Publication Abstract

Understanding the factors that influence European lobster recruitment: A trans-European study of cobble fauna

A. Linnane, B. Ball, J.P. Mercer, G. Van Der Meeren, R.C.A. Bannister, D. Mazzoni, B. Munday, and H. Ringvold

The re-stocking or enhancement of Homarid populations has been the focus of several research projects in recent years. However, despite being able to successfully rear lobsters in captivity, there are few reports of newly settled European lobsters (Hommarus gammarus) in the wild. This is of serious concern for fishery managers when trying to ascertain if restocking or enhancement programmes are successful at the fishery level. Based on published work from the eastern Atlantic seaboard cobble and boulder substrata have been identified as an important nursery habitat for early benthic phase (EBP) American lobsters (Homarus americanus). In Europe, cobble and boulders are utilised by adult lobsters yet little is known of the associated fauna of these substrata, primarily due to the difficulties involved in sampling such sites. This paper, based on an EU-funded research project (LEAR), describes the results of quantitative airlift suction sampling from cobble habitat in Norway, the UK Ireland and Italy. Overall, crustaceans and molluscs were the most abundant species in all countries. While the collective densities of animals per m² of cobble were similar to that of the United States, the species diversity in Europe was significantly higher. Among the crustacea, the reptant decapods dominated at all sites. These findings tend to support the modern day "exclusion hypothesis" that competition and predation from other species limits the successful recruitment of EBP European lobster to the benthos. The results are being used to devise both models and experiments designed with the aim of providing a greater insight into the factors that influence the recruitment of Homarus gammarus.

Reference:

A. Linnane, B. Ball, J.P. Mercer, G. Van Der Meeren, R.C.A. Bannister, D. Mazzoni, B. Munday, and H. Ringvold, 1999. Understanding the factors that influence European lobster recruitment: A trans-European study of cobble fauna. Journal of Shellfish Research 18(2): 719-720.