DogsCanis familiarisas carnivores: their role and function in intraguild competition

Abstract

1. Dogs Canis familiaris are the world's most common carnivore and are known to interact with wildlife as predators, prey, competitors, and disease reservoirs or vectors. 2. Despite these varied roles in the community, the interaction of dogs with sympatric wild carnivore species is poorly understood. We review how dogs have been classified in the literature, and illustrate how the location and ranging behaviour of dogs are important factors in predicting their interactions with wild prey and carnivores. 3. We detail evidence of dogs as intraguild competitors with sympatric carnivores in the context of exploitative, interference and apparent competition. 4. Dogs can have localized impacts on prey populations, but in general they are not exploitative competitors with carnivores. Rather, most dog populations are highly dependent on human-derived food and gain a relatively small proportion of their diet from wild prey. However, because of human-derived food subsidies, dogs can occur at high population densities and thus could potentially outcompete native carnivores, especially when prey is limited. 5. Dogs can be effective interference competitors, especially with medium-sized and small carnivores. Dogs may fill the role of an interactive medium-sized canid within the carnivore community, especially in areas where the native large carnivore community is depauperate. 6. Dogs can also be reservoirs of pathogens, because most populations around the world are free-ranging and unvaccinated. Diseases such as rabies and canine distemper have resulted in severe population declines in several endangered carnivores coexisting with high-density dog populations. Dogs can therefore be viewed as pathogen-mediated apparent competitors, capable of facilitating large-scale population declines in carnivores. 7. Based on this information, we propose conceptual models that use dog population size and ranging patterns to predict the potential for dogs to be intraguild competitors. We discuss how interactions between dogs and carnivores might influence native carnivore communities.

Gastrointestinal parasites of maned wolf (Chrysocyon brachyurus, Illiger 1815) in a suburban area in southeastern Brazil

“…The high number of domestic dogs inside this area may interfere in the dynamics of biological communities and can also spread diseases to other wildlife species (Vanak and Gompper, 2009;Paschoal et al, 2012;Hughes and Macdonald, 2013).…”

Domestic Dog Invasion in an Agroforestry Mosaic in Southern Bahia, Brazil

“…Thus, the higher number of records of dogs in agroforests than in native forests in the study region [16] results mainly from the entrance of a larger number of dogs, rather than from more frequent visits by the same individuals. The higher the number of individuals, the larger the probability of disease transmission to wild animals, adding to the expected negative effects of competition and predation by dogs [34,35,62,63]. Given that the number of people entering managed systems such as agroforests is much higher than in unmanaged native forests, the higher number of dogs in this agricultural system may be simply linked to the behavior of dogs following their owners to work [43].…”

Barking up the right tree: Understanding local attitudes towards dogs in villages surrounding Ranomafana National Park, Madagascar can benefit applied conservation

“…Exotic carnivores, particularly feral and/or domestic dogs represent a serious threat to wildlife worldwide given their ability to act as predators, disease vectors, and to influence trophic dynamics (Barcala 2009, Vanak and Gompper 2009, Young et al 2011, Weston and Stankowich 2013, Ritchie et al 2014, Farris et al 2015a. Recent research in Madagascar has highlighted the ability of these exotic carnivores to negatively affect native wildlife, including altering temporal activity patterns (Gerber et al 2012a, Farris et al 2015b) and spatial distribution (Farris et al 2015c) and reducing the probability of occupancy and detection for native carnivores (Gerber et al 2012b, Farris et al 2015b).…”

“…Dogs may pose a great threat to Madagascar's endemic primates as dog owners use dogs for hunting wildlife, and free-roaming and feral dogs may venture into the forest to hunt on their own. Dogs also threaten lemurs through competition interference, and may transfer zoonotic diseases to endemic primates (Butler and du Toit 2002, Butler et al 2004, Manor and Saltz 2004, Galetti and Sazima 2006, Lenth et al 2008, Lacerda et al 2009, Vanak and Gompper 2009, Young et al 2011. While many dogs that enter Madagascar's forests can be considered to be feral, i.e., unowned and unhabituated to humans, many others are owned by individuals, but are not restrained.…”