life table gives the most comprehensive explanation of the survivorship, development, and reproduction of a population. the life table parameters of an aphidophagous midge, aphidoletes aphidimyza were studied on different densities (5, 10, 20, 40, 60, 80) of third instar nymphs of aphis gossypii as prey in a growth chamber (25 ± 1 °c, 70 ± 5% rh and a photoperiod of 16l: 8d h). the pre-oviposit...

predation rate is basic to any investigation of prey-predator interaction and a major component in the selection of predators for biological control. the predation rate of variegated lady beetle, hippodamia variegata (goze), fed on different densities (20, 40, 60, 80 and 100) of third instar nymphs of cotton aphid, aphis gossypii glover, was studied under laboratory conditions (25 ± 1 °c, 65 ± ...

intraguild predation (igp) occurs when one predator species consumes another predator species with whom it also competes for shared prey. we studied igp between different stages of hippodamia variegata and aphidoletes aphidimyza in absence and presence of extraguild prey (aphis gossypii) in petri dish arena. in the absence of extraguild prey all stages of h. variegata (larva1, 2, 3, 4, female a...

searching efficiency (a') (attack rate) and handling time are two major components of natural enemies’ functional response and are usually used to evaluate their effectiveness. the age-specific searching efficiency of aphidoletes aphidimyza (rondani) was studied during its larval stage. the experiment was conducted in terms of age-specific functional response to the varying density (5, 1...

searching efficiency is a key parameter of functional response which is in turn the major components in the selection of predators and parasitoids for biological control. searching efficiency of scymnus syriacus mulsant feeding on aphis craccivora koch was determined at five different experimental arenas (i.e. 195, 247, 304, 385 and 650 cm2) on broad bean (vicia fabae l.). to do this, functiona...

A predator’s per capita feeding rate on prey, or its functional response, provides a foundation for predator–prey theory. Since 1959, Holling’s prey-dependent Type II functional response, a model that is a function of prey abundance only, has served as the basis for a large literature on predator–prey theory. We present statistical evidence from 19 predator–prey systems that three predator-depe...

Predators play a key role in shaping natural ecosystems, and understanding the factors that influence a predator's kill rate is central to predicting predator-prey dynamics. While prey density has a well-established effect on predation, it is increasingly apparent that predator density also can critically influence predator kill rates. The effects of both prey and predator density on the functi...

The predation and searching efficiency of fourth instar of predatory C. septempunctata at various densities of mustard aphid, Lipaphis erysimi (Kaltenbach) and predator was investigated under laboratory conditions. The feeding rate of predatory stage decreased at increased prey- and predator densities. Highest percent (92.80%) prey consumption was observed at initial prey density and lowest per...

The density-dependent foraging response of eagle rays (Myliobatis tenuicaudatus) to infaunal bivalves (Macomona lilliana) was measured in a New Zealand sandflat. Disturbance pits provided unequivocal indicators of ray feeding activity, and pits were counted on a plot (250 m 3 500 m) which had prey density mapped in a 200 cell (25 m 3 25 m) grid. Although foraging response increased significantl...