Inter-Research > MEPS > v512 > p9-21  
Marine Ecology Progress Series

via Mailchimp

MEPS 512:9-21 (2014)  -  DOI:

Seasonal variability of δ13C and δ15N of fish and squid in the Cabo Frio upwelling system of the southwestern Atlantic

Lucy S. H. Soares1,*, Elizabeti Y. Muto1, Juliana P. Lopez1, Gabriela R. V. Clauzet1, Iván Valiela2 

1Instituto Oceanográfico da Universidade de São Paulo; Praça do Oceanográfico, 191, São Paulo, SP 05508-120, Brazil
2The Ecosystems Center, Marine Biological Laboratory, Woods Hole, Massachusetts 02543, USA
*Corresponding author:

ABSTRACT: To determine whether shifts occurred in the food web associated with upwelling at the Brazilian western boundary South Atlantic Central Water (SACW), we measured isotopic composition (δ15N and δ13C) of 38 fish and 3 squid species from the Cabo Frio food web. Sampling was performed during the austral summer upwelling period (February 2002) and the austral winter non-upwelling period (July 2001). Mean lipid-corrected δ13 δ13Ccor) values ranged from -20.17 to -15.02‰, and mean δ15N ranged from 10.28 to 16.08‰. An analysis of covariance performed using length as a covariate provided evidence of seasonal effects on the mean fish δ13Ccor and δ15N, with higher values during the non-upwelling period than during the upwelling period. These effects are most likely related to biophysical processes that occurred 1 to 6 mo earlier. The data furnish circumstantial evidence of a link between the dynamics of the SACW and the trophic structure of Cabo Frio. The trophic level of the species of fish and squids ranged between the theoretical trophic levels of 3.6 and 5.1, but there were no discrete steps, rather a continuous gradient in isotopic values. This suggests that these food webs are unstructured and the component species have mixed diets.

KEY WORDS: Food web · Stable isotope · Upwelling system · South-eastern Brazil

Full text in pdf format
Supplementary material 
Cite this article as: Soares LSH, Muto EY, Lopez JP, Clauzet GRV, Valiela I (2014) Seasonal variability of δ13C and δ15N of fish and squid in the Cabo Frio upwelling system of the southwestern Atlantic. Mar Ecol Prog Ser 512:9-21.

Export citation
Mail this link - Contents Mailing Lists - RSS
Facebook - - linkedIn