Factors affecting wild boar (Sus scrofa) distribution in Uruguay

Abstract

Context

Sus scrofa is a species that easily adapts to diverse environments and climatic zones. In urban and suburban spaces, its presence negatively impacts soil, crops, and animal production, posing health risks for other animals and even humans. Declared a national pest in Uruguay, it is one of the main predators of sheep. A deeper knowledge of its habitat, current distribution, and the environmental factors that influence its locations is required to develop an adequate programme to control its population.

Aims

To determine the spatial distribution of wild boars in Uruguay and its association with environmental factors concerning livestock production, on the basis of a survey administered to farmers.

Methods

The survey was completed by 2360 farmers, gathering information on the presence of wild boars and other wildlife animals on their farms, methods used for wild boar control, economic damages caused by the species, number of sheep, and types of land-cover besides pastures (native woodlands, shelter forests, pine plantations, and eucalyptus plantations).

Key results

Farms located in the Northeast region, with native woodlands and/or pine plantations, and larger than 500 ha were more likely to report the presence of wild boars. The presence of eucalyptus plantations did not affect the presence of wild boars in any region of the country. While the presence of sheep, free- ranging dogs, or wild boars on neighbouring farms affected the presence of wild boars, the existence of eucalyptus plantations showed no effect across any region of the country. On the other hand, the presence of wild boars increased in association with the presence of pampas foxes (Lycalopex gymnocercus).

Conclusions

These results provide valuable information regarding the current distribution of an invasive exotic ungulate, and factors influencing the probability of reporting its presence.

Implications

This information will serve as a starting point for future research analysing additional ecological and farm characteristics, as well as management strategies in sheep farms aimed at detecting, evading, dissuading and/or controlling this predatory species on the basis of its behaviour and environmental preferences.