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Bush Dog - Speothos venaticus
Bush Dog - Speothos venaticus

[Image: photo.jpg]

Common Names 
vinegar dog, savannah dog, zorrito vinagre and cachorro-do-mata 

Kingdom Animalia 
Phylum Chordata 
Class Mammalia 
Order Carnivora 
Family Canidae 
Genus Speothos 

Three subspecies are known: 
1. Speothos venaticus panamensis is found in northwestern South America and is small in size and lighter in colour; 
2. Speothos venaticus venaticus occurs in the Amazon River basin and is medium-sized and dark in colour; 
3. Speothos venaticus wingei is found in southeastern Brazil and is light in colour and of a similar size to S.v. venaticus. 

[Image: photo.jpg]

Shoulder height: 20 - 30 cm 
Head and body length: 57 - 75 cm
Head and body length: 57 - 75 cm
Weight 5 - 8 kg

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. It is adapted to a semi-aquatic life amongst the forest, and has short legs, a short bushy tail, a rounded muzzle and ears, and webbed feet. 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 throat patch that is lighter. A large range of contact calls are produced, possibly because visual communication is difficult in the forest. 

Found from Panama and northern South America to southern Brazil, Paraguay and northeastern Argentina. It reaches west to Bolivia, Peru and Ecuador. It is rare throughout this range. 

Inhabits lowland forest, semi-deciduous forest, seasonally flooded forest, but also cerrado and wet savannahs. It is always close to water. 

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.

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.

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.

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Predatory Behaviour
They are most often seen hunting in parties of at least two individuals, typically for large rodents including paca (Agouti paca) and agouti (Dasyprocta spp.). In more open areas, however, it seems that bush dogs hunt alone and take small rodents, teju lizards, snakes and ground-nesting birds. There are reports that by hunting in packs, bush dogs are able to tackle prey much larger than themselves, including capybara (Hydrochaeris hydrochaeris). 

Bush dogs live in extended family groups. One alpha female produces offspring; the oestrous cycle is suppressed in other females of the group. 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 and males bring food to the female in the den. The young reach sexual maturity at one year of age. Average life-span is thought to be around 10 years.

The threats facing this species are unclear at the present time, although it is thought that habitat encroachment may be a problem.

Classified as Vulnerable (VU C2a (i)) on the IUCN Red List 2004 and listed in Appendix I of CITES.

No real conservation measures have been taken, although the species is protected in most range countries. The distribution of the species needs to be reevaluated, since there are no population estimates for any range country. 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.

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Red Dog Wrote:Bush Dog Hunting Accounts

reddhole Wrote:Below are two hunting accounts from scientific journals. The bush dog is very difficult to observe and hunting bush dogs are rarely seen.

Single Bush Dog Attacks Large Paca

Source: Deutsch, Journal of Mammology 64 (3) P 532-533, 1983

As you can see below, a bush dog apparently chased a large paca from its burrow into a river, dragged it by its head 200 meters and fought for 30 minutes with it. I'm not sure why the bush dog suddenly abandoned the attack (perhaps scared by the observers?), but the paca was in very bad shape and had to be euthanized apparently.

The bush dog weighs about 15 lbs. and pacas typically weigh 15-30 lbs. The paca is no pushover as its quite stocky, and like many rodents has sharp incisors that can cause lots of damage.

[Image: BushDogAttacksPaca001.jpg]

[Image: BushDogAttacksPaca002.jpg]

Six Bush Dogs Attack Adult Tapir

Source: Wallace R.B., Painter RLE, Salidiania A, "An Observation of a Bush Dog (Speothos Venaticus) Hunting Behavior", Mammalia, 66, P 309-311, 2002

This account shows six bush dogs attacking an adult (perhaps 250 KG) tapir and severely wounding it after 3 hours. It appears that the bush dogs were scared off by the researchers by accident. IMHO, this is extraordinary predation as I don't think even jaguars take adult tapir that often (I could be wrong).

BTW.. The observer "A.S" is A Salidiania, one of the co-authors.

[Image: BushDogsAttackTapir001.jpg]

[Image: BushDogsAttackTapir002.jpg]

reddhole Wrote:The cortical thickness of long bones can be an effective indicator of locomotor modes and other stresses encountered by bone. Felids and canids are two carnivoran families that have similar levels of phylogenetic diversity and overlap in body size, but differ in their locomotor habits. Many canids and felids are cursorial, but felids also climb more frequently than canids. Felids also display a secondary use for their forelimbs not observed in any canids: they use their forelimbs to grasp and subdue prey. Large felids use their forelimbs much more extensively to subdue prey than do large canids and, therefore, should have proportionately greater forces applied to their forelimbs. This study uses a non-invasive radiographic approach to examine the differences in cortical thickness in the humerus between the Felidae and Canidae, as well as between size groups within these two families. Results show few significant differences between the two families, with a slight trend toward more positive allometry in the felids. Overall, radiographic measurements were found to be better predictors of body mass than either prey killing behavior or locomotor mode in these two carnivoran families. One canid that demonstrated exceptionally high cortical area was the bush dog, Speothos venaticus. The rarely observed bush dog has been postulated to swim and dig regularly, and it may be that the thickened cortical bone reflects these behaviors.

