The effects of habitat fragmentation on the genetic structure of wild boar (Sus scrofa) population in Lithuania

Abstract

Background Wild boar (Sus scrofa) is a widely distributed ungulate whose success can be attributed to a variety of ecological features. The genetic variation and population structure of Lithuania’s wild boar population have not yet been thoroughly studied. The purposes of this study were to investigate the genetic diversity of S. scrofa and assess the effects of habitat fragmentation on the population structure of wild boar in Lithuania. A total of 96 S. scrofa individuals collected from different regions of Lithuania were genotyped using fifteen microsatellite loci. Results The microsatellite analysis of the wild boars indicated high levels of genetic diversity within the population. Microsatellite markers showed evidence of a single panmictic wild boar population in Lithuania according to STRUCTURE’s highest average likelihood, which was K = 1. This was supported by pairwise Fst values and AMOVA, which indicated no differentiation between the four sampling areas. The results of the Mantel test revealed a weak isolation by distance and geographic diversity gradients that persisted between locations. Motorway fencing and heavy traffic were not an effective barrier to wild boar movement. Conclusions There was limited evidence of population genetic structure among the wild boar, supporting the presence of a single population across the study area and indicating that there may be no barriers hindering wild boar dispersal across the landscape. The widespread wild boar population in Lithuania, the high level of genetic variation observed within subpopulations, and the low level of variation identified between subpopulations suggest migration and gene flow between locations. The results of this study should provide valuable information in future for understanding and comparing the detailed structure of wild boar population in Lithuania following the outbreak of African swine fever.

Shall the Wild Boar Pass? A Genetically Assessed Ecological Corridor in the Geneva Region

“…Even with a recent reconnection, the two hypothetic clusters would still be visible, and we would have three main types of individuals distributed along the ecological corridor: individuals from the first cluster, individuals from the second cluster, and admixed individuals due to reproduction between the two previously separated clusters. In congruence with our results, analogous studies on wild boar population structures at the landscape scale found no genetic differentiation resulting from motorway separation [29,78,79], with fencing since 2004 [29] and with >20,000 average users/day [29,78]. It was suggested that genetic clustering effects were rather due to isolation-by-distance [30], or to the species' characteristics or recolonization history [31].…”

“…Studies yield various results by using the STR genetic profiling method to uncover the effect of urbanization on the population structure of wild boars. On the one hand, it was shown that motorways in Belgium and Lithuania did not represent a significant limitation to gene flow (i.e., migration between regions with successful reproduction) [28,29]. Two studies suggest that most of clustering effects were due to characteristics and recolonization history of the species [30], or to the isolation-by-distance [31], rather than to the landscape features or the urbanization coverage.…”

Changes in the Genetic Structure of Lithuania’s Wild Boar (Sus scrofa) Population Following the Outbreak of African Swine Fever

“…The analysis of genetic diversity and the population structure of wild boars was conducted with regard to the different prevalence estimates of ASF in affected areas of the country. This study aimed to extend the previous study [ 24 ] and obtain more insight into changes in the genetic structure of the wild boar population in Lithuania following the emergence of ASF. In the previous study, in which 15 microsatellites were analysed, no evidence was found of genetic differentiation among wild boars before the ASF outbreak in Lithuania [ 24 ].…”

“…This study aimed to extend the previous study [ 24 ] and obtain more insight into changes in the genetic structure of the wild boar population in Lithuania following the emergence of ASF. In the previous study, in which 15 microsatellites were analysed, no evidence was found of genetic differentiation among wild boars before the ASF outbreak in Lithuania [ 24 ].…”

“…To limit the spread of ASF, control measures such as sanitary culling induced mortality that could contribute to the wild boar population decline [ 11 ]. Many research studies have focused on genetic analysis to understand the phylogeographic [ 12 , 13 , 14 , 15 , 16 ] and population genetic structure of the European wild boar [ 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ]. Although various studies of the wild boar’s genetic structure have been conducted, most of them have focused on the demographic history and investigations of the natural and artificial barriers.…”