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A fraction of the Hirta population uses an open, grassy area once occupied by people. Here the pregnant females use abandoned st ...
POPULATION REGULATION, FLUCTUATION, AND COMPETITION WITHIN SPECIES 129 0.8 0.6 0.4 0.2 0 0 50 100 150 200 250 300 Population den ...
130 Chapter 8 Box 8.1Model of the Soay sheep population on St Kilda. Threshold effects on mortality can be well described by a s ...
sheep, the precise pattern of regulation is strongly affected by age structure. The mix of age groups on any of the islands is h ...
(1971) described experiments where some areas were cleared of grouse, fertilized with nitrogen in early summer, and then were le ...
inversely related to the midwinter food. Thus competition within flocks resulted in some animals starving, and the change in num ...
sometimes called food habit studies. These in themselves do not tell us what is needed in terms of digestible dry matter, protei ...
Competition and facilitation between species 9 Species do not exist alone. They live in a community of several other species and ...
4 Both exploitation and interference competition (see Section 8.8.2) can occur between species, although interference between sp ...
dN 1 /dtis positive so that N 1 increases, and to the right it is negative and N 1 decreases as indicated by the arrows. At all ...
K 2 , which is the maximum number of species 2 that the environment can hold, is less than that necessary to drive down species ...
recorded. If competition has been operating we would expect that either the popu- lation, or reproductive rate, or growth rate o ...
increase. These results are consistent with the interpretation that there was com- petition between large and small granivorous ...
where K 1 is the carrying capacity of the environment for individuals of deermice when alone, N 1 is the number of deermice, N 2 ...
(competitive exclusion). A good example of this is seen in ground doves on New Guinea and surrounding islands (Diamond 1975). On ...
populations were not responding to the experiment. In few cases have all these con- ditions been met. Because of these difficult ...
resource spectrum use a broader range of resources because they are less abundant. Some species, for example 2, 3, and 4, overla ...
Green (1998) found complementarity in ducks along habitat and feeding beha- vior axes. He found in dabbling and diving ducks in ...
realized niche is the shallow-water reedbed. Coexistence occurs from the partition- ing of the resource (nesting habitat), and t ...
of five species of warblers within conifer trees in the northeastern USA. They varied in both height in the tree and use of inne ...
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