Since the gray wolf (Canis lupus) was removed from the list of game animals and placed under strict protection, the number of these predators in Poland has increased significantly. As far as the preservation of biodiversity is concerned, this is a desirable phenomenon, but one should not lose sight of the increasingly frequent attacks of this large predator on livestock, companion animals, and even humans. The natural predation pressure by wolves on populations of various animal species often occurs on breeding farms. Therefore, the aim of the study was to analyze wolf attacks on farmed deer on the basis of data from the Research Station of the Institute of Parasitology of the Polish Academy of Sciences in Kosewo Górne. The documentation included corpse inspection reports prepared by a veterinarian and photographs showing wolf attacks. On that deer farm, wolves made eight
attacks on fallow deer (Dama dama) between July and November 2018 and seven attacks on sika deer (Cervus nippon) between April and July 2019. In two years, a total of 51 animals (18 sika deer and 33 fallow deer) were killed. Wolves selected mostly hinds and fawns, which were most numerous, while stags accounted for a small percentage of victims, and most of them were young individuals up to 2 years of age. Wolves consumed their prey only partially, i.e. no more than 1 to 10 kg of the carcass. Excessive killing, although not very common, also occurs on other deer farms. Predators attack mainly juveniles. Methods used to protect the deer on the farm from wolf attacks were ineffective.