Caring about the future

LobAssess – Norway lobster stocks in Portugal: Assessment using information on larval production and ecology
Coordinator - Henrique Queiroga
Programme - POCTI
Execution dates - 2005-10-01 - 2008-09-29 (36 Months)
Funding Entity - FCT
Funding for CESAM - 35080 €
Total Funding - 89500 €
Proponent Institution - IPIMAR
Participating Institutions
Universidade de Aveiro
Universidade do Algarve

Project Description

The Norway lobster, Nephrops norvegicus, is one of the most valuable Portuguese shellfish resources. According to the report of the ICES Nephrops Working Group, Portuguese stocks need urgent management measures. However, assessment methods currently applied to Portuguese stocks are unsuitable for this benthic species with a strong and persistent spatial structure. Moreover, local populations are open to interchange of individuals through larval dispersal, which may enhance stability of the stocks. These aspects have never been taken in account in assessment and management plans. The LobAssess project will develop and independent estimate of the biomass of one of the Portuguese stocks of the species (Functional Unit (FU) 28, southwest coast, Figure 1), based on the Annual Larval Production method. This method does not have the shortcomings of available assessment tools, such as Virtual Population Analysis or Length Cohort Analysis, which have been developed for traditional finfish stocks. The assessment made will be contrasted with the values produced by current assessment plans. LobAssess will also estimate rates of larval flow over the FU 28 area and the interchange of larvae with neighbouring areas, by the development of a numerical model that integrates information on circulation components and larval behaviour. Conclusions on the origin of larvae recruiting to FU 28 will be backed up by genetic analysis using primers specifically developed for the species. The specific objectives of LobAssess are organised into 8 tasks (see Figure 2): 1. Larval production and mortality 2. Population biology 3. Stock assessment 4. Genetics 5. Dispersal modelling 6. Larval dispersal and vertical migration 7. Management measures 8. Scientific co-ordination and workshop organization The LobAssess research team includes members from the Instituto de Investigação das Pescas e do Mar (IPIMAR), of the Universidade de Aveiro and of the Universidade do Algarve. The IPIMAR has expertise in larval ecology and taxonomy, in addition to assessment. Researchers of the Universidade de Aveiro have been working for several years on bio-physical interactions controlling dispersal and recruitment of decapod crustaceans, including numerical modelling. Members of the Universidade do Algarve have skills on population biology, genetics and management of Nephrops. LobAssess has a strong component of post-graduated training, and will use national platforms for work at sea. The LobAssess project will improve our knowledge on larval ecology of deep-sea resources, a subject that has been overlooked by fisheries biologists. It will use an appropriate assessment method and suggest management measures accounting for connectance of local populations. Hopefully, the LobAssess project will produce a more accurate assessment of the situation of Portuguese stocks, on which to base realistic and socially acceptable management measures.

Project webpage

CESAM members on this project

CESAM Funding: UIDP/50017/2020 + UIDB/50017/2020 + LA/P/0094/2020