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We tested the widely accepted hypothesis that spotted hyaenas (Crocuta crocuta) are non-selective in their diet. The prey preference of spotted hyaena was studied in the Addo Elephant National Park (AENP), South Africa. Diet (frequency of occurrence of prey items in the diet) was quantified through the analysis of 55 scats, and compared with available prey. A combination of large- and medium-sized mammals (buffalo (Syncerus caffer), red hartebeest (Alcelaphus buselaphus) and common duiker (Sylvicapra grimmia) were the most preferred prey items. The most abundant species, warthog (Phacochoerus africanus) and kudu (Tragelaphus strepsiceros), were ignored and avoided, respectively. These results show that the assumption that hyaena prey on the most abundant available prey species may be overly simplistic. Predation patterns, such as the ones observed in AENP, may have important ramifications for less common species that are selected by hyaena in small enclosed reserves
Large mammalian carnivores place significant pressure on their prey populations and this is exacerbated within the fenced reserves of Africa. However, foraging theory predicts that diet switching by predators may mitigate this pressure. In this study, we use data collected between 2003 and 2007 from an enclosed system in the Eastern Cape Province of South Africa to examine the response of lions Panthera leo to changes in the abundance of two important prey species — kudu Tragelaphus strepsiceros and warthog Phacochoerus africanus. As the relative abundance of warthogs increased, the number of kudu kills decreased significantly, whereas warthog kills became significantly more frequent. A similar pattern was observed for lion prey preference and the switch from kudu to warthog was also reflected in a significant decrease in the mean prey mass. Our results suggest that a diet shift occurs in lions and that the change in diet is primarily in response to an increase in warthog numbers. Prey switching may promote the persistence of predator–prey systems, which is particularly important for fenced systems where natural immigration of prey is not possible. However, continued collection and analysis of long-term observational data from the multipredator, multiprey systems of Africa is required to facilitate a full understanding of predator–prey dynamics.
We examined 617 kills made by radio-tracked Eurasian lynx Lynx lynx (Linnaeus, 1758) from March 1988 to May 1998 to assess prey spectrum, preference, and food consumption rates in the Swiss Jura Mountains. Roe deer Capreolus capreolus and chamois Rupicapra rupicapra were the main prey (69 and 22%, respectively), followed by red fox Vulpes vulpes, brown hare Lepus europaeus, domestic cat Felis calus, wild cat Fclis sylvestris, marmot Marmota marmota, pine marten Martes marles, capercaillie Telrao urogallus, and badger Meles meles. Lynx fed on an ungulate prey from 1 to 7 days, depending on the prey category. The consumption rates of males, of females alone, and of females with kittens varied from 3.2 to 4.9 kg per night, with an increasing trend as the kittens grew older. Including the days when lynx had no kill (searching time) lynx consumed 2 ± 0.9 kg per night. The mean searching time was 1.5-2 days for females, depending on the season and the number of kittens, and 2.5 days for males. The mean interval between consecutive kills was 5.9 for males and 5.2 days for females, respectively. At 38% of carcasses the presence of one or several scavengers (red fox, raven Corvus corax or both) was detected, Although 69% of the kills were roe deer and only 22% chamois, we hypothesise that in the forests of the Jura Mountains chamois are more vulnerable to lynx predation than roe deer, as chamois had a slightly higher preference index (0.59) than roe deer (0.41), based on rough estimates of the two ungulate populations in the study area.
Predation by wolves Canis lupus Linnaeus, 1758 in ungulate communities in Europe, with special reference to the multi-species system of Białowieża Primeval Forest (Poland/Belarus), was assessed on the basis results of original research and literature. In historical times (post-glacial period), the geographical range of the wolf and most ungulate species in Europe decreased considerably. Community richness of ungulates and potential prey for wolves, decreased over most of the continent from 5-6 species to 2-3 species. The wolf is typically an opportunistic predator with a highly diverse diet; however, cervids are its preferred prey. Red deer Ceruus eiaphus are positively selected from ungulate communities in all localities, moose Alces alces are the major prey only where middle-sized species are scarce. Roe deer Capreolus capreolus are locally preyed on intensively, especially where they have high density, co-exist mainly with moose or wild boar Sus scrofa, and red deer is scarce or absent. Wild boar are generally avoided, except in a few locations; and European bison Bison bonasus are not preyed upon by wolves. Wolf predation contributes substantially to the total natural mortality of ungulates in Europe: 42.5% for red deer, 34.5% for moose, 25.7% for roe der, and only 16% for wild boar. Food niche breadth (B) of wolves in Europe, calculated only for the ungulates considered in this study, increases with the number of ungulate species in the community. There is also a significant rela­tionship between ungulate community breadth and food niche breadth of wolves. Food niche breadth of wolves, however, does not achieve very high values even in the richest ungulate communities. Wolves easily adapt to locally abundant food of anthropogenic origin (livestock, garbage). The level of predation on livestock may be a result of different husbandry practices (eg use of livestock guarding dogs) rather than of differences in availability of wild and domestic prey. Available data from Europe suggest that wolves likely limit density of red deer and moose in some areas. Roe deer density can be decreased locally by wolves but is limited mainly by lynx Lynx lynx. Wild boar density is more influenced by mast crops of Quercus spp. and Fagus siluatica (and to a lesser extent by snow depth) than by wolf predation.
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