Kinship analysis reveals low dispersal in a hog deer (Axis porcinus) population in Wilsons Promontory National Park, Australia

Abstract

Context A wild population of non-native hog deer has established in the Gippsland region of Victoria, Australia, and there is particular concern about its impact on native vegetation in Wilsons Promontory National Park (WPNP). Since 2015, there has been annual culling of hog deer at WPNP to reduce deer abundances and impacts. Aims The aims of this study were to use a kinship approach based on genotyping to assess contemporary dispersal of hog deer across WPNP, by identifying close kin, to determine whether dispersal of deer into culled sites from unculled sites may affect the long-term success of management there. Differences in the dispersal of male and female hog deer were also investigated. Methods In total, 91 hog deer tissue samples were collected across WPNP and surrounding sites. Single nucleotide polymorphism (SNP) markers were sequenced, and a final dataset comprising 8275 SNPs was used for analysis. First-order, second-order, and intermediate relative pairs were identified, and the geographic distance between these pairs was assessed to determine inter-pair distances to infer dispersal. Spatial autocorrelation between male and female samples was evaluated to measure the effects of sex-biased dispersal. Key results Only seven second-order relative pairs were found across different sites, with a 30 km distance between the furthest pair observed. However, most inter-pair distances across sites were ~5–10 km. Analyses of sex-biased dispersal showed that movement by deer was not strongly influenced by one sex. Conclusions Although hog deer in WPNP are genetically similar, most relatives that were sampled were not widely dispersed. This suggests that there is limited dispersal of hog deer across this park. Implications Recolonisation of hog deer at culled sites via dispersal is likely to be infrequent in WPNP. Kinship analysis provides an effective method of assessing contemporary dispersal and could be applied to other species to assess fine-scale movement across landscapes.