Size, diet, and condition of age-0 Pacific cod (Gadus macrocephalus) during warm and cool climate states in the eastern Bering sea

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• 作者：Edward V. Farley Jr.^a ; ^{ed.farley@noaa.gov} ; Ron A. Heintz^a ; ^{ron.heintz@noaa.gov} ; Alex G. Andrews^a ; ^{alex.andrews@noaa.gov} ; Thomas P. Hurst^b ; ^{thomas.hurst@noaa.gov}
• 关键词：Bering Sea ; Pacific cod ; Age-0 ; Energetics ; Diet ; Winter survival
• 刊名：Deep Sea Research Part II: Topical Studies in Oceanography
• 出版年：2016
• 出版时间：December 2016
• 年：2016
• 卷：134
• 期：Complete
• 页码：247-254
• 全文大小：695 K
• 卷排序：134

文摘

The revised Oscillating Control Hypothesis for the Bering Sea suggests that recruitment of groundfish is linked to climatic processes affecting seasonal sea ice that, in turn, drives the quality and quantity of prey available to young fish for growth and energy storage during their critical life history stages. We test this notion for age-0 (juvenile) Pacific cod (Gadus macrocephalus) by examining the variability in size, diet, and energetic condition during warm (2003–2005), average (2006), and cool (2007–2011) climate states in the eastern Bering Sea. Juvenile cod stomachs contained high proportions of age-0 walleye pollock (by wet weight) during years with warm sea temperatures with a shift to euphausiids and large copepods during years with cool sea temperatures. Juvenile cod were largest during years with warm sea temperatures and smallest during years with cool sea temperatures. However, energetic status (condition) of juvenile cod was highest during years with cool sea temperatures. This result is likely linked to the shift to high quality, lipid-rich prey found in greater abundance on the shelf and in the stomach contents of juvenile cod during cool years. Our examination of juvenile cod size, diet, and energetic status provided results that are similar to those from studies on juvenile pollock, suggesting that the common mechanisms regulating gadid recruitment on the eastern Bering Sea shelf are climate state, prey quality and quantity, and caloric density of gadids prior to winter.