Meeting Abstract
26.4 Jan. 5 Do morphology and swimming performance predict ecological performance in wild and cultured European sea bass (Dicentrarchus labrax)? HANDELSMAN, C.A.*; NELSON, J.A.; CLAIREAUX, G.; Colorado State University, Fort Collins, CO; Towson University, Towson, MD; Station M�diterran�enne de l�Environnement Littoral, S�te, France Corey.Handelsman@colostate.edu
The ecological performance of animals can be considered a component of Darwinian fitness. Furthermore, in fish, body morphology and swimming performance are often measured in the laboratory but their contribution to individual success in the field is rarely evaluated. Therefore, this critical step in linking performance traits to individual fitness is frequently ignored. We assessed sprint swimming performance and body morphology in wild and cultured juvenile European sea bass (Dicentrarchus labrax) and found substantial variation in both. Moreover, individual sprint swimming performance was found to be repeatable on a daily basis and marginally repeatable following 5-months under simulated natural conditions. These repeatable differences in swimming performance make this test potentially useful as a fitness parameter. To examine one possible source of individual variation in sprint swimming performance and to evaluate our results within the morphology-performance-fitness paradigm, juvenile European sea bass of known performance underwent geometric morphometric analysis of lateral body morphology. Wild fish exhibited a more fusiform body shape and were capable of faster sprint velocities than cultured conspecifics. Replicate groups of wild and cultured fish were released into mesocosms for 14 weeks to simulate natural conditions. Ecological performance in the mesocosms was measured as successful foraging and evading avian predation. Wild fish outperformed cultured fish (35% vs. 0% survival). The significance of morphological variation and sprint performance to the ecological performance of European sea bass populations will be discussed. This project was funded by Funded by the U.S. NSF and CNRS and Ifremer (France).
