A Spanish researcher has analysed the preferences of wolves from the north east of the Iberian Peninsula to demonstrate that, in reality, their favourite prey are roe deer, deer and wild boar, ahead of domestic ruminants (sheep, goats, cows and horses).
Wolves (Canis lupus) have been pursued by humans for centuries due to their supposed "addiction" to livestock. However, the study by Isabel Barja, sole author and researcher at the Universidad Autónoma de Madrid [Autonomous University of Madrid], demonstrates that in the Macizo Central Orensano [mountain range in the Ourense region] (Galicia) wolves prefer wild hoofed animals to livestock in spite of the latter being available in the study area.
The researcher, who identified the food type of wolves through their faeces, emphasises to SINC that "in 87.1% of cases the carcasses of wild hoofed animals appeared, while domestic animals were only found in 11.3%, and, to a lesser extent, the remains of carnivorous animals, such as badgers, dogs, cats and rabbits were found".
The study, which has recently been published in Wildlife Biology, reflects how roe deer are the main prey, consumed during all seasons of the year and particularly during the summer (52%) and spring (26.2%). Analysis of 593 wolf excrement samples, collected between May 1998 and October 2002, revealed that 62.8% of prey was roe deer (Capreolus capreolus), 12.6% deer (Cervus elaphus) and 10% wild boar (Sus scrofa). The consumption of domestic sheep and goats only represented 7.7% and 2.9%, respectively.
The fact that livestock remains are present in excrement samples of wolves is justified by their scavenging activity in the studied area. "Furthermore, while the study was being conducted, no attacks on livestock herds were reported", the biologist states.
One of the most important aspects to emerge from the analysis of the diet of wolves is that consumption of wild and domestic hoofed animals does not depend on their availability, that is, the abundance of prey species. The wolf prefers roe deer, deer and wild boar ahead of livestock, "in spite of the fact that both food types can be found in large quantities", Barja adds.
The results of the study confirm that wolves do not feed on the most easily captured prey, such as domestic hoofed animals; rather they prefer to consume wild animals. It would, however, be inaccurate to categorise the wolf as an opportunist species in the study area.
"In areas with a low density and diversity of wild hoofed animals where wolves feed on domestic animals, an increase in the number of wild prey, livestock vigilance and limited access to carcasses could force wolves to specialise in the consumption of wild prey and transmit this behaviour to their offspring. Without doubt, this would help to minimise conflict between humans and wolves, and would support the conservation of canidae", the researcher concludes.
Barja, Isabel. "Prey and prey-age preference by the Iberian wolf Canis lupus signatus in a multiple-prey ecosystem" Wildlife Biology 15(2): 147-154, junio de 2009.