Searching for the true diet of marine predators: incorporating Bayesian priors into stable isotope mixing models
Reconstructing the diet of top marine predators is of great significance in several key areas of applied ecology, requiring accurate estimation of their true diet. However, from conventional stomach content analysis to recent stable isotope and DNA analyses, no one method is bias or error free. Here, we evaluated the accuracy of recent methods to estimate the actual proportion of a controlled diet fed to a top-predator seabird, the Little penguin (Eudyptula minor). We combined published DNA data of penguins scats with blood plasma δ15N and δ13C values to reconstruct the diet of individual penguins fed experimentally. Mismatch between controlled (true) ingested diet and dietary estimates obtained through the separately use of stable isotope and DNA data suggested some degree of differences in prey assimilation (stable isotope) and digestion rates (DNA analysis). In contrast, combined posterior isotope mixing model with DNA Bayesian priors provided the closest match to the true diet. We provided the first evidence suggesting that the combined use of these complementary techniques may provide better estimates of the actual diet of top marine predators- a powerful tool in applied ecology in the search for the true consumed diet.
History
Publication title
PLoS ONEVolume
9Article number
e92665Number
e92665Pagination
1-5ISSN
1932-6203Department/School
Institute for Marine and Antarctic StudiesPublisher
Public Library of SciencePlace of publication
United StatesRights statement
Copyright 2014 Chiaradia et al. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International (CC BY 4.0) License, (https://creativecommons.org/licenses/by/4.0/) which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Repository Status
- Open