scholarly journals Underwater television as a fishery-independent method for stock assessment of Norway lobster (Nephrops norvegicus) in the central Adriatic Sea (Italy)

2007 ◽  
Vol 64 (6) ◽  
pp. 1116-1123 ◽  
Author(s):  
Elisabetta B. Morello ◽  
Carlo Froglia ◽  
R. J. A. Atkinson
Keyword(s):  
Adriatic Sea ◽  
Stock Assessment ◽  
Age Determination ◽  
Independent Method ◽  
Nephrops Norvegicus ◽  
Advantages And Disadvantages ◽  
Norway Lobster ◽  
Underwater Television ◽  
Hard Structures ◽  
Muddy Sediments

Abstract Morello, E. B., Froglia, C., and Atkinson, R. J. A. 2007. Underwater television as a fishery-independent method for stock assessment of Norway lobster (Nephrops norvegicus) in the central Adriatic Sea (Italy). – ICES Journal of Marine Science, 64: 1116–1123. Norway lobster is of great commercial importance throughout the NE Atlantic and Mediterranean, where it lives in burrows in muddy sediments. The fact that the species is caught in commercial gear only when it emerges from its burrow and the absence of hard structures available for age determination complicate the application of normal fishery-dependent stock-assessment methodologies. This study provides more evidence of the usefulness of underwater television surveys as a fishery-independent technique to assess the Nephrops stocks of the Adriatic Sea. The results are compared with those of previous studies, and the advantages and disadvantages of using such methodology discussed in an Adriatic context.

Total Arsenic in Raw and Boiled Portions of Norway Lobster (Nephrops norvegicus) from the Central Adriatic Sea

2013 ◽  
Vol 61 (50) ◽  
pp. 12445-12449 ◽  
Author(s):  
Pierina Visciano ◽  
Monia Perugini ◽  
Maurizio Manera ◽  
Maria Cesarina Abete ◽  
Renata Tarasco ◽  
...  
Keyword(s):  
Adriatic Sea ◽  
Total Arsenic ◽  
Nephrops Norvegicus ◽  
Norway Lobster

scholarly journals Investigating the link between Nephrops norvegicus burrow density and sediment composition in Scottish waters

2009 ◽  
Vol 66 (9) ◽  
pp. 2052-2059 ◽  
Author(s):  
Neil Campbell ◽  
Lynda Allan ◽  
Adrian Weetman ◽  
Helen Dobby
Keyword(s):  
Population Size ◽  
Survey Method ◽  
Commercial Fishing ◽  
Sediment Composition ◽  
Nephrops Norvegicus ◽  
Burrow Density ◽  
The North ◽  
Emergence Patterns ◽  
Underwater Television ◽  
Muddy Sediments

Abstract Campbell, N., Allan, L., Weetman, A., and Dobby, H. 2009. Investigating the link between Nephrops norvegicus burrow density and sediment composition in Scottish waters. – ICES Journal of Marine Science, 66: 2052–2059. Nephrops norvegicus is a burrowing decapod, found in the North Atlantic and Mediterranean Sea at depths of 10–1200 m, and currently the most valuable species taken by the commercial fishing industry in Scotland. It constructs and inhabits extensive burrow complexes in suitable muddy sediments. Owing to its variable emergence patterns, catch rates from traditional trawl surveys are not considered a good indicator of population size. Nephrops populations around Scotland are assessed using an underwater television (UWTV) survey method. Sediment samples are collected at the end of each UWTV deployment. This study focuses on two areas off the coast of Scotland and investigates the accuracy of the sediment maps used for assessment purposes, and the relationship between Nephrops burrow density and sediment composition, over the period 2002–2007. Nephrops have a stock-specific relationship with the sediment they inhabit, which retains the same form through fluctuations in population size.

A comparison of methods for stock assessment of the Norway lobster, Nephrops norvegicus, in the Firth of Clyde

1997 ◽  
Vol 32 (1) ◽  
pp. 89-100 ◽  
Author(s):  
I.D. Tuck ◽  
C.J. Chapman ◽  
R.J.A. Atkinson ◽  
N. Bailey ◽  
R.S.M. Smith
Keyword(s):  
Stock Assessment ◽  
Comparison Of Methods ◽  
Nephrops Norvegicus ◽  
Norway Lobster

scholarly journals Ovary resorption in the Norway lobster (Nephrops norvegicus) and its possible causes with special reference to sperm storage

2020 ◽  
Vol 74 (1) ◽  
Author(s):  
Carola Becker ◽  
Jaimie T. A. Dick ◽  
E. Mánus Cunningham ◽  
Mathieu Lundy ◽  
Ewen Bell ◽  
...  
Keyword(s):  
North Sea ◽  
Demographic Data ◽  
Irish Sea ◽  
Natural Phenomenon ◽  
Nephrops Norvegicus ◽  
North East ◽  
The North ◽  
Norway Lobster ◽  
The North Sea ◽  
Reproductive Cycles

Abstract The Norway lobster, Nephrops norvegicus, is an important fisheries species in the North-East Atlantic area. In some circumstances, mature females of Nephrops norvegicus can resorb their ovary rather than completing spawning, but the implications of this phenomenon to reproductive biology and fisheries sustainability are not known. To understand after effects of ovary resorption, we studied long-term demographic data sets (1994–2017) collected from the western Irish Sea and the North Sea. Our considerations focused on potential correlations among the frequency of resorption, female insemination, and body size of resorbing females. Resorption was continuously rare in the western Irish Sea (less than 1%); whereas much higher rates with considerable year-to-year variation were observed in the North Sea (mean 9%). Resorption started in autumn after the spawning season (summer) had passed. The frequency stayed high throughout winter and declined again in spring. As sperm limitation can occur in male-biased fisheries, we expected a lack of insemination could be responsible for resorption, but affected females were indeed inseminated. Resorbing females were significantly larger than other sexually mature females in the North Sea, but the opposite trend was observed in the western Irish Sea. It is therefore possible that other, environmental factors or seasonal shifts, may trigger females to resorb their ovaries instead of spawning. Resorption may as well represent a natural phenomenon allowing flexibility in the periodicity of growth and reproduction. In this sense, observations of annual versus biennial reproductive cycles in different regions may be closely linked to the phenomenon of ovary resorption.

Sign in / Sign up

Export Citation Format

Share Document