Geostatistical exploration of integrated VMS data from the Aran Ground Nephrops fishery with associated survey estimates: Establishing the relationship between fishing, biotic and abiotic variables
Vogel, C. (2010). Geostatistical exploration of integrated VMS data from the Aran Ground Nephrops fishery with associated survey estimates: Establishing the relationship between fishing, biotic and abiotic variables. MSc Thesis. Erasmus Mundus Master of Science in Marine Biodiversity and Conservation (EMBC)/Universidade do Algarve: Faro. 28 + Appendices pp. |
Available in | Author | | Document type: Dissertation
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Keywords | Nephrops norvegicus (Linnaeus, 1758) [WoRMS] Marine/Coastal |
Abstract | This study is a self-standing work on the fishery of Nephrops norvegicus on the Aran Grounds, off the West coast of Ireland. This fishery is of special interest due to the high economic value of the species worldwide and its primary importance in the local economy. The aim is to draw the relationship between data from different sources, both commercial and scientific, which give us information on the biological occurrence and characteristics of the species burrow density estimates from UWTV, population data and its availability to commercial trawling effort and LPUE in relation to environmental parameters sediment %Silt-Clay content. To do so, we used two main tools: geostatistics applied to GIS and Generalized Additive Models in SAS . Results obtained corroborate previous findings. Nephrops favour sediment of high %Silt-Clay to establish their burrows, and there is a non-linear relationship between the size of the animals and burrow density. The link between burrow density and LPUE is less evident and can only be partially explained from the data available to this study. Results suggest a one-year lag in the relationship, which needs to be further explored by integrating larvae recruitment and additional abiotic parameters in the analysis. The pursuit of this work with additional survey data in the future can be of great interest to understand further the relationship between biotic factors and fisheries landings of Nephrops norvegicus in a stock management perspective. |
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