Next-generation phylogeography resolves post-glacial colonization patterns in a widespread carnivore, the red fox (Vulpes vulpes), in Europe.

Carnivores tend to exhibit a lack of (or less pronounced) genetic structure at continental scales in both a geographic and temporal sense and this can confound the identification of post-glacial colonization patterns in this group. In this study we used genome-wide data (using genotyping by sequencing [GBS]) to reconstruct the phylogeographic history of a widespread carnivore, the red fox (Vulpes vulpes), by investigating broad-scale patterns of genomic variation, differentiation and admixture amongst contemporary populations in Europe. Using 15,003 single nucleotide polymorphisms (SNPs) from 524 individuals allowed us to identify the importance of refugial regions for the red fox in terms of endemism (e.g., Iberia). In addition, we tested multiple post-glacial recolonization scenarios of previously glaciated regions during the Last Glacial Maximum using an Approximate Bayesian Computation (ABC) approach that were unresolved from previous studies. This allowed us to identify the role of admixture from multiple source population post-Younger Dryas in the case of Scandinavia and ancient land-bridges in the colonization of the British Isles. A natural colonization of Ireland was deemed more likely than an ancient human-mediated introduction as has previously been proposed and potentially points to a larger mammalian community on the island in the early post-glacial period. Using genome-wide data has allowed us to tease apart broad-scale patterns of structure and diversity in a widespread carnivore in Europe that was not evident from using more limited marker sets and provides a foundation for next-generation phylogeographic studies in other non-model species.

Hunter estimates of game density as a simple and efficient source of information for population monitoring: A comparison to targeted survey methods.

Hunters in Europe gather non-survey game species population estimates to inform wildlife management, however, the quality of such estimates remains unclear. We compared estimates of game density, realized annual intrinsic growth rates, and period mean growth rates between hunter obtained data and data obtained by targeted survey methods for four species in Poland from 1960 to 2014. Raw hunter estimates were strongly positively correlated to spotlight counts of red fox (18 years of monitoring), strip counts of brown hare (21 years) and grey partridge (25 years), male call counts of partridge (24 years), and complete counts of roe deer (49 years), and not related to spotlight counts of brown hare (15 years). Realized annual intrinsic growth rates derived from hunter estimates were strongly positively related to annual intrinsic growth rates derived from strip counts of grey partridge and complete counts of roe deer, but only weakly or not related to strip counts of brown hare, spotlight counts of red fox and brown hare, and male call counts of grey partridge. The period length at which the period mean growth rates derived from hunter estimates and estimates from other methods were strongly correlated was largely variable among methods and species. In the roe deer, correlation between these variables was strong across all years, while in smaller game species the period mean growth rates based on hunter estimates and other methods had the strongest association in period lengths of 6 to 11 years. We conclude that raw hunter estimates convey largely similar information to that provided by other targeted survey methods. Hunter estimates provide a source of population data for both the retrospective and prospective analysis of game population development when more robust estimates are unavailable.

The Relationship between Hunting Methods and the Sex, Age and Body Mass of Wild Boar Sus scrofa.

Increases in the wild boar Sus scrofa population create many conflicts that must be managed, especially because hunting represents a major cause of mortality in this game species. However, hunting effort is not distributed randomly and is influenced by many factors, including hunting methods. This can be especially important in understanding the nature of hunting pressure for both theoretical (ecological and evolutionary) and applied reasons (for management purposes, especially during infectious diseases, for example, African swine fever, outbreaks). We analyzed hunting data from the survey area in Western Poland from the years 1965-2016. In this period a total of 2335 wild boar were culled using two hunting methods: by individual hunters (43.8%) and by teams of hunters (52.0%). During the study period, the number of wild boars increased significantly but in a non-linear manner. More adult males and yearlings of both sexes were shot during individual hunts; more adult females were culled during team hunting. Moreover, the body mass of culled wild boars was positively influenced by the distance to a forest and during the team hunts heavier females and males were shot. To effectively control populations of wild boars, programs to reduce the number of individuals should be better planned and ensure the maintenance of proper age- and sex structure in the wild boar population.

The Efficiency of Live-Capture Traps for the Study of Red Fox (Vulpes vulpes) Cubs: A Three-Year Study in Poland.

Safe and efficient techniques for the live capture of carnivores are limited. In this study, we identified some of the factors that could affect the success of capturing red fox cubs with live capture traps (also known as cage traps). During a three-year period, we analysed 32 captures of 25 fox cubs (1.3 captures/fox). We assessed the impact of the following factors: sex of animals, month of trapping, weather conditions recorded for each trap-night, the willingness of cubs to explore and enter cage traps, the researchers' activity around den complexes before trapping and distances to the nearest village or farm. The overall trap rate (32 captures, including recaptured cubs) and the trap rate for individual cubs (25 captures) was 11.2 cubs/100 trap-nights and 8.7/100 trap-nights, respectively. Animals other than foxes were captured only three times, thus the selectivity of the cage-trapping method was high (32/35 = 91.4%). The probability of capturing one cub per night was 70.2% (32 cubs/ 47 nights). Cubs inhabiting dens in the vicinity of human settlements were less likely to explore and enter traps. Vixens were more likely to relocate their litters if the activity of the staff setting the traps was intense at the trapping site. The success of trapping was higher during poor weather as, for example, during rain or thunderstorms. None of the trapped animals suffered any injuries. Whereas cage trapping can be an effective and safe capture method for juvenile foxes, capture efficiency is affected by the experience of the trappers and a range of other factors including weather and distance to human settlements.

Inter-specific synchrony of two contrasting ungulates: wild boar (Sus scrofa) and roe deer (Capreolus capreolus).

Very few studies on ungulates address issues of inter-specific synchrony in population responses to environmental variation such as climate. Depending on whether annual variation in performance of ungulate populations is driven by direct or indirect (trophic) interactions, very different predictions regarding the pattern of inter-specific synchrony can be derived. We compared annual autumn body mass variation in roe deer (Capreolus capreolus) and wild boar (Sus scrofa) from Poland over the period 1982-2002, and related this to variation in winter and summer climate and plant phenological development [the Normalized Difference Vegetation Index (NDVI), derived from satellites]. Roe deer fawns (approximately 1.3 kg increase from year 1982 to 2002) and yearlings both increased markedly in mass over years. There was also an increase for wild boar mass over years (approximately 4.2 kg increase for piglets from 1982 to 2002). Despite our failure to link annual body mass to spring or winter conditions or the NDVI, the body mass of roe deer and wild boar fluctuated in synchrony. As this was a field roe deer population, and since wild boar is an omnivore, we suggest this may be linked to annual variation and trends in crop structure (mainly rye). We urge future studies to take advantage of studying multiple species in order to gain further insight into processes of how climate affect ungulate populations.

Selectivity of harvesting differs between local and foreign roe deer hunters: trophy stalkers have the first shot at the right place.

Harvesting represents a major source of mortality in many deer populations. The extent to which harvesting is selective for specific traits is important in order to understand contemporary evolutionary processes. In addition, since such data are frequently used in life-history studies, it is important to know the pattern of selectivity as a source of bias. Recently, it was demonstrated that different hunting methods were selected for different weights in red deer (Cervus elaphus), but little insight was offered into why this occurs. In this study, we show that foreign trophy stalkers select for larger antlers when hunting roe deer (Capreolus capreolus) than local hunters, but that close to half of the difference in selectivity was due to foreigners hunting earlier in the season and in locations with larger males. The relationship between antler size and age was nevertheless fairly similar based on whether deer was shot by foreign or local hunters.