The diet of wolf–dog hybrids in Poland does not differ from that of wolves

08 05 2026

Wolf–dog hybrids in Poland eat almost the same food as wolves. Recent research shows that their diet is based mainly on wild ungulates: roe deer, fallow deer and wild boar. This means that hybrids are not only a genetic concern, but may also play a similar role in the ecosystem and compete with wolves for food.

Hybridization between wolves and dogs is one of the important challenges in wolf conservation. Interbreeding between these animals can lead to the birth of fertile hybrids and, as a result, to the introgression of domestic dog genes into wolf populations, blurring their wild gene pool. This issue became especially important after wolves were granted legal protection in Poland in 1998. Since then, the species has been recovering not only in large forest complexes, but also in mosaics of fields, villages and smaller forests, where the risk of contact with dogs is higher. It is estimated that there are around 8 million dogs in Poland, at least 138,000 of which roam freely in forests. This raised an important question: do hybrids live and hunt like wolves, or do they rely instead on easier, human-related food sources such as waste and carrion?

This question was addressed by an international team, with a leading contribution from researchers at the Faculty of Biology, University of Warsaw. The scientists studied the diet of wolf–dog hybrids by analysing the contents of their scats. Hybrids were identified on the basis of their appearance, camera-trap footage and DNA analyses. Food composition was determined from prey remains found in the scats, such as hair, bones, fragments of hooves and other remains.

The result was clear. The hybrids did not feed mainly on waste or domestic animals, but instead they preferred wild ungulates. The most important prey were roe deer, fallow deer and wild boar, while red deer and moose played a smaller role. European hare and Eurasian beaver supplemented the diet, whereas dogs and cats appeared only sporadically.

Fig. Wolf–dog hybrids and a male wolf in the Szubin Forest, central Poland. Still frame from camera-trap footage recorded by the Association for Nature “Wolf” (the photograph comes from the discussed publication: No difference in the food composition between wolf × dog hybrids and wolves in Poland, Kwiatkowska et al., 2026).

The diet of hybrids was very similar to that of wolves. In wolves from lowland forests in Poland, wild ungulates also dominated, accounting on average for 94.5 percent of consumed food biomass. Indices comparing food niches showed a very strong overlap between the diets of hybrids and wolves. Differences between hybrids and wolves from some forests were no greater than the natural differences observed among wolves living in different regions of Poland.

The authors point to several possible explanations for this similarity. First, dogs, although they often use food of anthropogenic origin, are still capable of hunting. Second, hybrids may learn hunting behaviour from wolves. In the studied cases, all analysed hybrids had wolf mitochondrial DNA, which fits a scenario in which the mother is a female wolf and the father is a dog. Such a female raises the young in the wild. If hybrids grow up in a wolf family group, they may adopt the wolves’ way of obtaining food.

The study shows that wolf–dog hybrids are not only a genetic problem. Since they eat the same food as wolves, they may occupy a similar ecological niche and use the same resources. The authors emphasize that effective wolf conservation requires reducing the risk of hybridization with dogs. This means limiting the number of free-ranging dogs and preventing them from entering wolf habitats. Without such measures, protecting the wild character of wolf populations, both genetically and ecologically, will be much more difficult.

The article “No difference in the food composition between wolf × dog hybrids and wolves in Poland” was published in Global Ecology and Conservation. The authors affiliated with the Faculty of Biology, University of Warsaw, are Dr Iga Kwiatkowska, Prof. Sabina Pierużek-Nowak, Michał Figura, MSc, and Prof. Robert W. Mysłajek. The research was funded by the National Science Centre, Poland, and the monitoring of hybrids was supported by the Association for Nature “Wolf”.

We warmly congratulate to authors publishing the article. Full article available on the link: https://doi.org/10.1016/j.gecco.2026.e04212