The relationship between temperature and the functional response of Coccinella septempunctata (L.) (Coleoptera:Coccinellidae)

The foraging activities of the predators depend on environmental variables,including air temperature. in the present study,the searching behavior and maximum consumption of prey of all developmental stages of coccinella septempunctata was carried out with respect to the changing values of the air temperature. a strong relationship between two important factors of functional response instantaneous attack rate (a') and prey handling time (th) was found with respect to temperature changes. the prey intake ratio per unit time was increased with increasing temperature up to a certain level beyond which it levels off and goes down to the extent of '0'predation. the temperature range for the foraging activities falls between 10°c-40°c however,maximum prédation rates were observed between 20-23°c and 23°c-25°c the lower temperature where the foraging activities were completely ceased was between 10-12°c irrespective of prey densities available. a parabolic (curvilinear) relationship with high scale of co-relation (r2= 0.86 - 0.99 α = 0.01) (th) was found. copyright 2010 zoological society of pakistan.