all individuals. In addition to mange, parvovirus and rabies are diseases reported as negatively effecting wild populations (Mann et al. 1980, DeMatteo 2008). The species has been identified to be susceptible to both Dioctophyma renale and Amphimerus interruptus (museum collections - Vierira et al. 2008), Lagochilascaris sp. (VolcÃ¡n and Medrano 1991), and as a host for Echinococcus vogeli (Cestoda: Taeniidae) (Rausch and Bernstein 1972). Captive animals have been identified as susceptible to a variety of diseases and parasites, including parvovirus (Janssen et al. 1982), vaccine-induced canine distemper (McInnes et al. 1992), leishmania (Lima, Fattori et al. 2009), Spirocerca lupi (Rinas et al. 2009), Toxoplasma gondii (Sedlak and Bartova 2006), and Campylobacter (L. Saboia pers. comm.). With the latter, 13 of 15 individuals in a large family group suddenly died from severe haemorrhagic enteritis when they contracted Campylobacter from an infected Coati that they were inadvertently fed (L. Saboia pers. comm.). This loss of multiple animals in a short period emphasizes both the species sensitivity to various diseases and the susceptibility of group living species to pathogens. With increasing proximity to human areas and intrusion into protected areas with hunting dogs, the risk of exposure to disease is potentially high. Exposure to disease may also result from feral or semi-feral, non-vaccinated, domestic dogs that regularly hunt prey independent of humans (K. DeMatteo pers. obs.). DeMatteo (2008) noted that in Brazil more problem interactions were noted to occur between Bush Dogs and domestic dogs than with livestock, which only emphasizes the threat of disease to the species.
This species occurs in several protected areas throughout its range, but it has a patchy distribution and occurs at very low densities. Hunting is prohibited in Colombia (Law Number 848:1973), Ecuador (Law Number 74:1981), French Guiana (Law Number JO19860625:1986), Panama (Law Number 2-80:1980), Paraguay (Law Number 18796:1975) and Peru (Law Number 5056:1970). Hunting and trade is regulated in Argentina (Law Number 22.421:1981), Bolivia (Law Number 12301:1975), Brazil (Law Number 5197:191967), and Venezuela (Law Number 276:1970). There is no Information for Guyana and Suriname. Unfortunately, in many parts of its range, resources are inadequate to manage designated protected areas and enforce existing wildlife laws.
Included in CITES on Appendix I.
Bush Dogs occur in captivity and are part of a successful international breeding programme (Buck 2009), which includes Asia (Japan), Europe, Brazil, and North America. There have been no known attempts at reintroduction.
Population estimates and demographic data for Bush Dogs is still little known across its range. This extends to an understanding of the social dynamics of individual groups, especially in terms of dispersal of young and area of use relative to other groups (overlapping or separate home ranges). Habitat associations are not clearly understood â the species was once thought to be dependent on forests but is now increasingly observed in open and fragmented habitats; however there is no data on population viability in such areas. While preliminary data on diet supports a primarily carnivorous diet, seasonal changes and geographical variation in diet needs to be evaluated. Determining how the impact of disease, especially transmission dynamics from domestic dogs, can be managed or minimized in wild populations needs to be addressed. Interspecific relationships with sympatric carnivores needs to be further evaluated.
Locating evidence of species presence using standard survey techniques, including camera traps and transect surveys, has proven difficult (Beisiegel 2009, DeMatteo et al. 2009, Michalski 2010). The use of artificial scent lures, which can increase attraction to a specific location, have been unsuccessful with wild Bush Dogs (Zuercher et al. 1999). However, there are several methodological adjustments that may increase the effectiveness of these techniques with the species, including adjusting the height of camera placement, increasing trapping effort, and concurrent use of long-call vocalization playbacks and conspecific urine (DeMatteo et al. 2004). Limited field trials in partially fragmented cerrado (2004-2005) with playbacks, urine, and leg-hold traps were unsuccessful (K. DeMatteo unpubl. data). However, additional trials are needed to determine how species density, habitat variability (forest versus cerrado), and prey density alters technique effectiveness.
Preliminary and ongoing research using a combination of three non-invasive techniques (scent-detection dogs, faecal DNA screening, GIS technology) has been shown to be successful for the species (DeMatteo et al. 2009, unpubl. data) and should be expanded to additional regions and habitat. This suite of techniques eliminates the need to attract the species to a specific location and allows insight into many ecological variables including habitat use (intact and fragmented), population status, minimum area of use, and niche overlap/separation with other carnivores.
Relevance to Humans and Ecosystems
Economic Importance for Humans: Negative
The bush dog (Speothos venaticus) is a canid found in Central and South America. In spite of its extensive range, it is very rare in most areas except in Suriname; it was first identified by Peter Wilhelm Lund as fossils in Brazilian caves and believed to be extinct. The bush dog is the only living species in the genus Speothos, and genetic evidence suggests that its closest living relative is the maned wolf of central South America.
