Is the classical predator-prey theory inherently pathological? Defenders of the theory are losing grounds in the debate. We will demonstrate that the detractors’ argument is based on a faulty model, and the conceptual and predictive bases of the theory are fundamentally sound. Biological control is to introduce natural predators or parasites to ecosystems for pest control. It works when the pes...

A molecular approach, using aphid-specific monoclonal antibodies, was used to test the hypothesis that alternative prey can affect predation on aphids by linyphiid spiders. These spiders locate their webs in cereal crops within microsites where prey density is high. Previous work demonstrated that of two subfamilies of Linyphiidae, one, the Linyphiinae, is web-dependent and makes its webs at si...

We investigate the stochastic dynamics of a prey-predator type ecosystem with time delay and the discrete random environmental fluctuations. In this model, the delay effect is represented by a time delay parameter and the effect of the environmental randomness is modeled as Poisson white noise. The stochastic averaging method and the perturbation method are applied to calculate the approximate ...

The Ideal Free Distribution theory predicts a close spatial match between predators and prey. Studies have shown that seabird and prey distribution seldom conforms with this prediction. In this study, I review recent theoretical advances in spatial predator–prey interactions and relate these with studies of seabirds and pelagic schooling fish and crustaceans. Studies on seabirds and prey have g...

In the diet of raptors the presence of prey-species is influenced by their abundance and the ground-level vegetation in territories, this situation being analysed for the Bonelli s eagle (Hieraaetus fasciatus) in south-eastern Spain. First, the minimum number of prey-items for the reliability of results was tested, obtaining between 15 and 30 prey-items depending of pair. Second, differences in...

21 The effects of prey density (0.1, 1 and 10 rotifer ml ) on feeding, oxygen uptake, growth, survival and energetic efficiencies in Sparus aurata larvae were investigated. Dry weights and 21 total lengths at day 15 after hatching were similar in larvae fed with 10 and 1 rotifer ml but 21 were significantly higher than in larvae fed with 0.1 rotifer ml . These differences were a consequence of ...

Animal grouping behaviors have been widely studied due to their implications for understanding social intelligence, collective cognition, and potential applications in engineering, artificial intelligence, and robotics. An important biological aspect of these studies is discerning which selection pressures favor the evolution of grouping behavior. In the past decade, researchers have begun usin...

seasonal activity and spatial distribution of eoteranychus frosti mcgregor, tydeus longisetosus (elbagouy and momen) and zetzellia mali ewing were studied during 9th july to 22th october 2006 in an unsprayed apple orchard, maragheh region, northwest of iran. also the density dependence interaction between preys and predator was assessed. to estimate the spatial distribution pattern of these spe...

Schizotetranychus nanjingensis Ma & Yuan is a mite pest injurious to the giant bamboo ( Phyllostachys pubscens ) in Fujian, China. The predatory mite Amblyseius longispinosus was explored as a potential biocontrol agent against S. nanjingensis in a series of experiments. Functional response experiments at six different temperatures showed that handling time ( Th ) generally decreased with tempe...

In the study of mechanisms structuring fish communities, mixed competition–predation interactions where large predators feed on prey fish versus those in which small predators compete with prey fish for a shared prey have been the focus of substantial research. We used a long-term data set from a system inhabited by brown trout (Salmo trutta) (predator) and Arctic char (Salvelinus alpinus) (pre...