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Lovari, S., Minder, I., Ferretti, F., Mucci, N., Randi, E., Pellizzi, B. (2013). Common and snow leopards share prey, but not habitats: competition avoidance by large predators. Journal of Zoology, 291, 127–135.
Abstract: Resource exploitation and behavioural interference underlie competition among
carnivores. Competition is reduced by specializing on different prey and/or spatiotemporal
separation, usually leading to different food habits. We predicted that
two closely related species of large cats, the endangered snow leopard and the
near-threatened common leopard, living in sympatry, would coexist through
habitat separation and exploitation of different prey species. In central Himalaya,
we assessed (2006–2010) habitat and diet overlap between these carnivores. The
snow leopard used grassland and shrubland, whereas the common leopard
selected forest. Contrary to our prediction, snow leopard and common leopard
preyed upon similar wild (Himalayan tahr, musk deer) and domestic species (Bos
spp., dogs). Dietary overlap between snow leopard and common leopard was 69%
(yearly), 76% (colder months) and 60% (warmer months). Thus, habitat separation
should be the result of other factors, most likely avoidance of interspecific
aggression. Habitat separation may not always lead to the use of different prey.
Avoidance of interspecific aggression, rather than exploitation of different
resources, could allow the coexistence of potentially competing large predators.
Namgail, T., Fox, J., & Bhatnagar, Y. V. (2004). Habitat segregation between sympatric Tibetan argali Ovis ammon hodgsoni and blue sheep Pseudois nayaur in the Indian Trans-Himalaya. Journal of Zoology, 262, 57–63.
Abstract: Tibetan argali Ovis ammon hodgsoni and blue sheep Pseudois nayaur have almost completely overlapping distributions encompassing most of the Tibetan plateau and its margins. Such a sympatric distribution of related species with similar ecological requirements implies that there is some degree of resource partitioning. This may be accomplished on the basis of habitat and/or diet separation. This study evaluated such ecological separation on the basis of physical habitat partitioning by these two sympatric ungulates in Hemis High Altitude National Park, Ladakh, India, in an area where the argali established a small new population in 1978. Such separation was tested for
on the basis of expected difference between the species in their proximity to cliffs, associated with species-specific anti-predator behaviour. Tibetan argali selected habitats away from cliffs while blue sheep selected habitats close to cliffs. Blue sheep also selected steep slopes whereas argali selected gentle slopes. The two species did not differ
in their use of habitats in terms of elevation. They did, however, differ in their use of plant communities; blue sheep selected sub-shrub and grass-dominated communities whilst argali selected forb-dominated communities. We suggest that the two species coexist in this site as a result of the differential use of habitat associated with their
species-specific anti-predator strategies.
Shrestha, R., & Wegge, P. (2008). Wild sheep and livestock in Nepal Trans-Himalaya: coexistence or competition? Environmental Conservation, 32(2), 125–136.
Abstract: Excessive grazing by livestock is claimed to displace wild ungulates in the Trans-Himalaya. This study compares the seasonal diets and habitat use of sympatric wild naur Pseudois nayaur and domestic goat Capra hircus, sheep Ovis aries and free-ranging yak Bos grunniens in north Nepal and analyses their overlap both within and across seasons. Alpinemeadow and the legumes Oxytropis and Chesneya were critical resources for all animal groups. High overlap occurred cross-seasonally when smallstock (sheep and goats) in summer used the spring and autumn ranges of naur. Relatively high total ungulate biomass (3028 kg km-2) and low recruitment of naur (56 young per 100 adult females in autumn) suggested interspecific competition. The spatio-temporal heterogeneity in composition and phenology of food plants across the steep gradient of altitude, together with rotational grazing, appears to indirectly facilitate coexistence of naur and smallstock. However, owing to high crossseasonal (inter-seasonal) overlaps, competition is likely to occur between these two groups at high stocking densities. Within seasons, naur overlapped more with free-ranging yak than with smallstock. As their habitat use and diets were most similar in winter, when both fed extensively on the same species of shrubs, naur was most likely to compete with yak during that season.