Wildlife management systems face growing challenges to cope with increasingly complex interactions between wildlife populations, the environment and human activities. In this position statement, we address the most important issues characterising current ungulate conservation and management in Europe. We present some key points arising from ecological research that may be critical for a reassessment of ungulate management in the future.
Although drive counts are frequently used to estimate the size of deer populations in forests, little is known about how counting methods or the density and social organization of the deer species concerned influence the accuracy of the estimates obtained, and hence their suitability for informing management decisions. As these issues cannot readily be examined for real populations, we conducted a series of ‘virtual experiments’ in a computer simulation model to evaluate the effects of block size, proportion of forest counted, deer density, social aggregation and spatial auto-correlation on the accuracy of drive counts. Simulated populations of red and roe deer were generated on the basis of drive count data obtained from Polish commercial forests. For both deer species, count accuracy increased with increasing density, and decreased as the degree of aggregation, either demographic or spatial, within the population increased. However, the effect of density on accuracy was substantially greater than the effect of aggregation. Although improvements in accuracy could be made by reducing the size of counting blocks for low-density, aggregated populations, these were limited. Increasing the proportion of the forest counted led to greater improvements in accuracy, but the gains were limited compared with the increase in effort required. If it is necessary to estimate the deer population with a high degree of accuracy (e.g. within 10% of the true value), drive counts are likely to be inadequate whatever the deer density. However, if a lower level of accuracy (within 20% or more) is acceptable, our study suggests that at higher deer densities (more than ca. five to seven deer/100 ha) drive counts can provide reliable information on population size.
The wild population of fallow deer in Central Europe has grown considerably over the last decade. However, information on feeding habits of this alien species in relation to the indigenous red deer or roe deer, in areas of their co-occurrence, is scarce. A prevailing view maintains that their food-niches are distinct, although direct comparative studies have not been carried out. Therefore, the aim of the research was to compare the diets of fallow, red, and roe deer feeding in the same habitat. Research was based on the rumen contents of 242 animals hunted in the autumn-winter season in the forests of Southern Poland. The analyses demonstrated that fallow deer are moderate grazers in such conditions and eat more graminoids in comparison to red or roe deer (36.4% vs. 16.1% or 5.5%, respectively). On the other hand, it feeds on less browse (17.2% vs. 41.4%) or dwarf shrubs (8.4% vs. 19.0%) than red deer, and on less bramble (10.9% vs. 34.6%) or forbs (4.0% vs. 7.6%) in comparison to roe deer (P=0.05). Although the diets of the three deer species differ in terms of the proportion of each food type in their diet, overlapping of their food-niches is high (52.6%).
Spatially heterogeneous landscapes provide solutions to the forage‐safety trade‐off when animals can access risky but energetically rewarding patches, or safer but resource‐poor patches. It can be advantageous for an animal to secure access to habitat heterogeneity at a broader scale in order to be able to dynamically adjust finer scale habitat use through time. We tested the hypothesis of a forage‐safety trade‐off optimization tactic in a hunted red deer (Cervus elaphus) population following a large accidental forest fire. We used telemetry data and fitted resource selection functions at the second‐ and third‐order scales. We then integrated the order‐specific probabilities into single, all‐in‐one multi‐level layers that synthetically captured the habitat selection patterns across scales by informing landscape‐scale annual habitat selectivity with finer within‐home‐range seasonal and diel processes. At the landscape scale, red deer anchored their home‐range at the interface of the disturbed and undisturbed patches, thereby securing habitat heterogeneity. This consequently enabled them to modulate within‐home‐range habitat selection depending on the season and the time of the day. In both seasons, red deer consistently used the burnt area for cover more during the day, and foraged in the unburnt forest and open fields at night. Interestingly there were no major seasonal differences in this diel habitat selection patterns. Increased mortality risk during the hunting season did not substantially change their spatial behaviour. We conclude that year‐round avoidance of non‐lethal human disturbance is the main driver of red deer habitat use in this system.