捕捞饵料鱼何时会对其掠食者产生影响

该论文作者为:华盛顿大学的Ray Hilborn博士、Ricardo O. Amoroso博士和Eugenia Bogazzi博士;罗格斯大学的Olaf P. Jensen博士;阿根廷国家科学与技术研究委员会(CONICET)海洋系统研究中心的Ana M. Parma博士;加州大学圣塔芭芭拉分校的Cody Szuwalski博士;不列颠哥伦比亚大学的Carl J. Walters博士。

Abstract

This paper explores the impact of fishing low trophic level “forage” species on higher trophic level marine predators including other fish, birds and marine mammals. We show that existing analyses using trophic models have generally ignored a number of important factors including (1) the high level of natural variability of forage fish, (2) the weak relationship between forage fish spawning stock size and recruitment and the role of environmental productivity regimes, (3) the size distribution of forage fish, their predators and subsequent size selective predation (4) the changes in spatial distribution of the forage fish as it influences the reproductive success of predators. We show that taking account of these factors generally tends to make the impact of fishing forage fish on their predators less than estimated from trophic models. We also explore the empirical relationship between forage fish abundance and predator abundance for a range of U.S. fisheries and show that there is little evidence for a strong connection between forage fish abundance and the rate of change in the abundance of their predators. We suggest that any evaluation of harvest policies for forage fish needs to include these issues, and that models tailored for individual species and ecosystems are needed to guide fisheries management policy.

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VIDEO: Leading Fisheries Scientists Challenge Lenfest Research that Recommended Cutting Catch of Forage Fish