open access

https://hdl.handle.net/2115/68401

Nitrogen stable isotopes reveal age-dependent dietary shift in the Japanese scallop Mizuhopecten yessoensis

英語

zooplankton

2017-03

Taylor & Francis

Isotopes in environmental and health studies

53(1)

80-90

Ontogenetic niche shifts in diet are a consequence of changes in body size or resource partitioning between age classes. To better resolve the feeding patterns of the Japanese scallop Mizuhopecten yessoensis, we examined the relative importance of age and size in the diet of this species using stable isotope ratios of carbon (C-13) and nitrogen (N-15) from 2006 to 2009. Contribution of food sources was quantified using an isotope mixing model by comparing the muscle tissue isotope ratios to those of suspended particulate organic matter (SPOM) and their zooplankton prey (e.g. micro- and meso-zooplankton). Unlike the C-13 values, which remained constant with age and size, muscle N-15 values were more positively correlated with age accounting for 69% of variations than size with only 46%. Increasing N-15 values with age suggested that shifts in diet from SPOM to micro- and meso-zooplankton occurred during ontogeny in M. yessoensis. Results of the isotope mixing model indicated that SPOM contribution to scallop's diet decreased from 68 to 8% while those of zooplankton increased from 15 to 50% with increasing age. This study concludes that age-related dietary shift explains the enrichment of N-15, as a result of predation on zooplankton by M. yessoensis.

学術雑誌論文

Accepted Manuscript

This is an Accepted Manuscript of an article published by Taylor & Francis in Isotopes in Environmental and Health Studies on March 2017, available online: http://www.tandfonline.com/10.1080/10256016.2016.1186024.

1025-6016

AA11072326