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Fantastic video of a pack of Bush Dogs in the wild 

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Red Dog Wrote:[Image: BushDogFighting1.jpg]

[Image: BushDogFighting2-1.jpg]

Red Dog Wrote:Average Bush Dog Prey Size Not That Large Due to Small Amount of Studies and Lack of Large Populations of Big Prey in Bush Dog Habitats

Bush dogs live in areas devoid of large populations of big prey. The followng study found that bush dog prey is similar in size as puma and jaguar.

[Image: BushDogPumaJaguarPreySize.jpg]

This more recent study showed that bush dogs preferred the "armored" nine-banded armadillo, averaging 5-10 KG, over agouti.

[Image: BushDogPredationonArmadillo.jpg]

IMHO, morphology trumps ecology, especially from limited studies, since morphology gives us the range of possible ecologal roles a predator can fullfill.

Red Dog Wrote:This study with a sample of 12 bush dogs shows a maximum zygomatic wdith of about 87 mm.

[Image: BushDogSkullMeasurements.jpg]

pars Wrote:From:

Food Primarily carnivorous, bush dogs are most
commonly observed hunting large rodents such as paca
(Agouti paca) and agouti (Dasyprocta spp.) (53.1% and
28.1%, respectively,
of reported sightings in central western
Amazonia; Peres 1991). Their diet may also include small
mammals (i.e., rats, Oryzomys spp. and Proechimys spp.,
rabbits, Sylvilagus brasiliensis, opossums, Didelphis spp.
and nine-banded armadillo
Dasypus novemcinctus; Van
Humbeck and Perez 1998; Zuercher and Villalba 2002).
Other prey items include teju lizards (M. Swarner pers.
obs.), snakes, and possibly ground-nesting birds. Local
people report that bush dogs can take prey considerably
larger than themselves such as capybaras (Hydrochaeris
hydrochaeris), and rheas (Rhea americana), as well as deer
(Mazama spp.), and possibly even tapir
(Tapirus terrestris)
(R. Wallace pers. comm.) by hunting in packs (Deutsch
1983; Peres 1991; Strahl et al. 1992). Their diet is reported
to vary seasonally.
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  • Shenzi
Odor that smells like blood: Single component powerful trigger for large carnivores

Date: November 10, 2014
Source: Linköping University
People find the smell of blood unpleasant, but for predatory animals it means food. When behavioral researchers wanted to find out which substances of blood trigger behavioral reactions, they got some unexpected results.

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African wild dogs compete for a log impregnated with blood or a single component. Both were equally attractive.

People find the smell of blood unpleasant, but for predatory animals it means food. When behavioural researchers at Linköping University in Sweden wanted to find out which substances of blood trigger behavioural reactions, they got some unexpected results.
Matthias Laska is professor of zoology, specialising in the sense of smell. For some time his focus has been on scents that directly affect the behaviour of animals.
"For predators, food scents are particularly attractive, and much of this has to do with blood. We wanted to find out which chemical components create the scent of blood," he says.
The study, conducted at Kolmården Wildlife Park, found that for the animals, one particular component of blood odour was just as engaging as the blood odour itself.
"It's a completely new discovery that raises interesting questions on evolution," says Prof Laska.
The study has been published in the scientific journal PLOS ONE.
When Prof Laska did a search for the contents of volatile substances in mammalian blood, he found nothing. Human blood has been analysed for disease markers, but we have very little information on the substances that give blood its characteristic scent.
A master's student was sent to Friedrich-Alexander-Universität in Erlangen Germany, to analyse mammalian blood with the help of gas chromatography and mass spectrometry, methods used for separating and identifying chemical compounds in a sample. The machine detected some 30 substances, of which some are decomposition products from fats. But the machine lost the job to the human scent experts who had also been engaged. They identified scents that the gas chromatograph missed completely.
One substance stood out: an aldehyde called trans-4,5-epoxy-(E)-2-decenal, which emits the typical metallic scent that humans associate with blood.
Once the researchers had identified a scent candidate that the predators should be attracted to, they wanted to test whether the predators were actually attracted to it in reality. So they designed a study to be conducted at Kolmården Wildlife Park, involving four predator species. How would the four predators -- Asian wild dogs, African wild dogs, South American bush dogs and Siberian tigers -- react when they caught a whiff of the scent?
Half-metre long wooden logs were impregnated with four different liquids: lab-produced aldehyde, horse blood, fruit essence, and a near-odourless solvent. The animals were exposed to one scent per day in their regular enclosure, while a group of students carefully observed their behaviour.
The results were unequivocal. The logs containing aldehyde were just as attractive stimuli as those containing blood, while the two other logs aroused little interest. The commonest behaviours were sniffing, licking, biting, pawing and toying. The tiger was the most persistent, while the South American bush dogs lost interest more quickly than the other species.
The study is the first to show that a single component can be just as attractive as the complex odour.
"How this has developed through evolution is an interesting question. Perhaps there is a common denominator for all mammalian blood," says Prof Laska.
He has plans for several follow-ups of the study, including how prey animals such as mice react to blood odour.
For the wildlife park, the study provided results that can be used in its daily operations. Animals in captivity require stimulation, so as not to deteriorate or become fat. The odourised logs can be a popular addition to the animal's environment.

