Genetic profile of dingoes (Canis lupus dingo) and free-roaming domestic dogs (C. l. familiaris) in the Tanami Desert, Australia

Abstract

Context Many rare and endangered species are threatened by the effects of hybridisation with their domesticated and often numerically dominant relatives. However, factors that influence interactions between hybridising species are poorly understood, thus limiting our ability to develop ameliorative strategies. Aims Here, we identify family groups and investigate patterns of gene flow between dingoes (Canis lupus dingo) and domestic dogs (C. l. familiaris) in the Tanami Desert of central Australia. We aimed to determine whether human-provided resources facilitate hybridisation or alter typical patterns of dingo breeding and social behaviour. We also ask whether remote townships are arenas for dingo–dog hybridisation. Methods Tissue samples and morphological details were collected from dingo-like animals around two mine sites where humans provide abundant supplementary food and water. Using molecular DNA analyses, we assigned animals to population clusters, determined kinship and the numbers of family groups. Rates of hybridisation were assessed around the mines and in two nearby townships. Key results Of 142 samples from mine sites, ‘pure’ dingoes were identified genetically in 89% of cases. This predominance of dingoes was supported by our observations on coat colour and body morphology. Only 2 of 86 domestic dogs sampled at the two townships showed evidence of dingo ancestry. Around the mine sites, there were two distinct population clusters, including a large family group of 55 individuals around a refuse facility. Conclusions Where superabundant and consistent food, and reliable water, was available, dingo packs were much larger and co-existed with others, contrary to expectations derived from previous research. Dingo sociality and pack structures can therefore be altered where human-provided food and water are constantly available, and this could facilitate accelerated rates of hybridisation. Implications The development of appropriate domestic-waste management strategies should be a high priority in remote areas to ensure only normal rates of population increase by dingoes, and other canids more broadly. It will also potentially impede hybridisation rates if typical canid social and behavioural traits remain intact. Additionally, areas surrounding remote human settlements are likely arenas for accentuated dingo–domestic dog interactions and should be a target for future studies.

Food habits of the world's grey wolves

“…For example, the provision of human‐provided foods influences the movements, activity, dietary preferences, group sizes, and population dynamics of dingo populations in Australia (Newsome et al. , b, c, ). Grey wolves also appear commonly to take advantage of human‐provided foods; livestock and/or garbage is present in the diet of grey wolves in 66% of studies in this review.…”

High mortality and small population size prevent population recovery of a reintroduced mesopredator

“…Predator numbers are usually regulated by a density-dependent response to a shortage of resources, enabling predator and mesopredator numbers to achieve a stable state (Smith & Quinn, 1996). Generalist predators frequently take advantage of the availability of anthropogenic resources and the provision of superabundant food results in high-density predator populations (Bino et al, 2010;Newsome et al, 2013b). Generalist predators frequently take advantage of the availability of anthropogenic resources and the provision of superabundant food results in high-density predator populations (Bino et al, 2010;Newsome et al, 2013b).…”

The Effects of Food Waste on Wildlife and Humans

“…Where grey wolf populations are small and isolated, coyotes and wolves interbreed such that there are now distinct hybrid zones [30]. As in the case of dingoes [15], access to abundant food waste at focal locations could increase contact between species that can interbreed [31]. Similarly, in fragmented human-modified habitats, native species are more likely to come into contact with their domestic relatives.…”

“…Increased interactions between species at food waste sources may lead to increased hybridisation both among wild species and between wild canids and their domestic relatives [15]. For example, some species of canids can interbreed and produce fertile offspring, including coyotes (Canis latrans), grey wolves (Canis lupus), and domestic dogs (Canis familiaris).…”

“…In the case of dingoes, access to large quantities of food scraps at a waste facility resulted in decreased home-ranges and movements, larger group sizes, increased rates of inbreeding, and changes to their sociality and habitat use [14][15][16][17]. Moreover, the population of subsidised dingoes was a genetically distinct cluster, possibly because of founder effects [15]. In the case of bears, the closure of dumps in Yellowstone National Park in the 1970s led to rapidly increased grizzly bear (Ursus arctos horribilis) mortality and a more than fivefold increase in home range areas [18].…”