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Studies on the relationship between habitat heterogeneity and animal abundance are essential for understanding what determines biodiversity. Transect-based direct observations of eight principal prey species of tiger in the Chitwan National Park (CNP) were used to determine their abundances and habitat preferences. Chital was the most abundant prey species of tiger (Panthera tigris). Each of the prey species had significantly different habitat preferences except sambar deer and chital. Habitat preference was measured using Manly’s preference index, which revealed that short grassland, mixed forest, and riverine forest were the most preferred habitats of the prey species. The results indicate that large species of deer tend to be found in more diverse habitats than small species, except muntjac. The abundance of the principal prey species of tiger was positively correlated with habitat heterogeneity. The habitat, which contributes significantly to the heterogeneity of the landscape, is grassland in large patches of forest. The ongoing increase of forest cover in the CNP has led to a reduction in the area of grassland, which may negatively affect the abundance of the prey species of tiger. Hence, it is suggested that the restoration of landscape heterogeneity is the best way to manage the habitats in the CNP.
Den sites are critical resources that ultimately influence the population dynamics of many species. Little is known about cougar den selection, even though dens likely play important roles in cougar fitness and kitten survivorship. Thus, we aimed to describe cougar den site selection in the Southern Yellowstone Ecosystem (SYE) at two scales (third- and fourth-order resource selection) and within an ecological framework that included environmental characteristics, as well as some measure of prey availability and anthropogenic landscape features. We documented 25 unique dens between 2002 and 2013, and gathered data on microsite characteristics and paired random points for 20 dens. The timing of dens was clumped in summer, with 56 % of 25 dens beginning in June or July. Unexpectedly, female cougars in our study system exhibited third-order selection for den areas in less rugged terrain, but did not exhibit selection for greater or lesser access to hunting opportunity, roads, water, or specific habitat classes, as compared with the remainder of their home ranges. Instead, our findings suggested that third-order selection for den areas was much less important than fourth-order selection: cougar den sites were characterized by high concealment and substantial protective structure. Therefore, our results provided evidence in support of land practices that promote and protect downed wood and heavy structure on forest floors—these will best provide opportunities for cougars to find suitable den sites and maintain parturition behaviors.
We investigated diet composition, habitat selection and spatial behaviour of the red fox (Vulpes vulpes) in relation to the availability of wader nests in a coastal polder area in southwest Denmark. The predatory role of the red fox in wet grassland ecosystems has profound implications for conservation status of declining populations of grassland breeding waders. However, few studies have focussed on the foraging ecology and behaviour of the red fox in these landscapes. Faecal analyses revealed that fox diet consisted of birds (43 % of prey remains / 32 % of biomass), rodents (39 % / 21 %), sheep (mainly as carrion, 14 % / 41 %) and lagomorphs (4 % / 7 %). Charadriiformes (including waders) comprised 3–12 % of prey remains throughout the year. Telemetry data and spotlight counts indicated that foxes did not select areas with high densities of breeding waders, suggesting that foxes did not target wader nests while foraging. Foxes maintained stable home ranges throughout their lives, indicating that the area sustained a permanent fox population all year round. The population densities, estimated from spotlight surveys, were 0.74 visible foxes km−2 (95 % CI; 0.34–1.61) on the preferred breeding habitat for waders and 1.21 km−2 in other open habitats such as cultivated fields. Our results indicate that red fox predation on wader nests is incidental, consistent with the notion that red foxes are generalist predators that opportunistically subsist on many prey groups.
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