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it lies between 0.2 and 0.4. At the midpoint, 0.3, an increase or decrease of area by a factor of 10 results in a doubling or ha ...
exponent of 0.3 for islands and 0.15 for continents probably reflects the easier dis- persal between contiguous areas of land ag ...
connect isolated fragments of original eucalypt woodland in Western Australia. These corridors result in higher species richness ...
At this stage the choice of land is determined mainly by which area contains the greatest internal diversity of habitats and als ...
Whether or not the densities of mammals should be controlled artificially in a national park is a matter of some contention (Cha ...
danger of extinction. Also included are taxa that are possibly already extinct but have definitely been seen in the wild in the ...
(b) other species which must be subject to regulation in order that trade in speci- mens of certain species referred to in the a ...
19 Wildlife harvesting In this chapter we consider how to estimate an appropriate offtake for a wildlife population. It differs ...
A population can most easily be stimulated into a burst of growth by increas- ing the level of a limiting resource or, much more ...
For a population conforming to the relationship between sustained yield and popula- tion size or density given in Fig. 19.1, a s ...
martens typically defend territories, with those of males being roughly twice the size of the female territories that they overl ...
among territory-holders might escalate with increasing marten abundance. Such a mix of direct density dependence (interference c ...
Note that we have set a condition to ensure that the population never declines below zero. We use a random number generator draw ...
sustained yield is appropriate; more where year-to-year variation in weather is above average. If a constant proportion of anima ...
population size to which we apply an adjustable quota approximating a fixed pro- portion of the population. To enable direct com ...
A harvest can be controlled either by placing a quota on offtake or by controlling harvesting effort. The latter can be regulate ...
the harvesting season, the quota being adjusted according to the estimate. In addi- tion, regulation by quota is unsafe when the ...
This escapement policy is obviously safe, at least in principle. It only becomes unsafe when we are uncertain of the abundance o ...
Although fixed escapement policies have the strongest conservation potential, the high variability in harvest levels can make fi ...
Game harvesting comes in two forms: game ranching (or game farming) and game cropping. The difference is in degree rather than k ...
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