Feeding response of the polychaete Sabellaria alveolata (Sabellariidae) to changes in seston concentration

Abstract

Sabellaria alveolata is a tube-building gregarious polychaete that constructs large biogenic reefs. In macrotidal shellfish ecosystems, this species competes for food with cultivated suspension-feeders. The suspension-feeding activity and clearance rate of S. alveolata were investigated in response to changes in seston concentration. A flow-through system was designed to study 225 cm 2 reef blocks with more than 500 individuals. The experimental conditions were characterized by increasing concentrations of suspended particulate matter ranging from 6.5 to 153.8 mg L −1 , while the organic content of the diet (microalgae Skeletonema costatum) decreased inversely from 49 to 9%, to mimic the dilution of organic matter by inorganic particles, characteristic of tidal resuspension. We showed that the clearance rate exponentially decreased in relation to an increase in SPM concentration. Clearance rate was estimated at 5.3 10 − 3 L h − 1 or 0.93 L h − 1 g − 1 (dry weight) for the lowest seston concentration (SPM = 6.5 mg L − 1) and reached the asymptote at CR = 1.97 10 − 3 L h − 1 or 0.35 L h − 1 g − 1 (dry weight) when SPM exceeded 45 mg L − 1. Using picture analyses of polychaete movements, we showed that, paradoxically, an increase in SPM concentration did not adversely affect the feeding activity of S. alveolata since the number of filtering individuals remained stable from SPM = 6.5 to 55.5 mg L − 1. These values were applied at the scale of the bay of Mont-Saint-Michel (France) to demonstrate that the filtration pressure of large populations of wild suspension-feeders should not be underestimated when the carrying capacity has to be assessed in the context of increasing bivalve cultures.

The conservation status of Sabellaria alveolata (L.) (Polychaeta: Sabellariidae) reefs in the Bay of Mont‐Saint‐Michel

“…A few years after the change in shellfish structure, as modelled, a decrease of mean grain‐size was observed, higher in the fore‐reef area. The new scheme has resulted in several problems; first, an increase of suspended particulate matter (organic and inorganic) has affected the filtration rate of S. alveolata (Dubois et al , ) by abrading feeding organs and clogging up the tubes. Second, the decrease of current velocity has increased the sedimentation and decreased sand grain re‐suspension leading to a decrease in tube‐building activity, since the tubes are built by the polychaetes by catching sand particles drifting near their tube aperture.…”

Looking at the soft-bottom around a coastal coral reef: the impact of terrigenous input on Polychaeta (Annelida) community

“…This same study was used to classify species according to the feeding habit of their families, but other studies were used to revise them (JONES, 1968;NOYES, 1980;WORD, 1980;PLEIJEL, 1983;DOBBS;SCHOLLY, 1986;FONG, 1987;GASTON, 1987;CARRASCO;OYARZÚN, 1988;NIELSEN et al, 1995;FERNER;JUMARS, 1999;GIANGRANDE et al, 2000;BRITAEV;LYSKIN, 2002;LEE et al, 2004;COSTA et al, 2006;AMARAL, 2006;DUBOIS et al, 2009;SMART;DASSOW, 2009;PLYUSCHEVA et al, 2010). Generalized linear models with distance, sediment (Sed) and/or transect (Tr) as predictor variables were also fitted to evaluate the functional community (trophic groups).…”

Role of Reef-Building, Ecosystem Engineering Polychaetes in Shallow Water Ecosystems

“…Sabellaria alveolata (Sabellidae) Intertidal and subtidal (0-10 m) Filter-feeding activity Control of primary production [39,40] Mont-Saint-Michel (France)…”

“…The serpulid Serpula vermicularis usually occurs as a solitary species but forms massive reefs at three sites in north-west Europe (Ardbear Lough and Killary Harbour in Ireland, Loch Creran in Scotland; Figure 1D), which can be up to 50 cm height and 60 cm width [39,75]. The area occupied by reef has been estimated at 108 ha and the coverage ranged from 3% to 25% in Loch Creran [75].…”