Intrinsic Rate of Increase for a Brushtail Possum Population in Rata/kamahi Forest, Westland
نویسندگان
چکیده
An estimate of intrinsic rate of increase (rm) of a brushtail possum (Trichosurus vulpecula) population was calculated from the measured increase in possum numbers after a poisoning operation in Westland rata/kamahi forest. Our empirical estimate of rm (0.220.25) was lower than published estimates for this species (0.30, 0.34, 0.59). Consequently, the control operation was effective for longer than predicted by population models that used these published values. We suggest reasons why the rates of fecundity and juvenile survival used in other modelling studies may have been inappropriate for this population.
منابع مشابه
The Effect of Control of Brushtail Possums (trichosurus Vulpecula) on Condition of a Southern Rata/kamahi (metrosideros Umbellata/weinmannia Racemosa) Forest Canopy in Westland, New Zealand
Brushtail possums began colonising a rata/kamahi forest in the Taramakau catchment, Westland, about 1950 and by 1973 had caused widespread conspicuous canopy defoliation. They were poisoned in one block of this forest in 1970, at about the time they reached peak density, and again in 1974. In an adjacent block they were poisoned in 1974 only. A survey of forest canopy condition in 1985 showed t...
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