Unregulated hunting and genetic recovery from a severe population decline: the cautionary case of Bulgarian wolves

Abstract

European wolf (Canis lupus) populations have suffered extensive decline and range contraction due to anthropogenic culling. In Bulgaria, although wolves are still recovering from a severe demographic bottleneck in the 1970s, hunting is allowed with few constraints. A recent increase in hunting pressure has raised concerns regarding long-term viability. We thus carried out a comprehensive conservation genetic analysis using microsatellite and mtDNA markers. Our results showed high heterozygosity levels (0.654, SE 0.031) and weak genetic bottleneck signals, suggesting good recovery since the 1970s decline. However, we found high levels of inbreeding (F IS = 0.113, SE 0.019) and a N e /N ratio lower than expected for an undisturbed wolf population (0.11, 95 % CI 0.08-0.29). We also found evidence for hybridisation and introgression from feral dogs (C. familiaris) in 10 out of 92 wolves (9.8 %). Our results also suggest admixture between wolves and local populations of golden jackals (C. aureus), but less extensive as compared with the admixture with dogs. We detected local population structure that may be explained by fragmentation patterns during the 1970s decline and differences in local ecological characteristics, with more extensive sampling needed to assess further population substructure. We conclude that high levels of inbreeding and hybridisation with other canid species, which likely result from unregulated hunting, may compromise long-term viability of this population despite its current high genetic diversity. The existence of population subdivision warrants an assessment of whether separate management units are needed for different subpopulations. Our study highlights conservation threats for populations with growing numbers but subject to unregulated hunting.

Legal implications of range expansions in a terrestrial carnivore: the case of the golden jackal (Canis aureus) in Europe

“…Hybridization between golden jackals and wolves, already reported in Bulgaria (Moura et al 2014), may at first sight seem to be a different matter, as it does not involve domesticated or alien species. As such, it would seem to constitute an instance of natural hybridization.…”

“…In Europe, golden jackals may crossbreed with domestic dogs and with wolves (Leonard et al 2014;Moura et al 2014). From the perspective of international and EU wildlife law, a clear distinction is to be drawn between anthropogenic and natural hybridization (Allendorf et al 2001;Genovart 2009).…”

“…It has been demonstrated that the probability of hybridization among canids is affected by the stability of social groups. [On wolf culling and hybridization with jackals (and also dogs) see Moura et al (2014); for effects of social group disruption on hybridization among canids see Grant et al (2005), Rutledge et al (2010Rutledge et al ( , 2012 and Bohling and Waits (2015)]. Survival of breeding individuals is the main factor affecting pack stability, and is under strong influence of anthropogenic mortality.…”

The illegal exploitation of hog badgers (Arctonyx collaris) in China: genetic evidence exposes regional population impacts

“…Microsatellite markers can provide a powerful molecular tool for detecting genetic diversity and differentiation (Liu et al 2013;Moura et al 2014). They have been used extensively to study population variability of European (Meles meles) and Asian (M. leucurus) badgers (e.g., Pope et al 2006), but despite a close phylogenetic relationship, similar data for the hog badger are very limited (Helgen et al 2008), with no systematic genetic studies performed to date.…”

PCR-RFLP Analysis of D-Loop mtDNA in Indonesian Domestic Waterfowl

“…Molecular analysis is a high-reliability approach, combined with quantitative approaches and traditional breeding strategies for design efficiency of preservation strategy (Dovc, Kavar, Sölkner, & Achmann, 2006). The molecular marker cannot be affected by the environment and is stable (Moura et al, 2014). Several studies have shown that the use of two or more mtDNA markers will be stronger and stronger for genetic diversity analysis (Pedrosa et al, 2005).…”