Isotopic shifts with size, culture habitat, and enrichment between the diet and tissues of the Japanese scallop Mizuhopecten yessoensis (Jay, 1857)

• Published in: Marine biology 2010-10, Vol.157 (10), p.2157-2167
• Main Authors: Aya, Frolan A., Kudo, Isao
• Format: Article
• Language: English
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Biological and medical sciences; Biological research; Biology, Experimental; Biomedical and Life Sciences; Diet; Digestive glands; Dimensional analysis; Enrichment; Food and nutrition; Freshwater & Marine Ecology; Fundamental and applied biological sciences. Psychology; Habitat (Ecology); Habitats; Ingestion; Invertebrates; Isotopes; Isotopic enrichment; Life Sciences; Marine; Marine & Freshwater Sciences; Marine biology; Microbiology; Mizuhopecten yessoensis; Mollusca; Mollusks; Ocean bottom; Ocean floor; Oceanography; Original Paper; Particulate organic matter; Physiological aspects; Salinity; Scallops; Sea water ecosystems; Shellfish; Signatures; Stable isotopes; Studies; Synecology; Tissues; Zoology
• ISSN: 0025-3162; 1432-1793
• DOI: 10.1007/s00227-010-1480-y

Use of stable isotope signatures to trace diet patterns in cultured marine bivalves, particularly when changing culture habitat, requires knowledge of the isotopic shift and enrichment between diet and consumer’s tissues. The aim of this study was to determine the patterns of isotope change and the variability of enrichment values (∆δ 13 C and ∆δ 15 N) in different tissues (muscle, gonad, digestive gland) of the Japanese scallop ( Mizuhopecten yessoensis ). It was hypothesized that the isotopic signatures of a consumer’s tissues changed during settlement and that the changes were related to variations in the isotopic signatures of food sources and gut contents. Particular attention was paid to the isotope enrichment between the diet and a consumer’s tissues using isotope analysis of gut content. Muscle δ 15 N values decreased significantly 3–5 months post-settlement in a nearshore seabed, concomitant with the ingestion of lower δ 15 N food. For juvenile scallops, sinking particles (SP) were considered a more important dietary source than suspended particulate organic matter (SPOM), based on the correspondence between SP and gut contents δ 13 C. Enrichment values (∆δ 13 C and ∆δ 15 N) varied with tissue and season. ∆δ 15 N was 2.4‰ in muscle, 1.2‰ in gonad, and 0.7‰ in the digestive gland. ∆δ 13 C was 3.2‰ in muscle, 2.3‰ in gonad, and −0.5‰ in the digestive gland. ∆δ 15 N was the lowest in summer (0.3‰), and ∆δ 13 C was the highest in autumn (2.8‰). ∆δ 15 N values were significantly influenced by age, but not ∆δ 13 C. Patterns of isotope ratios and enrichment values may be related to physiological attributes and differences in diet. This is the first study to demonstrate isotopic shift and enrichment encountered in different tissues of a cultured scallop when changing culture habitat.