IMIS - Marine Research Groups | Compendium Coast and Sea

IMIS - Marine Research Groups

[ report an error in this record ]basket (0): add | show Print this page

Growth and population structure of bloody cockles Senilia senilis at Banc d’Arguin and Bijagós with different environmental conditions and harvesting regimes
El-Hacen, E. M.; Lemrabott, S.Y.C.; Meijer, K.J.; Piersma, T.; Govers, L.L.; van Gils, J.A.; Olff, H. (2023). Growth and population structure of bloody cockles Senilia senilis at Banc d’Arguin and Bijagós with different environmental conditions and harvesting regimes. Mar. Ecol. Prog. Ser. 710: 71-83. https://dx.doi.org/10.3354/meps14291
In: Marine Ecology Progress Series. Inter-Research: Oldendorf/Luhe. ISSN 0171-8630; e-ISSN 1616-1599, more
Peer reviewed article  

Available in  Authors 
    NIOZ: NIOZ Open Repository 395085

Author keywords
    Banc d’Arguin (Mauritania); Bijagós archipelago; Exploitation; Shellfish; Size-selective harvesting

Authors  Top 
  • El-Hacen, E. M.
  • Lemrabott, S.Y.C.
  • Meijer, K.J.
  • Piersma, T., more
  • Govers, L.L., more
  • van Gils, J.A., more
  • Olff, H.

Abstract
    In addition to density-dependent (i.e. food availability) and independent (i.e. abiotic gradients) forces, size-selective harvests of organisms often induce changes to their life history, demography, and reproduction. Shellfish are increasingly overexploited worldwide, and the effect of size-selective harvest on their populations is unclear. The African bloody cockle Senilia senilis is a dominant bivalve in most West African coastal systems, where it is an important source of protein. Here, we studied its population structure (abundance, biomass, and size) and life history traits (age, annual growth rate, and size for age) under contrasting harvesting conditions at the 2 largest intertidal systems in the region: the Bijagós archipelago in Guinea-Bissau (harvested) and Banc d’Arguin in Mauritania (unexploited). To account for local ecological context, we assessed environmental variables that could also affect the abundance and size of S. senilis at these sites. We found that the S. senilis population at Bijagós is significantly denser and older, with lower standing biomass and smaller-sized shells than the population from Banc d’Arguin. In Bijagós, the annual growth is 3-fold lower, and the size-for-age is half of that at Banc d’Arguin. At both sites, S. senilis densities and sizes were correlated with habitat quality indicators: mangrove and mudflat productivity at Bijagós and seagrass and sediment characteristics at Banc d’Arguin. The smaller-sized mature individuals, denser populations, and lower standing biomass at Bijagós compared to Banc d’Arguin are indications of considerable size-selection pressure at Bijagós.

All data in the Integrated Marine Information System (IMIS) is subject to the VLIZ privacy policy Top | Authors