Next of kin next door – philopatry and socio‐genetic population structure in wild boar

Abstract

Dispersal patterns can have vital consequences for the transfer of genes in a population, thus shaping its genetic make-up and structure. Genetic relationships between individuals can, in turn, affect their social behaviour and the emergent social organization of the population. Using combination of behavioural and genetic data from the wild boar Sus scrofa population in Białowieża Primeval Forest (eastern Poland), we evaluated the socio-genetic structure of wild boar groups, the spatial genetic structure of the population and dispersal patterns. We found that wild boar post-weaning movements were largely spatially limited to the vicinity of maternal range, with female boars showing a tendency to settle in the direct neighbourhood of the kin and male boars dispersing further away from the natal area. Consequently, such dispersal patterns were reflected in the kin-based social organization and the spatial genetic structure of the population, which was manifested at a spatial scale corresponding to the size of a few home ranges (<5 km). A negative relationship between geographic distance and genetic relatedness, which was particularly strong in female boars, indicated a presence of local kin clusters dominated by female boars and the importance of female philopatry in shaping the structure of wild boar population. This was confirmed by the genetic profile and composition of social groups. This study showed the role dispersal decisions can play in the emergence of the kin-based and matrilineal social system of wild boars.

Contact rates in wild boar populations: Implications for disease transmission

“…Thus, a high proportion of yearlings in the population could enhance the spread of communicable diseases. High centrality of yearlings can be explained by increased mobility of dispersing individuals, which are leaving natal groups at this age (Podgórski et al ). In a study on Belding's ground squirrels ( Urocitellus beldingi ), exploratory behavior of juvenile males contributed to increased connectivity of colonies, resulting in higher mean parasitic prevalence (VanderWaal et al ).…”

“…We classified animals into 3 categories: juveniles (<12 months), yearlings (12–24 months), and adults (>24 months). Because the marked juveniles were older than 6 months and we were mostly interested in the behavior of dispersing animals, we merged the first 2 categories into 1 (yearlings) for further analysis to cover the dispersal age (Podgórski et al ). We fitted captured animals with ear tag radio‐transmitters in BPF (Advanced Telemetry Systems, Isanti, MN, USA and Wagener Telemetrieanlagen, Cologne, Germany), MWP (Wagener Telemetrieanlagen), AdC (TXP‐R, Televilt, Lindesberg, Sweden), and radio‐collars (TXV‐10, Televilt) in AdC.…”

African Swine Fever Epidemic, Poland, 2014–2015

“…The total area of the infected region is only ≈1,500 km 2 . The slow spatial spread of ASF may be associated with the social behavior of wild boar, which has been studied quite extensively in Białowieża Primeval Forest, straddling the Poland–Belarus border ( 14 ). Wild boar show strong site fidelity, and most (≈70%) stay within 1–2 km of the center of their natal home ranges; only a relatively small percentage (5%–10%) of the population disperses from their natal range but not farther than 20–30 km.…”

Seasonal host life‐history processes fuel disease dynamics at different spatial scales

“…Wild boar biology is characterized by distinct seasonality of behaviour and limited contact between social groups (Dardaillon, ; Graves, ; Pepin et al, ; Podgórski, Scandura, & Jedrzejewska, ). Consequently, the influence of seasonal changes in contact rates between groups on the spread of diseases is often discussed but rarely reported (Beltrán‐Alcrudo et al, ; Podgórski & Smietanka, ; Rossi et al, ).…”

“…Increased infection risk in piglets is known to be characteristic for CSF infections in wild boars, but its relevance for long‐term disease persistence is discussed. Even though piglets are unlikely to play an important role in spatial spread of the CSF virus due to rare contacts with other social groups (Dardaillon, ; Graves, ; Pepin et al, ; Podgórski et al, ), they may promote local persistence by providing sufficient susceptible hosts for the pathogen to successfully sustain a transmission chain (Artois et al, ; Kern et al, ; Schulz et al, ).…”