functional response, as describing the rates of predation in different prey density, and determining the predator efficiency, is important in the regulation of prey populations. the functional response of male and female adult of lady beetle, hippodamia variegata, was studied at different densities of green peach aphid under laboratory conditions on canola brassica napus l. (cv. rgs003). nymphs...

In this work we present a predator–prey model that incorporates individual behavior of the predators. A classical Lotka–Volterra model with self-limiting prey describes the predator–prey interaction. Predator individuals can use two behavioral tactics to dispute a prey when they meet, the classical hawk and dove tactics. Each individual can use both tactics along its life. The predator behavior...

The metabolic cost of foraging is the dark energy ecological systems. It much harder to observe and measure than its beneficial counterpart, prey consumption, yet it not inconsequential for dynamics predator populations. Here I define response as change in expenditure predators changes density. analogous intrinsically linked functional response, which consumption rate with density, they are bot...

While many studies on foraging have related energy gain to the density and the size of prey, only few have investigated whether and how habitat structure modifies the gain through affecting foraging success. In this study the influences of habitat structure and prey characteristics on the foraging success of water pipits (Anthus sp. spinoletta) were investigated experimentally. The birds take l...

We studied developmental plasticity under food stress in three female-biased size dimorphic predatory mite species, Phytoseiulus persimilis, Neoseiulus californicus, and Amblyseius andersoni. All three species prey on two-spotted spider mites but differ in the degree of adaptation to this prey. Phytoseiulus persimilis is a specialized spider mite predator, N. californicus is a generalist with a...

Invasive lionfish are assumed to significantly affect Caribbean reef fish communities. However, evidence of lionfish effects on native reef fishes is based on uncontrolled observational studies or small-scale, unrepresentative experiments, with findings ranging from no effect to large effects on prey density and richness. Moreover, whether lionfish affect populations and communities of native r...

The effects of seasonal and regional differences in diet composition on the food requirements of Steller sea lions (Eumetopias jubatus) were esti­ mated by using a bioenergetic model. The model considered differences in the energy density of the prey, and dif­ ferences in digestive efficiency and the heat increment of feeding of different diets. The model predicted that Steller sea lions in sou...

Blue jays (Cyanocitta cristata) were trained to hunt for non-cryptic moths presented in projected images. On each trial, the jays chose one of two patches to hunt in: (1) a uniform, “non-depleting” patch with constant prey density of 0.25; or (2) a “depleting” patch in which prey density changed during the foraging bout. In the depleting patch, the initial prey density was 0.50, declining to ze...

In this work we present a predator-prey model that incorporates individual behavior of the predators. A classical Lotka-Volterra model with self-limiting prey describes the predator-prey interaction. Predator individuals can use two behavioral tactics to dispute a prey when they meet, the classical hawk and dove tactics. Each individual can use both tactics along its life. The predator behavior...

where x(t) denotes the density of the prey population and y(t) the density of predators. Parameters r, K, s, Y , and m are positive constants denoting the intrinsic growth rate and the carrying capacity of the prey, the death rate of the predator in the absence of prey, the yield constant, and the maximal growth rate of the predator, respectively. The function f(x) denotes the response function...