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is denoted V. Field data suggest that it is rare to observe higher browse availability than 100 g /m^2 , which is equivalent to ...
Scaling the wolf consumption rate to a yearly time frame yields estimates of A=12.3 moose /wolf / year and B=0.47 moose / km^2. ...
that these fluctuations will not necessarily converge on a stable limit cycle, as do consumer–resource models with only two trop ...
As we saw in Chapter 6 (see also Chapter 14), it can take many years for age dis- tributions to stabilize in long-lived organism ...
et al. 1988a) and moose in Finland (Lehtonen 1998) suggest that long-term oscilla- tions are an important feature of some large ...
repetitive, cyclic dynamics, whereas populations from more northerly latitudes exhibit repetitive cycles or perhaps even chaotic ...
feral cats, badgers, and various owls, hawks, and other raptors) in the south to a nar- row range of specialist predator species ...
densities relative to controls. The clear implication is that both bottom-up and top-down processes are important to the natural ...
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Part 2 Wildlife conservation and management ...
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13 Counting animals The trick in obtaining a usable estimate of abundance is to choose the right method. What works in some circ ...
their flocks. No arithmetic beyond adding is called for and the results are easily inter- preted. That is why total counting was ...
There are two important areas in which scientific thinking differs from everyday thinking: the selection of a random or unbiased ...
more accurate subsample surveys by helicopter to correct for visibility bias, an approach also used for counts of chicks in ospr ...
where xis an independent estimate of total numbers and Nis the number of such repeated estimates. We will first sample 1 km^2 qu ...
where fis the sampling fraction, in this case 0.333. The s(SWR) from the 1000 repeated surveys was 153 and from this we could ha ...
variation between transects is minimized and therefore that the precision of the estimate is maximized. Much the same principle ...
Statisticians do not like non-random sampling because the precision of the esti- mate cannot be calculated from a single survey. ...
Or we might count all ducks on a sample of ponds, the shoreline of the pond pro- viding a strict boundary to the sampling unit. ...
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