Sexual segregation in the foraging behaviour of a slightly dimorphic seabird: Influence of the environment and fishery activity

作者：José Manuel Reyes‐González, Fernanda De Felipe, Virginia Morera‐Pujol, Andrea Soriano‐Redondo, Leia Navarro‐Herrero, Laura Zango, Salvador García‐Barcelona, Raül Ramos, Jacob González‐Solís · 发表于：Journal of Animal Ecology · 年份：2021 · DOI：10.1111/1365-2656.13437 · 被引用次数：32 · 研究领域：Avian ecology and behavior、Animal Ecology and Behavior Studies、Wildlife Ecology and Conservation

Sexual segregation in foraging strategies has been little studied in marine species with slight sexual size dimorphism (SSD), particularly regarding the role of environmental conditions and fishery activities. Sexual differences in fishery attendance are of particular concern because uneven mortality associated with bycatch may exacerbate impacts in wildlife populations. Using a seabird species with slight SSD, the Scopoli's shearwater Calonectris diomedea, we assessed sexual differences in foraging strategies and evaluated whether annual environmental conditions and fishery activity shaped such differences. We used a 4-year dataset combining bird GPS tracking, stable isotope analysis, the North Atlantic Oscillation index (NAO, as main proxy of the annual environmental conditions), and fishing vessel positioning data (Vessel Monitoring System, VMS) from the North Western Mediterranean, a region under intense fishery pressure. From 2012 to 2015, we tracked 635 foraging trips from 78 individuals. Females showed a greater foraging effort, a lower fishery attendance, a lower trophic level, and a narrower isotopic niche width than males. Moreover, in years with unfavourable environmental conditions, both sexes showed a lower fishery attendance and increased foraging effort compared to the year with most favourable conditions. Our results revealed that environmental conditions influence space use, feeding resources and fishery attendance differently in males and females, overall su...