FN Archimer Export Format
PT J
TI Trophic relationships between the farmed pearl oyster Pinctada margaritifera and its epibionts revealed by stable isotopes and feeding experiments
BT 
AF LACOSTE, Elise
   RAIMBAULT, Patrick
   HARMELIN-VIVIEN, Mireille
   GAERTNER-MAZOUNI, Nabila
AS 1:1;2:2;3:2;4:1;
FF 1:;2:;3:;4:;
C1 Univ Polynesie Francaise, UMR EIO 241, F-98702 Faaa, Tahiti, France.
   Univ Toulon & Var, Aix Marseille Univ, CNRS INSU IRD, Inst Mediterraneen Oceanol MIO, F-13331 Marseille, France.
C2 UNIV POLYNESIE FRANCAISE, FRANCE
   UNIV TOULON, FRANCE
UM EIO
IF 2.905
TC 10
UR https://archimer.ifremer.fr/doc/00664/77582/79564.pdf
LA English
DT Article
DE ;Ascidian;Biofouling;Trophic interactions;Stable isotope;Flow cytometry
AB Bivalve cultures support a host of epibionts, mainly suspension feeders, which can compete for food resources with the cultivated bivalves. However, the magnitude of interspecific competition for food in bivalve aquaculture settings remains inconclusive, especially in tropical areas. We investigated the interactions for food between the farmed pearl oyster Pinctada margaritifera and its epibionts, using stable isotope analysis and feeding experiments. Inter-and intraspecific variations of delta C-13 and delta N-15 stable isotope ratios (SIRs) were determined for oysters in the presence or absence of epibionts. The diet of the most abundant epibionts, Herdmania momus and Didemnum sp., was specified using isotope measurements and flow cytometry during feeding experiments, to determine the main phytoplankton groups consumed by these ascidians in natural conditions. The absence of intraspecific variation in SIRs among oysters with or without epibionts suggested that the diet of P. margaritifera was not affected by the presence of epibionts, indicating a reduced diet overlap and no food limitation. The delta C-13 signature of ascidians (-21 parts per thousand) was lower than that of oysters (-18 parts per thousand), indicating a difference in organic matter sources ingested by these filter feeders despite receiving the same food mixture. While the main carbon source of oysters came from large particulate organic matter (POM) > 20 mu m, our results showed that the diet of ascidians mainly came from smaller particles (POM < 20 mu m) and reflects the composition of ambient water (mainly picophytoplankton < 2 mu m), which confirmed their lack of food selectivity. In the studied conditions, food competition between oysters and epibionts, specifically ascidians, was not a limiting factor, in spite of a diet overlap for nanophytoplankton. 
PY 2016
SO Aquaculture Environment Interactions
SN 1869-215X
PU Inter-research
VL 8
UT 000377605600005
BP 55
EP 66
DI 10.3354/aei00157
ID 77582
ER

EF