De Amerikaanse zwaardschede, Ensis directus, en de halfgeknotte strandschelp, Spisula subtruncata, in de Nederlandse kustwateren in 2006
Perdon, K.J.; Goudswaard, P.C. (2006). De Amerikaanse zwaardschede, Ensis directus, en de halfgeknotte strandschelp, Spisula subtruncata, in de Nederlandse kustwateren in 2006. IMARES Wageningen Report, C078/06. Wageningen UR. IMARES: Ijmuiden. 21 pp. Part of: IMARES Wageningen Report. Wageningen UR. IMARES: IJmuiden, more |  |
| Keywords | Water bodies > Coastal waters
Ensis directus (Conrad, 1844) sensu Abbott, 1954 [WoRMS]; Spisula subtruncata (da Costa, 1778) [WoRMS]
ANE, Netherlands [Marine Regions]
Marine/Coastal |
| Abstract | Wageningen IMARES estimated the stock sizes of Ensis directus and Spisula subtruncata in the Dutch coastal waters, as part of the shellfish monitoring programme. The survey was conducted upon request of the Ministry of Agriculture, Nature and Food Quality. IMARES conducted this survey in the summer of 2006, and it was the 12th survey since 1995. In comparison with previous surveys, the survey of 2006 focused more on Ensis directus. The survey estimated stocks in the Dutch coastal waters, with particular attention to the ‘Bird and Habitat Directive Areas’ ‘Waddeneilanden/Noordzeekustzone/Breebaart’ and ‘Voordelta’. A total of more than 37 billion individuals for Ensis directus was found. From this total more than 22 billion individuals were found in the ‘Bird and Habitat Directive Areas’; 17 billion individuals in the ‘Voordelta’ (VHR71) and 6 billion individuals in the protection area ‘Waddeneilanden/Noordzeekustzone/Breebaart’ (VHR 39). Most Ensis directus were found in the ‘Voordelta’, but 75 % of these animals were small. In the coastal zone a total stock of 3.1 million kilogramme fresh-weight was found for Spisula subtruncata. This is lowest stock since the surveys were started in 1995. In 2005 a stock of 3.6 million kilogramme fresh-weight was found. In the ‘Bird and Habitat Directive Areas’ an estimated stock of animals older than one year of 0.5 millions kilogramme fresh-weight was found. The number of juveniles (1-year) was in the same range or slightly above last year, which again reflects a year of poor recruitment. |
| Dataset | - WOT monitoring shellfish stocks : coastal zone, more
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