Journal Reference:
Sara Nilsson, Johanna Sjöberg, Mats Amundin, Constanze Hartmann, Andrea Buettner, Matthias Laska. Behavioral Responses to Mammalian Blood Odor and a Blood Odor Component in Four Species of Large Carnivores. PLoS ONE, 2014; 9 (11): e112694 DOI: 10.1371/journal.pone.0112694

Only little is known about whether single volatile compounds are as efficient in eliciting behavioral responses in animals as the whole complex mixture of a behaviorally relevant odor. Recent studies analysing the composition of volatiles in mammalian blood, an important prey-associated odor stimulus for predators, found the odorant trans-4,5-epoxy-(E)-2-decenal to evoke a typical “metallic, blood-like” odor quality in humans. We therefore assessed the behavior of captive Asian wild dogs (Cuon alpinus), African wild dogs (Lycaon pictus), South American bush dogs (Speothos venaticus), and Siberian tigers (Panthera tigris altaica) when presented with wooden logs that were impregnated either with mammalian blood or with the blood odor component trans-4,5-epoxy-(E)-2-decenal, and compared it to their behavior towards a fruity odor (iso-pentyl acetate) and a near-odorless solvent (diethyl phthalate) as control. We found that all four species displayed significantly more interactions with the odorized wooden logs such as sniffing, licking, biting, pawing, and toying, when they were impregnated with the two prey-associated odors compared to the two non-prey-associated odors. Most importantly, no significant differences were found in the number of interactions with the wooden logs impregnated with mammalian blood and the blood odor component in any of the four species. Only one of the four species, the South American bush dogs, displayed a significant decrease in the number of interactions with the odorized logs across the five sessions performed per odor stimulus. Taken together, the results demonstrate that a single blood odor component can be as efficient in eliciting behavioral responses in large carnivores as the odor of real blood, suggesting that trans-4,5-epoxy-(E)-2-decenal may be perceived by predators as a “character impact compound” of mammalian blood odor. Further, the results suggest that odorized wooden logs are a suitable manner of environmental enrichment for captive carnivores.

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Photos show elusive bush dog to be widespread in Panama

Date: January 19, 2016
Source: Smithsonian Tropical Research Institute
New camera trap photos capture the elusive bush dog in Panama on its way North as it expands out of South America. Bush dogs, Speothos venaticus, are short-legged and stubby, standing only about a foot tall at the shoulder. They live mainly in tropical forests but have also been recorded in fragmented and altered habitats. Hunting in packs of up to 10 animals, bush dogs give high-pitched whines to maintain contact and yap like puppies when they chase their prey.

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Camera trap photo of bush dogs in the wet tropical forests of Pirre, Darién Province, Panama, March 20, 2015 at 09:44h.
Credit: Provided by Ricardo Moreno, GEMAS Panamá , Fundación Natura, Fondo Darién, Fundación Yaguará Panamá, Southern Illinois University.

The bush dog is one of the most enigmatic of the world's canid species, seldom seen throughout its range in Central and South America. New data from photos taken by automated camera traps in remote areas in Panama, along with other sightings, show the species to be widespread in the country. The new study, co-authored by Smithsonian Research Associate Ricardo Moreno, will assist conservation planning for this near-threatened species.

"Our group of biologists from Yaguará Panama and collaborators are working on an article about big mammals using camera trapping data that spans Panama from the Costa Rican border to the Colombian border," Moreno said. "The bush dog is one of the rarest species that we photograph."

Bush dogs, Speothos venaticus, are short-legged and stubby, standing only about a foot tall at the shoulder. They live mainly in tropical forests but have also been recorded in fragmented and altered habitats. Hunting in packs of up to 10 animals, bush dogs give high-pitched whines to maintain contact and yap like puppies when they chase their prey. They feed mostly on large forest rodents like agoutis and pacas, but at one site in Brazil, they mainly ate armadillos. Fierce for their size, a pack of six once was seen chasing a tapir, an animal almost 20 times a bush dog's weight. Although active by day, bush dogs are remarkably hard to see and are very rarely reported even where they are known to occur.

