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Determining ecological corridors is crucial for conservation efforts in fragmented habitats. Commonly employed least cost path (LCP) analysis relies on the underlying cost matrix. By using Ecological Niche Factor Analysis, we minimized the problems connected with subjective cost assessment or the use of presence/absence data. We used data on the wolf presence/absence in Poland to identify LCPs connecting patches of suitable wolf habitat, factors that influence patch occupancy, and compare LCPs between different genetic subpopulations. We found that a lower proportion of cities and roads surrounds the most densely populated patches. Least cost paths between areas where little dispersal takes place (i.e., leading to unpopulated patches or between different genetic subpopulations) ran through a higher proportion of roads and human settlements. They also crossed larger maximal distances over deforested areas. We propose that, apart from supplying the basis for direct conservation efforts, LCPs can be used to determine what factors might facilitate or hinder dispersal by comparing different subsets of LCPs. The methods employed can be widely applicable to gain more in-depth information on potential dispersal barriers for large carnivores.

Carnivores are often particularly sensitive to landscape fragmentation. Ecological corridors may help to connect local populations, ensuring gene flow and retaining viable meta-populations. We aimed to establish habitat suitability models for two large carnivores in Poland, the grey wolf Canis lupus Linnaeus, 1758 and the Eurasian lynx Lynx lynx Linnaeus, 1758, based on ecological niche factor analysis (ENFA). Secondly, we calculated least cost paths (LCPs) based on cost values obtained from ENFA. Thirdly, we determined structures that might act as barriers, thus diminishing the value of the corridor unless appropriate conservation measures are taken. We compared some of the results with actual dispersal data of four lynx in eastern Poland. Results indicate that both species are highly marginalised. Less habitat that is currently available in Poland is suitable for lynx than for wolves. We determined a total of 76 LCPs. Comparison of these theoretical corridors with actual dispersal routes suggests that the traits of calculated LCPs are mostly within the range of those of real routes. We highlight a variety of features that might act as barriers, such as major roads (including planned highways), urbanized areas, and large un-forested areas. We give suggestions where concerted conservation efforts (eg wildlife passages) might be particularly well-directed.

Using data from the National Wolf Census, carried out in Poland in 2000–2001, and GIS techniques we analysed habitat selection by wolvesCanis lupus Linnaeus, 1758 in uplands and mountains of southern Poland. We compared ten habitat variables and two parameters related to wolf abundance in 52 circular plots (154 km2 each) with recorded wolves and 97 randomly selected plots with no signs of wolf presence. Wolf plots were characterized by higher elevation and closer location to the state border than wolf-free plots. Furthermore, wolf plots had higher forest cover, but smaller number of villages and towns and shorter railways and roads than plots without wolves. The best model explaining wolf distribution included forest cover, number of villages, length of roads and railway lines. Compared to northern Poland, the southern part of the country offers worse habitats for wolves due to significantly denser network of settlements and transportation routes.

We studied the predator-prey relationships among wolvesCanis lupus Linnaeus, 1758, wild ungulates, and livestock in the managed mountain forests of the Western Carpathians (S Poland). Though roe deerCapreolus capreolus dominated in the community of wild ungulates and livestock was abundant within the study area, the three wolf packs preyed mainly on red deerCervus elaphus (42% of food biomass), and next on the roe deer (33%). In both species of deer, wolves preferred killing females and juveniles more frequently than expected from their respective shares in the populations. Wild boarSus scrofa made up 4% of the food biomass, in accordance with its low share in the ungulates community. Despite the easy access of wolves to numerous unprotected sheep flocks pastured on meadows among woods, livestock constituted only 3% of the wolf food biomass. Wolves preyed mostly on sheep (88%), killing on average 34 per year. Most cases of livestock depredation occurred in August –September, on pastures located most often >50 m apart from buildings. Usually, lack of proper guarding was conducive to wolf attacks.