Range contraction in large pelagic predators

Range contraction in large pelagic predators.

Large reductions in the abundance of exploited land predators have led to significant range contractions for those species. This pattern can be formalized as the range-abundance relationship, a general macroecological pattern that has important implications for the conservation of threatened species. Here we ask whether similar responses may have occurred in highly mobile pelagic predators, spe...

Diet of large pelagic predators of the Western and C

Multiple predators in the pelagic: modelling behavioural cascades

1. The behaviour of predators is rarely considered in models of predator–prey interactions, nor is it common to include multiple predators in models of animal behaviour. 2. We introduce a model of optimal diel vertical migration in zooplankton prey facing predation from two functionally different predators, fish and other zooplankton. Zooplankton predators are themselves subject to predation fr...

Why are there still large pelagic predators in the oceans? Evidence of severe hyper-depletion in longline catch-per-effort

Industrial catch-per-effort (cpue) data are used as an indicator of population abundance and, contrary to strong cautions of potential biases, are often used without regard for spatial interactions as the only data source from which inferences are made. Recent controversy surrounding the status of large predatory pelagic communities has resulted from varying interpretations of the Japanese long...

Predicting Postrelease Survival in Large Pelagic Fish

—Sharks, turtles, billfish, and marine mammals are frequently caught accidentally in commercial fisheries. Although conservationists and fisheries managers encourage the release of these nontarget species, the long-term outcome of released animals is uncertain. Using blue sharks Prionace glauca, we developed a model to predict the long-term survival of released animals based on analysis of smal...