Marine & Environmental Sciences Faculty Articles
Dietary Niche Overlap in a Nearshore Elasmobranch Mesopredator Community
Document Type
Article
Publication Title
Marine Ecology Progress Series
ISSN
0171-8630
Publication Date
3-14-2011
Keywords
Stable isotope, Resource partitioning, Individual specialization, Stingray, Batoid, Elasmobranch, Shark
Abstract
Understanding mesopredator trophic interactions is crucial to understanding the dynamics of food webs because mesopredators provide the link between apex predators and lower trophic levels. Using stable isotopic analysis and stomach content analysis, we examined dietary niche overlap within a diverse elasmobranch mesopredator community in Shark Bay, Western Australia. Isotopic values (δ13C and δ15N) were consistent with most species being highly dependent on a seagrass-based food web. Differences were observed between the mean isotopic values of species, but there was a great deal of overlap in the isotopic niche space used by the community when examined at the level of individuals. Stomach contents also suggest dietary overlap among the diets of Himantura spp. and Glaucostegus typus, which contained many of the same prey species, primarily crustaceans typically associated with seagrass habitats, although in different proportions. Diet data also suggest that, despite having isotopic values similar to other species, Pastinachus atrus appears to feed on sandflat-associated species. In this community, variation within the groups examined, possibly due to individual specialization, appears to result in high resource overlap and may be a key component allowing for high diversity in this system and is perhaps crucial to understanding the role of mesopredators in community trophic dynamics.
DOI
10.3354/meps08988
Volume
425
First Page
247
Last Page
260
Additional Comments
NSF grant #s: OCE0526065, OCE0745606
NSUWorks Citation
Jeremy Vaudo and Michael Heithaus. 2011. Dietary Niche Overlap in a Nearshore Elasmobranch Mesopredator Community .Marine Ecology Progress Series : 247 -260. https://nsuworks.nova.edu/occ_facarticles/853.
Comments
©Inter-Research 2011