Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
4542570 | Estuarine, Coastal and Shelf Science | 2006 | 9 Pages |
The population structure, dynamics and distribution of Spisula solida, Diogenes pugilator and Branchiostoma lanceolatum, common species in the south coast of Portugal, were studied in a spatial–temporal manner in order to understand the influence of cross-shore sediment transport and anthropogenic activities. Spisula solida is harvested commercially, whereas D. pugilator and B. lanceolatum are non-target species, with little information available on the population dynamics of these species. The study was performed in 2001–2002, and along a gradient of 100–5000 m from the coastline, corresponding to a depth gradient of between 1 and 32 m deep. Spisula solida was distributed preferentially at 3–12 m deep, and its distribution appeared to be influenced seasonally by the cross-shore sediment dynamics. Results suggested benthic recruitment in June. Some recruitments had no expression (year 2001) since adults were not present, which seems to be a direct impact of clams' fisheries. Diogenes pugilator showed preferential distribution at shallow depths, from 1.3 to 8 m. Results suggested recruitments every 4 months, in June, February and October. Branchiostoma lanceolatum showed the widest distribution, from 7 to 26 m deep. Recruitment seemed to start in June until October, when it attained an abundance peak of juveniles. For both non-target species no clear effects of the cross-shore dynamics or the clams' fisheries impact were visible.