The mere presence of predators often decreases the growth rate of prey individuals, which devote energy and time to predator avoidance mechanisms. However, if time constraints are present, the prey individuals might be forced to neglect predators in order to grow faster. Amphibian larvae lower their activity when exposed to predators, which increases their survival probability but lowers their ...

Predator–prey interactions play an influential role in determining the demographics of a population or species. In the Northwest Atlantic, Atlantic cod, Gadus morhua, once the basis of a lucrative commercial fishery, have not recovered despite regulations imposed on the fishery to reduce harvest rates. One possible reason for the lack of recovery is that high predation pressure on juvenile and ...

survivorship of the immature stage of anopheles culicifacies in damar district were studied through sampling larval and pupal stages from stream bed pools and rice fields during may and august 1993. the duration of each larval instar and the pupal stage was also determined in the laboratory for preparing the survivorship curves and the construction of the life tables. mortality from egg to adul...

Coccinella septempunctata is a nontarget beneficial arthropod and an important aphid predator in agricultural crops. In this study, the toxic effects of neonicotinoid acetamiprid on C. were investigated to determine its applicability efficacy against predator. The results toxicity test showed that second instar larvae most sensitive acetamiprid. LC50 values 1st, 2nd, 3rd, 4th 15.767, 9.412, 18....

Year-class size of marine fish is thought to be determined during the first year life, with density-dependent mortality occuring larval or juvenile stages. However, investigations such dynamics are often limited by data availability. To test this paradigm for winter flounder (Pseudopleuronectes americanus) in Narragansett Bay, Rhode Island, abundances 29 classes moving through seven life stages...

Abstract When exposed to predation risk, some amphibian species show innate responses, while others recognize their predators by learning. To explore the role played each mechanism in assessment of we investigated effects embryonic and larval exposure predator chemical cues on tadpole defensive including behavioural, morphological life history traits. In first experiment, agile frog ( Rana dalm...

Abstract Invasive alien species impacts might be mediated by environmental factors such as climatic warming. For invasive predators, multiple predator interactions could also exacerbate or dampen ecological impacts. These effects may especially pronounced in highly diverse coastal ecosystems that are prone to profound and rapid regime shifts. We examine emergent of warming on the strength intra...

the main objective of the present study was investigation on influences of different brackish water sources on freshwater prawn larval quality and developmental indices. for this study, along a larval period, four brackish water treatments with 12 ppt salinity including diluted marine water, brackish water from marine crystalline salt, brackish water with compounds of new formula and brackish w...

Fishes exhibit a remarkable diversity of body shape as adults; however, it is unknown whether this diversity is reflected in larval stage morphology. Here we investigate the relationship between larval and adult body shape as expressed by body elongation. We surveyed a broad range of ray-finned fish species and compared body shape at larval and adult stages. Analysis shows that the vast majorit...

In this paper, we introduce fractional order of a planar fractional prey-predator system with a nonmonotonic functional response and anti-predator behaviour such that the adult preys can attack vulnerable predators. We analyze the existence and stability of all possible equilibria. Numerical simulations reveal that anti-predator behaviour not only makes the coexistence of the prey and predator ...