Digital camera traps, which take pictures automatically when their infrared sensors detect an animal's body heat, are used in many wildlife studies. Camera traps were set out as part of surveys for other mammals, including jaguars. The cameras fortuitously snapped photos of bush dogs at four sites ranging from Cerro Pirre near the Colombian border in eastern Panama, to Santa Fe National Park in the western part of the country. To give some idea of the difficulty of studying the species, photos were obtained on only 11 occasions out of more than almost 32,000 camera-days (the number of cameras multiplied by the number of days they were in operation).

The article reports bush dog sightings from five additional sites, including Fortuna west of Santa Fe, showing the species is found in suitable habitat nearly throughout Panama. Panama is the only country in Central America where the species is known to occur, aside from a few unconfirmed sightings in easternmost Costa Rica near the Panamanian border. "We think that it will soon cross the border into Costa Rica," Moreno said.

The International Union for Conservation of Nature has estimated that bush dog populations have declined by up to 25 percent in the past 12 years, and has classified it as "near-threatened" globally. Unlike other some other carnivores in Panama, such as jaguar, puma and coyote, bush dogs do not appear to be directly persecuted by humans. The main threats are habitat loss and encroachment--15 percent of Panama's forests were lost between 1990 and 2010. Bush dogs have very large home ranges for animals of their size, as much as 270 square miles, and they may require large tracts of forest to survive. Other threats include reduction of the abundance of their prey from hunting by humans and exposure to diseases carried by dogs used by hunters.

Story Source: Smithsonian Tropical Research Institute. "Photos show elusive bush dog to be widespread in Panama." ScienceDaily. (accessed January 22, 2016).

Journal Reference:
Meyer, N., Moreno, R., Valdes, S., Méndez-Carvajal, P., Brown, E. and Ortega, J. New records of bush dog in Panama. Canid Biology & Conservation, 18(10): 36-40

The detailed distribution of bush dog Speothos venaticus in Panama remains unclear. We present several new records across Panama resulting from camera-trapping surveys and direct observations. Camera-trap photos taken for the first time in Panama in 2012 and 2015, together with the new sightings, confirm the species’ broad and continuous distribution along the Panamanian Isthmus. Our data reveal the importance of the region for bush dogs, but given the rapid depletion of forest habitat and the decline of prey species, emphasis should now be placed on developing quantitative indicators for evaluating population trends across Panama. Moreover, conservation measures based on ecological information in the tropical forest should be taken to enable the long-term persistence of the species in Panama. 
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  • Claudiu Constantin Nicolaescu, Shenzi
Diet of bush dogs Speothos venaticus in the
Interior Atlantic Forest of eastern Paraguay

Eleven faecal samples originating from bush dogs
were collected from the Reserve and positively identifiedby molecular analyses (Zuercher et al., 2003). Six of these contained food remains from multiple sources and the remaining five contained remains from a single food item. Vertebrate prey represented 17 of 19 identified food items and mammalian prey comprised the largest portion. Small mammals were numerically the most common mammal prey, followed by agouti and paca. No other mammal prey was detected. Avian prey, exclusively tinamous (Crypturellus tataupa), represented the next most common food item, followed by reptiles, terrestrial invertebrates, and Cecropia fruit, which all occurred equally. Mean vertebrate prey weight was 2.2 kg.
Our examination of bush dog faeces revealed a diet
consisting largely of vertebrate prey, supporting the idea of hypercarnivory by the species (Van Valkenburgh, 1991). Although paca and agouti represented only 37% of identified food items, they constituted c. 91% of the vertebrate biomass eaten. That these species were the most important contributor, in terms of biomass, to bush dog diets in the Reserve agrees with reports that caviomorph rodents are primary food sources for bush dogs (Peres, 1991).
Despite the common occurrence of small mammals
in the diet, they contributed little to total vertebrate
biomass consumed. Consumption of fruit by bush dogs has not been previously documented, and the presence of Cecropia suggests bush dogs may take advantage of seasonally available fruits. This could, however, be an opportunistic or incidental event, as also reported for neotropical felids (Oliveira, 1994).

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Food habits bush dog in Perú, according to stool samples taken by Rolando Aquino and Pablo Puertas.

Stools under microscopic examination found in the transects and in the near its burrow contained abundant bristles, remains of feathers and small splinters of bones.
Among the sows, for the particular characteristics they presented (size, coloration, layout of the bands and texture), some corresponded to Nasua nasua and Dasyprocta fuliginosa. Others that were smaller, probably belonged to Myoprocta pratti and Proechimy spp. Regarding the remains of feathers, by the grayish coloration, it is very likely that they correspond to Partridges.
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