Isotope trophic-step fractionation of suspension-feeding species: Implications for food partitioning in coastal ecosystems

Determination of diet in Manila clams by spatial analysis of stable isotopes

“…To our knowledge, tissue-specific δ 13 C trophic enrichment has never been estimated for marine bivalves, despite recent experimental studies by Yokoyama et al (2005a), Paulet et al (2006) and Dubois et al (2007). Our experimental results are in accordance with Paulet et al (2006) and field studies which analyzed tissue-specific trophodynamics in bivalves (Stephenson & Lyon 1982, Lorrain et al 2002, Malet et al 2007).…”

Tracing sewage and natural freshwater input in a Northwest Mediterranean bay: Evidence obtained from isotopic ratios in marine organisms

“…In addition, the digestive glands of Pecten maximus and Crassostrea gigas have been found to have the highest carbon incorporation index, suggesting that this organ is the most appropriate to detect short-term food source variations (Paulet et al, 2006). When using entire organisms of Mytilus edulis, Dubois et al (2007) found a half-life of 8.9 days for the δ 13 C and 14.1 days for the δ 15 N. In our study, these values would represent an 81%, 96% and 94% replacement of tissue carbon and 64%, 87% and 82% replacement of tissue nitrogen during the months of April, August and November, respectively. As the turnover rate of the digestive gland is higher than for the whole animal, we can assume that isotopic equilibrium (i.e., the isotopic composition of mussel tissues is completely determined by the isotopic composition of the new diet) is approximately reached during our caging experiments.…”

“…Owing to their large filtering capacity, they accumulate matter suspended in the water column and provide a long-term integrated signal of their food sources (Dubois et al, 2007;Gillikin et al, 2006;Machas and Santos, 1999); therefore, the use of bivalves is common in environmental studies. However, fractionation processes, such as the preferential use of one isotope over another during biochemical processes, and the turnover rate of tissue cells must be taken into account when using isotopic analysis to assess the dietary signature of these organisms (Deudero et al, 2009;Dubois et al, 2007).…”

Trophic connectivity between offshore upwelling and the inshore food web of Banc d'Arguin (Mauritania): New insights from isotopic analysis

“…16 feeding bivalves, which represented most of our samples in the subtidal BA, is likely integrated over at least 3 months according to recent controlled feeding experiments (Paulet et al, 2006;Dubois et al, 2007) and field studies (Raikow and Hamilton, 2001;Carlier et al, 2007).…”

“…The model was run for 500,000 iterations, discarding the first 50,000 iterations. Trophic enrichment values were adapted from literature values obtained with marine bivalves (Dubois et al, 2007;Yokoyama et al, 2005Yokoyama et al, , 2008 and herbivorous marine invertebrates (Vander Zanden and Rasmussen 2001): 3.7 ± 0.9‰ and 0.7 ± 1.2‰ for N and C, respectively. The model was run only with two sources, suspended POM originating from upwelling and suspended POM from inshore waters, as other potential food sources, such as suspended epiphytic algae, macroalgae, and drifting fragments of mangroves and seagrass, are not abundant at the subtidal part of BA (Wolff and Smit, 1990;Hemminga and Nieuwenhuize, 1991;Wolff et al, 1993b).…”