Eesti imetajad [Võrguteavik] : liikide tundmaõppimise teejuht

http://www.ester.ee/record=b4468353*es

Spatiotemporal Effects of Supplementary Feeding of Wild Boar (Sus scrofa) on Artificial Ground Nest Depredation.

Supplementary feeding of ungulates, being widely used in game management, may have unwanted consequences. Its role in agricultural damage is well-studied, but few studies have considered the potential for the practice to attract ground nest predators. Our goal was to identify the factors influencing ground nest predation in the vicinity of year-round supplementary feeding sites for wild boar and to characterise their spatiotemporal scope. We conducted two separate artificial ground nest experiments in five different hunting districts in south-eastern Estonia. The quantity of food provided and distance of a nest from the feeding site were the most important factors determining predation risk. Larger quantities of food resulted in higher predation risk, while predation risk responded in a non-linear fashion to distance from the feeding site. Although predation risk eventually decreases if supplementary feeding is ceased for at least four years, recently abandoned feeding sites still pose a high predation risk

El Diario de Pontevedra : periódico liberal: Ano XV Número 4310 - 1898 decembro 2

Capercaillie (Tetrao urogallus) and other grouse species represent conservation concerns across Europe due to their negative abundance trends. In addition to habitat deterioration, predation is considered a major factor contributing to population declines. While the role of generalist predators on grouse predation is relatively well known, the impact of the omnivorous wild boar has remained elusive. We hypothesize that wild boar is an important predator of ground-nesting birds, but has been neglected as a bird predator because traditional morphological methods underestimate the proportion of birds in wild boar diet. To distinguish between different mammalian predator species, as well as different grouse prey species, we developed a molecular method based on the analysis of mitochondrial DNA that allows accurate species identification. We collected 109 wild boar faeces at protected capercaillie leks and surrounding areas and analysed bird consumption using genetic methods and classical morphological examination. Genetic analysis revealed that the proportion of birds in wild boar faeces was significantly higher (17.3%; 4.5×) than indicated by morphological examination (3.8%). Moreover, the genetic method allowed considerably more precise taxonomic identification of consumed birds compared to morphological analysis. Our results demonstrate: (i) the value of using genetic approaches in faecal dietary analysis due to their higher sensitivity, and (ii) that wild boar is an important predator of ground-nesting birds, deserving serious consideration in conservation planning for capercaillie and other grouse

Home ranges of raccoon dogs in managed and natural areas

<div><p>Knowledge of space use is central to understand animals’ role in ecosystems. The raccoon dog <i>Nyctereutes procyonoides</i> is considered as one of the most influential alien mesopredator species in Europe, having the potential to cause loss of local biodiversity and act as a vector for zoonotic diseases. We collared 12 animals to study their home range and habitat use in two areas with different management regimes in Estonia: in a protected natural area and in an intensively managed area. From May to October raccoon dogs inhabiting the natural area had considerably smaller home ranges compared to the managed area, 193.3ha±37.3SD and 391.9ha±292.9SD, respectively. This result contradicts somewhat earlier findings in other European raccoon dog populations, where the home range sizes in natural areas in summer and autumn period have usually been larger compared to managed areas. In both study areas raccoon dogs preferred watersides, where amphibians and other semi-aquatic prey are abundant, to other habitats available in their home ranges. We also studied movements of a raccoon dog pair in the managed study area in winter period. Due to mild weather conditions during the study period, raccoon dogs changed their resting sites quite often, covering a relatively large 599 ha area from November 2012 to January 2013, indicating the absence of usual winter lethargy during the mild winters.</p></div

Sizes of 95% fixed kernel home ranges (K95) and 100% minimum convex polygon (MCP100) areas in hectares for each radio-tracked raccoon dog in Soomaa and in Ilmatsalu study area.

<p>Note that kernel home ranges were not calculated when there were less than 50 location point available for the animal.</p

Selection of models predicting depredation in the vicinity of active and abandoned wild boar feeding sites.

<p>AICc was used for model selection; the best model is in bold. Ki−number of estimated parameters for model i; ∆i(AICc) = [AICci−min(AICc)]; ωi(AICc)–AICc weights. DPR–nest fate, binomial variable (1 – nest depredated, 0 – nest survived); TYPE – type of the study plot (supplementary feeding site or control plot), AGE – time in years that has passed from abandonment of a supplementary feeding site, AGE = 0 for active feeding sites and control plots; FT – forest type (deciduous, mixed or coniferous forest); | SP – study plot locality (supplementary feeding site or control area), where | denotes the random effect; × stands for interaction</p><p>Selection of models predicting depredation in the vicinity of active and abandoned wild boar feeding sites.</p

The first experimental design (a) and the adjusted design of the second experiment (b).

<p>Rectangles denote the location of the supplementary feeding site and dots correspond to nests in the vicinity of the site.</p