In Brazil it is called cachorro-vinagre ("vinegar dog") or cachorro-do-mato ("bush dog"). In Spanish-speaking countries it is called perro vinagre ("vinegar dog"), zorro vinagre ("vinegar fox"), perro de agua ("water dog"), or perro de monte ("bush dog").
Adult bush dogs have soft long brownish-tan fur, with a lighter reddish tinge on the head, neck and back and a bushy tail, while the underside is dark, sometimes with a lighter throat patch. Younger individuals, however, have black fur over their entire bodies. Adults typically have a head-body length 55–75 cm (22–30 in), with a 13 cm (5 in) tail. They have a shoulder height of 20–30 cm (8–12 in) and weigh 5–8 kg (11–18 lb). They have short legs relative to their body, as well as a short snout and relatively small ears.
The teeth are adapted for its carnivorous habits, and uniquely for an American canid, the dental formula is
for a total of 38 teeth. The bush dog is one of three canid species with trenchant heel dentition, having a single cusp on the talonid of the lower carnassial tooth that increases the cutting blade length. Females have four pairs of teats, and both sexes have large scent glands either side of the anus. Bush dogs have partially webbed toes, which allow them to swim more efficiently.
Distribution and habitat
Bush dogs are found from Panama in Central America, through much of South America east of the Andes, as far south as central Bolivia, Paraguay, and southern Brazil. They primarily inhabit lowland forests up to 1,900 metres (6,200 ft) elevation, wet savannas, and other habitats near rivers, but may also be found in drier cerrado and open pasture.
- Speothos venaticus venaticus - southern Colombia and Venezuela, the Guyanas, most of Brazil, eastern Ecuador and Peru, Bolivia, northern Paraguay
- Speothos venaticus panamensis - Panama, northern Colombia and Venezuela, western Ecuador
- Speothos venaticus wingei - southern Brazil and Paraguay, extreme north-eastern Argentina
Bush dogs are carnivores and hunt during the day. Their typical prey are pacas, agouti, and capybaras, all large rodents. Although they can hunt alone, bush dogs are usually found in small packs. The dogs can bring down much larger prey, including peccaries and rheas, and a pack of six dogs has even been reporting hunting a 250 kg (550 lb) tapir. When hunting paca, part of the pack chases it on land, and part wait for it in the water, where it often retreats.
Bush dogs appear to be the most gregarious South American canid species. They use hollow logs and cavities such as armadillo burrows for shelter. Packs consist of a single mated pair and their immediate kin, and have a home range of 3.8 to 10 square kilometres (1.5 to 3.9 sq mi) Only the adult pair breed, while the other members of the pack are subordinate, and help with rearing and guarding any pups. Pack-mates keep in contact with frequent whines, perhaps because visibility is poor in the undergrowth where they typically hunt. While eating large prey, parents position themselves at either ends of the animal, making it easier for the pups to disembowel it.
Bush dogs mate throughout the year; oestrus lasts up to twelve days, and occurs every 15 to 44 days. Like many other canids, bush dog mating includes a copulatory tie, during which the animals are locked together.
Gestation lasts from 65 to 83 days, and normally results in the birth of a litter of three to six pups, although larger litters of up to ten have been reported. The young are born blind and helpless, and initially weigh 125 to 190 grams (4.4 to 6.7 oz). The eyes open after fourteen to nineteen days, and the pups first emerge from the nativity den shortly thereafter. The young are weaned at around four weeks, and reach sexual maturity at one year. They live for up to ten years in captivity.
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- DeMatteo, K., Michalski, F. & Leite-Pitman, M. R. P. (2011). "Speothos venaticus". IUCN Red List of Threatened Species. Version 2011.2. International Union for Conservation of Nature. Retrieved 18 January 2012. Database entry includes justification for why this species is near threatened
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- Wayne, R.K., et al. (1997). "Molecular systematics of the Canidae". Systematic Biology 46 (4): 622–653. doi:10.1093/sysbio/46.4.622. PMID 11975336.
- "Speotheos venaticus at Arkive.org". Retrieved 2011.
- David Attenborough (November 20, 2002). The Life of Mammals, Episode 5: Meat Eaters (16:9 Stereo) (Documentary). United Kingdom: BBC/Discovery Channel. Event occurs at 17:10 min. Retrieved 2009-12-13.
- Macdonald, D.W. (1996). "Social behaviour of captive bush dogs (Speothos venaticus)". Journal of Zoology 239 (4): 525–543. doi:10.1111/j.1469-7998.1996.tb05941.x.
- Macdonald, D. (1984). The Encyclopedia of Mammals. New York: Facts on File. p. 31. ISBN 0-87196-871-1.
- Porton, I.J., et al. (1987). "Aseasonality of bush dog reproduction and the influence of social factors in the estrous cycle". Journal of Mammalogy 68 (4): 867–871. JSTOR 1381569.
- Bekoff, M., et al. (1981). "Life-history patterns and sociality in canids: body size, reproduction, and behavior". Oecologia 50 (3): 386–390. doi:10.1007/BF00344981.