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This can be compared with distributions of observed overlap in diets of desert lizards from 28 sites on three continents (Fig. 9 ...
species pairs with small overlaps than would be predicted by chance, implying that interspecific competition was causing niche s ...
Abramsky (1981) used a similar regression method to look at interspecific com- petition and habitat selection in two sympatric r ...
in density at various sites from environmental factors; there may be some factor that has been overlooked to account for the rem ...
In a test of these hypotheses Pimm and Pimm (1982) recorded the feeding choices of three nectar-feeding bird species (Himatione, ...
We should note that we do not have actual measures of the food supply in these examples, so we cannot be sure that we are seeing ...
because it produces the same changes in prey populations as would be predicted from interspecific competition (Holt 1977, 1984). ...
regenerating vegetation. This provides a habitat for African buffalo, which in turn provide short grass patches that can be used ...
that of zebra (200,000), often do not follow the zebra but take their own route and eat the long dry grass. Therefore, most migr ...
(i) a simple management program (through grazing manipulation) could be devised to control the prairie dogs, without the use of ...
If a species such as Thomson’s gazelle benefits from the grazing effects of wildebeest due to the increased productivity of the ...
It is important that we should understand the underlying concepts of interspecific competition if we are to comprehend how speci ...
buffalo. In 1961 heavy rains caused the lake levels to rise and flood the open grass- lands, a situation which remained for the ...
Thill (1984) points out the advantages for multiple use management derived from the diet partitioning. As forest practices inten ...
and shrubs formed the largest dietary component (44% browse). At this season major components for the other species were: euros, ...
10 Predation We start by describing the behavior of predators with respect to prey. With this know- ledge we explore some theore ...
3 Carnivory. This is the classical concept of predation where the predator kills and eats the animal prey. 4 Cannibalism. This i ...
moose densities go up (Gasaway et al. 1992). Other studies in Alaska and Yukon have repeated these wolf removals and show simila ...
The searching efficiency or attack rate of the predator, a, depends on the area searched per unit time, a′, and the probability ...
Na=aTsN (10.4) Substituting eqns 10.1 and 10.2 into 10.4 we get: Na=a(Tt−hNa)N (10.5) or: Na=(aTtN)/(1 +ahN) (10.6) This is Holl ...
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