Modeled larval fish prey fields and growth rates help predict recruitment success of cod and anchovy in the North Sea

Marine ecology progress series

Johannes Pätsch^3¹  Klaus B. Huebert^1,2²  Marc Hufnagl^1³  Markus Kreus^1,3,4⁴ 

[1] Horn Point Laboratory, University of Maryland Center for Environmental Science, Cambridge, Maryland 21613, USA^2;Institute for Hydrobiology and Fisheries Science, Center for Earth System Research and Sustainability, University of Hamburg, 22767 Hamburg, Germany^1;Institute of Oceanography, Center for Earth System Research and Sustainability, University of Hamburg, 20146 Hamburg, Germany^3;Present address: Federal Waterways Engineering and Research Institute, 22559 Hamburg, Germany^4

关键词: Fish larvae;    Plankton;    Model;    Bottom-up processes;    Prey availability;    Growth;    Recruitment;    Cod;    Anchovy;    North Sea;   

DOI  :  10.3354/meps12615

学科分类：海洋学与技术

来源: Inter-Research

【 摘 要 】

We introduce a new, coupled modeling approach for simulating ecosystem-wide patterns in larval fish foraging and growth. An application of the method reveals how interplay between temperature and plankton dynamics during 1970-2009 impacted a cold-water species (Atlantic cod Gadus morhua) and a warm-water species (European anchovy Engraulis encrasicolus) in the North Sea. Larval fish growth rates were estimated by coupling models depicting trait-based foraging and bioenergetics of individuals, spatiotemporal changes in their prey field, and the biogeochemistry and hydrodynamics of the region. The biomass composition of modeled prey fields varied from 89% nano-, 10% micro-, and 1% mesoplankton to 15% nano-, 20% micro-, and 65% mesoplankton. The mean slope of the normalized biomass size spectrum was near -1.2, consistent with theoretical and empirical estimates. Median larval fish growth rates peaked in June for cod (24% d-1) and in July for anchovy (17% d-1). Insufficient prey resources played a substantial role in limiting the growth rates of cod larvae. Anchovy were consistently limited by cold temperatures. Faster median larval growth during specific months was significantly (p < 0.05) positively associated with detrended (i.e. higher than expected) juvenile recruitment indices in cod (rank correlation Kendall’s tau = 22%) and anchovy (tau = 42%). For cod, the most predictive month was February, which was also when food limitation was most prevalent. The continued development of modeling tools based on first principles can help further a mechanistic understanding of how changes in the environment affect the productivity of living marine resources.

【 授权许可】

Unknown