SS1.02 Geochemical Tracers in Calcified Structures: Implications for Fisheries Research
Date: Tuesday, June 11, 2002
Time: 5:00:00 PM
Location: Carson A
 
PattersonWF, University of South Alabama, Mobile, USA, wpatterson@disl.org
Cowan, J, H, Louisiana State University, Baton Rouge, USA, jhcowan@lsu.edu
Wilson, C, A, Louisiana State University, Baton Rouge, USA, cwilson@lsu.edu
Chen, Z, , Old Dominion University, Norfolk, USA, zchen@odu.edu
 
OTOLITH ELEMENTAL SIGNATURES OF AGE-0 RED SNAPPER NURSERY AREAS IN THE NORTHERN GULF OF MEXICO FROM 1996 THROUGH 2000
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Juvenile red snapper were sampled from five areas in the northern Gulf of Mexico from 1996 through 2000. In the laboratory, otoliths were extracted from fish, cleaned, and put into solution. Otolith solutions were analyzed with a magnetic sector-inductively coupled plasma-mass spectrometer for the concentrations of nine elements: B, Ba, Ca, K, Mg, Mn, Na, P, and Sr. Otolith elemental signatures were significantly different among nursery areas (MANOVA: Pillai’s Trace, p < 0.001) and among years (MANOVA: Pillai’s Trace p < 0.001). Linear discriminant function analyses (LDFAs), therefore, were computed for each year class separately to deduce the efficacy of using otolith elemental signatures as natural tags of red snapper nursery areas. Overall classification accuracies from LDFAs were 91, 85, 77, 82, and 74% for the 1996 through 2000 year classes, respectively. Classification accuracies from LDFAs increased (mean = 86%) when samples from the five nursery areas were grouped into three regions (north central Gulf, northwest Gulf, and southwest Gulf). Results indicate that otolith elemental signatures are effective natural tags of red snapper nursery areas.