Stable isotope signatures reveal small-scale spatial separation in populations of European sea bass

Cambie, G. and Kaiser, M.J. and Marriott, A.L. and Fox, J. and Lambert, G. and Hidding, J.G. and Overy, T. and Bennet, S.A. and Leng, M.J. and McCarthy, I.D. (2016) Stable isotope signatures reveal small-scale spatial separation in populations of European sea bass. Marine Ecology Progress Series, 546. pp. 213-223. DOI: 10.3354/meps11636

36468.pdf - Accepted Version

Download (721kB) | Preview


Scientific information about European sea bass (Dicentrarchus labrax) stocks in NE Atlantic is limited and a more accurate definition of the stock boundaries in the area is required to improve assessment and management advice. Here we study the connectivity and movement patterns of European sea bass in Wales (UK) using the stable isotope (δ13C and δ15N) composition of their scales. Analysis of fish scale δ13C and δ15N values in the last growing season was performed on 189 adult sea bass caught at nine coastal feeding grounds. Fish >50 cm total length (TL) caught in estuaries had very low δ13C and this is characteristic of fresh water (organic/soil) input, indicating the primary use of estuaries as feeding areas. A random forest classification model was used to test if there was a difference in δ15N and δ13C values between north, mid and south Wales and whether it was possible to correctly assign the fish to the area where it was caught. This analysis was restricted to fish of a similar size range (40-50 cm TL) caught in open coastal areas (n=156). The random forest classification model showed that about 75% of the fish could be correctly assigned to their collection region based on their isotope composition. The majority of the misclassifications of fish were fish from north Wales classifying to mid Wales and vice versa, while the majority of fish from south Wales were correctly assigned (80%). Our findings suggest that two sub-populations of sea bass in Welsh waters use separate feeding grounds (south vs. mid/north Wales), and may need separate management.

Item Type: Article
Subjects: Research Publications
Departments: College of Natural Sciences > School of Ocean Sciences
Date Deposited: 14 Apr 2016 02:33
Last Modified: 21 Mar 2017 03:20
ISSN: 0171-8630
URI: http://e.bangor.ac.uk/id/eprint/6497
Identification Number: DOI: 10.3354/meps11636
Publisher: Inter Research
Administer Item Administer Item

eBangor is powered by EPrints 3 which is developed by the School of Electronics and Computer Science at the University of Southampton. More information and software credits.