eCite Digital Repository

Stable isotope and signature fatty acid analyses suggest reef manta rays feed on demersal zooplankton

Citation

Couturier, LIE and Rohner, CA and Richardson, AJ and Marshall, AD and Jaine, FRA and Bennett, MB and Townsend, KA and Weeks, SJ and Nichols, PD, Stable isotope and signature fatty acid analyses suggest reef manta rays feed on demersal zooplankton, PLoS ONE, 8, (10) Article e77152. ISSN 1932-6203 (2013) [Refereed Article]


Preview
PDF
975Kb
  

Copyright Statement

Copyright 2013 Couturier et al. Licensed under Creative Commons Attribution 4.0 International (CC BY 4.0) https://creativecommons.org/licenses/by/4.0/

DOI: doi:10.1371/journal.pone.0077152

Abstract

Assessing the trophic role and interaction of an animal is key to understanding its general ecology and dynamics. Conventional techniques used to elucidate diet, such as stomach content analysis, are not suitable for large threatened marine species. Non-lethal sampling combined with biochemical methods provides a practical alternative for investigating the feeding ecology of these species. Stable isotope and signature fatty acid analyses of muscle tissue were used for the first time to examine assimilated diet of the reef manta ray Manta alfredi, and were compared with different zooplankton functional groups (i.e. near-surface zooplankton collected during manta ray feeding events and non-feeding periods, epipelagic zooplankton, demersal zooplankton and several different zooplankton taxa). Stable isotope δ15N values confirmed that the reef manta ray is a secondary consumer. This species had relatively high levels of docosahexaenoic acid (DHA) indicating a flagellate-based food source in the diet, which likely reflects feeding on DHA-rich near-surface and epipelagic zooplankton. However, high levels of ω6 polyunsaturated fatty acids and slightly enriched δ13C values in reef manta ray tissue suggest that they do not feed solely on pelagic zooplankton, but rather obtain part of their diet from another origin. The closest match was with demersal zooplankton, suggesting it is an important component of the reef manta ray diet. The ability to feed on demersal zooplankton is likely linked to the horizontal and vertical movement patterns of this giant planktivore. These new insights into the habitat use and feeding ecology of the reef manta ray will assist in the effective evaluation of its conservation needs.

Item Details

Item Type:Refereed Article
Keywords:carbon 13, fatty acid, functional group, lipid, omega 6 fatty acid, stable isotope, carbon, nitrogen, omega 6 fatty acid
Research Division:Biological Sciences
Research Group:Ecology
Research Field:Marine and Estuarine Ecology (incl. Marine Ichthyology)
Objective Division:Environment
Objective Group:Flora, Fauna and Biodiversity
Objective Field:Marine Flora, Fauna and Biodiversity
UTAS Author:Nichols, PD (Dr Peter Nichols)
ID Code:118939
Year Published:2013
Web of Science® Times Cited:49
Deposited By:Zoology
Deposited On:2017-07-24
Last Modified:2017-10-16
Downloads:81 View Download Statistics

Repository Staff Only: item control page