Effects of preferred prey density and temperature on feeding success and recent growth in larval mackerel of the southern Gulf of St. Lawrence

Marine Ecology Progress Series

Louis Fortier¹  Martin Castonguay¹  Dominique Robert¹ 

关键词: Fish larvae;    Prey availability;    Temperature;    Feeding success;    Recent growth;    Otolith microstructure;    Atlantic mackerel;    Scomber scombrus;   

DOI  :  10.3354/meps07833

学科分类：海洋学与技术

来源: Inter-Research

【 摘 要 】

ABSTRACT: We evaluated the effects of preferred prey density and temperature on the feeding success and recent growth of Atlantic mackerel larvae from 4 consecutive annual cohorts (1997 to 2000) in the southern Gulf of St. Lawrence. Individual feeding success (residuals of the linear regression of preferred prey carbon in the gut content on larval length) and recent growth (average width of last 3 otolith increments) were determined for a stratified subsample of larvae in each year and among different length classes. The density of preferred prey best explained variations in feeding success and growth in first-feeding larvae (<7 mm), while temperature was the main source of growth variability during older larval stages. The feeding success and growth of early larvae increased with the density of Pseudocalanus sp. nauplii until a similar satiation threshold of 1 µgC l^–1. Recent growth increased linearly with temperature during the late larval stage, without any indication of a temperature optimum. These results suggest that high abundance of the preferred prey at the onset of exogenous feeding and relatively warm temperature during the larval growth season are important prerequisites for the emergence of a strong year class in Atlantic mackerel.

【 授权许可】

Unknown