Patterns and models of natal dispersal in the wild boar
Prof Stefano Focardi1, Dr Barbara Franzetti2, Dr Marta Catenacci2, Dr. Francesca Ronchi3
1ISC-CNR, Sesto fiorentino , Italy, 2ISPRA, Roma, Italy, 3ISPRA, Venezia, Italy
The range shift of wildlife species is determined by artificial mechanisms (such as voluntary or accidental translocations) or natural processes, the most relevant being natal dispersal. The evolutionary importance of natal dispersal has been widely discussed and several evolutionary hypotheses have been proposed to explain such process, such as local mate competition, inbreeding avoidance and others. Comparative studies have showed that sex-biased dispersal is an usual, but non-exclusive, pattern in mammals (male-biased) and birds (female-biased). Here we presents the main results relative to the natal dispersal of wild boar (Sus scrofa) an ungulate characterised by a peculiar demographic strategy. This species has showed an impressive ability to invade new habitats worldwide and it often represents a major threat to biodiversity and a vector of disease of utmost social and economic importance, such as the African swine fever. Using a long-term CMR data set (>20 years) we showed that dispersal in wild boar appears mainly determined by social factors: if local density is low, piglets are more prone to leave and settle in high-density areas (inverse density-dependence). Dispersal distances are thus determined by the spatial distribution of suitable settling areas. Interesting the dispersal kernel is heavy-tailed and displacements are larger in males than females. Dispersal is not for free: wild boar are at higher risk to be hunted while dispersing than philopatric animals and females were found to be more vulnerable than males. The study has interesting ramificationss both for understanding of the biology of wild boar and for its management.
The range shift of wildlife species is determined by artificial mechanisms (such as voluntary or accidental translocations) or natural processes, the most relevant being natal dispersal. The evolutionary importance of natal dispersal has been widely discussed and several evolutionary hypotheses have been proposed to explain such process, such as local mate competition, inbreeding avoidance and others. Comparative studies have showed that sex-biased dispersal is an usual, but non-exclusive, pattern in mammals (male-biased) and birds (female-biased). Here we presents the main results relative to the natal dispersal of wild boar (Sus scrofa) an ungulate characterised by a peculiar demographic strategy. This species has showed an impressive ability to invade new habitats worldwide and it often represents a major threat to biodiversity and a vector of disease of utmost social and economic importance, such as the African swine fever. Using a long-term CMR data set (>20 years) we showed that dispersal in wild boar appears mainly determined by social factors: if local density is low, piglets are more prone to leave and settle in high-density areas (inverse density-dependence). Dispersal distances are thus determined by the spatial distribution of suitable settling areas. Interesting the dispersal kernel is heavy-tailed and displacements are larger in males than females. Dispersal is not for free: wild boar are at higher risk to be hunted while dispersing than philopatric animals and females were found to be more vulnerable than males. The study has interesting ramificationss both for understanding of the biology of wild boar and for its management.
Biography:
I am senior researcher at the Istitute for COmplex Systems in Florence, Italy. My interest lies in mathematical and statistical modelling of ecological and behavioural processes with special reference to the development of emergent properties of ecological systems determined by the interaction among individuals and between individuals and ecosystems. I apply mechanical statistical methods to ecology at different scales.. I am interested to using this approach to basic understanding of animal ecology but also to application to wildlife management and conservation. My research interests also include the use of camera trapping to estimate wildlife population and the movement ecology of several mammal and bird species tracked by GPS.