title: Regional movement patterns of a small-bodied shark revealed by stable-isotope analysis.
abstract: This study used stable-isotope analysis to define the nearshore regional residency and movements of the small-bodied Australian sharpnose shark Rhizoprionodon taylori. Plasma and muscle δ(13) C and δ(15) N of R. taylori were collected from across five embayments and compared with values of seagrass and plankton from each bay. Linear distances between adjacent bays ranged from 30 to 150 km. There was a positive geographic correlation between R. taylori tissue and environmental δ(13) C values. Populations with the highest tissue δ(15) N were collected from bays that had the highest environmental δ(15) N values. These results suggest that R. taylori did not forage more than 100 km away from their capture location within 6 months to 1 year. The successful application of isotope analysis to define R. taylori movement demonstrates that this technique may be used in addition to traditional methods to study the movement of sharks, even within similar habitats across regionally small spatial scales (<100 km).
authors.affiliation: AIMS@JCU, Australian Institute of Marine Science & College of Marine and Environmental Sciences, James Cook University, Townsville, Qld 4811, Australia; Centre for Sustainable Tropical Fisheries and Aquaculture & College of Marine and Environmental Sciences, James Cook University, Townsville, Qld 4811, Australia.
authors.forename: S E M
authors.initials: SE
authors.lastname: Munroe
authors.forename: M R
authors.initials: MR
authors.lastname: Heupel
authors.forename: A T
authors.initials: AT
authors.lastname: Fisk
authors.forename: M
authors.initials: M
authors.lastname: Logan
authors.forename: C A
authors.initials: CA
authors.lastname: Simpfendorfer
mesh_terms: D000818:Animals; D001499:Bayes Theorem; D061006:Bays; D002247:Carbon Isotopes / Q000032:analysis; D017753:Ecosystem; D009043:Motor Activity; D009587:Nitrogen Isotopes / Q000032:analysis; D011793:Queensland; D012754:Sharks / Q000502:physiology*
chemical_list: D002247:Carbon Isotopes; D009587:Nitrogen Isotopes
keywords: Rhizoprionodon taylori; habitat connectivity; migration; residency; seagrass