Does Manila clam cultivation affect habitats of the engineer species Lanice conchilega (Pallas, 1766)?

Muséum National d'Histoire Naturelle (MNHN), Département Milieux et Peuplements Aquatiques, CNRS UMR 5178 BOME, CRESCO - Centre de Recherche et d'Enseignement sur les Systèmes Côtiers 38, Rue du Port-Blanc, 35801 Dinard, France.
Marine Pollution Bulletin (Impact Factor: 2.79). 07/2008; 56(8):1429-38. DOI: 10.1016/j.marpolbul.2008.04.046
Source: PubMed

ABSTRACT The major French site of Manila clam Ruditapes philippinarum (Adams and Reeves, 1850) cultivation is located in the Chausey Archipelago where the associated practices are highly mechanized: every steps of production are made with tractor-driven machinery. The Manila clam concessions are concentrated on Lanice conchilega (Pallas, 1766) bioherms, which are known to increase alpha-diversity and to locally modify sediment dynamics. This study focus on the impacts of Manila clam cultivation on (i) the natural populations of L. conchilega and on (ii) the structure of the associated benthic assemblages during the different steps of the farming production cycle. We found that the L. conchilega populations are significantly affected within the concessions where their total abundances drastically decrease, their spatial patterns are modified and the associated benthic assemblages are significantly altered. Our results are discussed in a context of a sustainable management of the Manila clam cultivation in coastal areas.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In several European estuaries, the introduced Manila clam (Ruditapes philippinarum) has become a widespread and predominating species supplanting the native carpet shell clam (Ruditapes decussatus) whereas in other estuaries such as the Bay of Santander (Gulf of Biscay) this pattern has not been detected. Using this estuary as a case study, the potential coexistence/predominance patterns between these two species were explored with the objective of providing insight into the capacity of expansion of R. philippinarum. Firstly, the Ecological Niche Factor Analysis (ENFA) was applied to determine the niches of both species, using seven contemporary environmental variables, i.e. salinity, water depth, current velocity, and sediment sand, gravel, silt and organic matter content. Secondly, ENFA-derived habitat-suitability (HS) maps were simultaneously treated, using geospatial techniques and following HS index-based criteria, to determine the potential distribution patterns. Both species models performed well according to the cross-validation evaluation method. The environmental variables that most determined the presence of both clams were depth, current velocity and salinity. ENFA factors showed that R. philippinarum habitat differs more from the mean environmental conditions over the estuary (i.e. higher marginality) and has less narrow requirements (i.e. lower specialization). R. philippinarum dominated areas, determined by relatively lower current velocities and percentages of sand, higher organic matter contents and slightly shallower depths, were very reduced (i.e. 2.0% of the bay surface) compared to coexistence (47%) and R. decussatus predominance areas (7.4%). These results suggest that HS may regulate the expansion of R. philippinarum. ENFA, together with geospatial analysis of HS index, seems to be a valuable approach to explore the expansion potential of estuarine invasive or introduced species and thus support conservation decisions regarding native species.
    Estuarine Coastal and Shelf Science 01/2015; 152:162-172. DOI:10.1016/j.ecss.2014.11.018 · 2.25 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The aim of the present study was to evaluate the effects of ecosystem engineering caused by reefs of Sabellaria wilsoni (Polychaeta: Sabellariidae) on the meiofauna community of Algodoal Island, in the state of Amazonas, Brazil. Two types of sandy reefs (ball and platform structures) as well as the surrounding sandy sediments of two distinct beaches (low tide terrace and dissipative) were studied. Sampling was carried out at each location in June (rainy season) and December (dry season) 2008, along two profiles perpendicular to the coastal line. A total of 22 taxa of meiofauna were found, with average density of 1,774.2 ind/10 cm(2). Nematoda was the dominant taxon in all seasons and at all locations. ANOVA testing showed that, of the univariate parameters, only richness was significantly different between environments. PERMANOVA highlighted significant differences in the interaction between the environmental factors, as well as between types of reefs and beaches. Changes in structural and abiotic factors led to higher diversity in the reefs, indicating the importance of S. wilsoni as an ecosystem engineer in this Amazonian estuarine sandy beach environment.
    Marine Biodiversity 09/2014; 44(3):403-413. DOI:10.1007/s12526-014-0248-x
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Biogenic reefs composed of the tube-building polychaete L. conchilega are important from a conservation point of view because they noticeably increase the biodiversity in otherwise species poor environments. However, up to now, little or no attention has been paid to the intertidal epi- and hyperbenthic communities associated with the reefs. Therefore, this is the first study which focuses on the effect of L. conchilega reefs on the entire bentho-pelagic community at two different locations. Environmental variables were measured and macro-, epi- and hyperbenthic communities were sampled within a L. conchilega reef and a control area at two locations in France: the bay of the Mont Saint-Michel (BMSM) and Boulogne-sur-Mer (Boulogne). The effect of the reef presence on the benthic community was studied with a 3-factor (Reef, Location and Period) Permanova. In addition, the relationship between the benthic community and the environmental variables were investigated using Distance-based linear models (DistLM). The majority of the collected organisms was sampled in the reef area (macrobenthos: 91 %, epibenthos: 81 % and hyperbenthos: 78.5%) indicating that, independent of the location, the L. conchilega reefs positively affect all three associated benthic communities. However, the extent of the effect seems to be most pronounced for the macrobenthos and less distinct in case of the hyperbenthos. The macro-, and epibenthos are mainly structured by biotic variables (L. conchilega density and macrobenthic food availability respectively), while the hyperbenthos is rather structured by environmental variables. In general, L. conchilega reefs do not only affect abundances and diversity but they substantially steer the structure of the intertidal benthic sandy beach ecosystem.
    Estuarine Coastal and Shelf Science 11/2014; 152:44-55. DOI:10.1016/j.ecss.2014.11.002 · 2.25 Impact Factor

Full-text (2 Sources)

Available from
Jun 1, 2014