SITE CHARACTERISTICS AND THE POPULATION-DYNAMICS OF THE PINE LOOPER MOTH

1. Data from 27 populations of Bupalus piniaria L. (Lepidoptera, Geome tridae) spanning a minimum of 22 years are used to estimate the parame ters of a simple difference model of the moth's population dynamics. 2 . The resulting parameter estimates are compared with the 'site charac teristics' of the forest in which each population exists. 3. The per c apita net rate of increase is found to be positively correlated with l atitude, while the shape parameter in the function describing immediat ely density-dependent mortality is inversely related to local rainfall . 4. Possible physiological and behavioural mechanisms underlying thes e correlations are discussed.