Until the year 2000, the population of Iberian wolves (Wolf) present in Galicia fed mainly on carrion from domestic animals. However, the appearance of Creutzfeldt-Jakob disease, also known as bovine spongiform encephalopathy or mad cow disease, altered the eating habits of this canid.
According to a study published inEnvironmental Management, European health regulations that prohibited abandoning dead cattle pushed wolves to attack wild boars, roe deer and wild ponies, as well as cattle farms in order to feed themselves. And it is that one of the decisive measures of the EU to face the crisis of the mad cows wasprohibit the abandonment of corpses of ruminants that died on farmsand that they constituted one of the main dishes for the wolves. The measure has also affected other scavenger species, such as the vultures of the Iberian Peninsula.
To carry out the study, a team of researchers analyzed the evolution of the diet of wolves in Galicia in two stages: from the 70s to 2000, and after the application of the aforementioned regulations. Other factors also influenced the change in habits of these canids, such as areduction in the livestock census, depopulation of rural areas and reforestation of agricultural landsthat has favored the expansion of wild ungulates, such as horses, ponies or roe deer. According to the analyzes, while in the 70s wolves fed mainly on carrion, as of 2004 their diet changed dramatically in the Galician territory, where it is now based on ungulates.
According to Felipe Bárcena, a scientist at the University of Santiago de Compostela and co-author of the work, the expansion of the roe deer and the existence in Galicia of a large population of wild ponies has softened the impact of the disappearance of the cattle carrion, which has allowed a change in the wolf’s diet and has strengthened its predator niche. For another of the authors, Laura Lagos, in the western area of Galiciawild ponies have become a prime preylike the roe deer in the eastern mountains. At the same time, while in all of Galicia sheep and goats have ceased to be fundamental in the wolf’s diet, the consumption of cattle has increased – despite the fact that their census has been reduced by 37% – and the damage to livestock vaccine.
These scientists agree that this situation aggravates the problems of coexistence between wolves and humans and negatively affects the conservation of this carnivore. For this reason, they propose the existence of an environmental management that guarantees the increase of the populations of roe deer and wild pony, together with actions to restore the habitat to provide wolves with a diverse and abundant community of wild prey, essential to ensure that the canid population overcome natural or artificial alterations of their habitat, and to reduce conflicts with livestock. In addition, the carcasses of the animals should be prevented from being removed.
