Predicting coexistence and predominance patterns between the introduced Manila clam (Ruditapes philippinarum) and the European native clam (Ruditapes decussatus)
Bidegain, G.; Bárcena, J.F.; García, A.; Juanes, J.A. (2015). Predicting coexistence and predominance patterns between the introduced Manila clam (Ruditapes philippinarum) and the European native clam (Ruditapes decussatus). Est., Coast. and Shelf Sci. 152: 162-172. https://dx.doi.org/10.1016/j.ecss.2014.11.018
In: Estuarine, Coastal and Shelf Science. Academic Press: London; New York. ISSN 0272-7714; e-ISSN 1096-0015, more
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| Keywords |
Products > Food > Foods > Products > Seafoods > Bivalvia > Shellfish > Clams
Water bodies > Coastal waters > Coastal landforms > Coastal inlets > Estuaries
Marine/Coastal |
| Authors | | Top |
- Bidegain, G.
- Bárcena, J.F.
- García, A.
- Juanes, J.A.
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| 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 betweenthese 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 indexbased 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 thatR. 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 introducedspecies and thus support conservation decisions regarding native species. |
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