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Updated: Jul 12, 2026
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Basic Methods for the Study of Reproductive Ecology of Fish in Aquaria
Published on: July 20, 2017
Natal homing in a marine fish metapopulation
S R Thorrold1, C Latkoczy, P K Swart
1Department of Biological Sciences, Laboratory for Isotope and Trace Element Research, Old Dominion University, Norfolk, VA 23529, USA. sthorrold@whoi.edu
Science (New York, N.Y.)
|February 24, 2001
Summary
Marine fish origins are hard to track. Geochemical signatures in otoliths reveal weakfish natal homing, crucial for fisheries management and marine reserve design.
Area of Science:
- Marine biology
- Fish ecology
- Geochemistry
Background:
- Mark-recapture studies are difficult in marine environments for identifying fish origins.
- Understanding natal origins is vital for effective fisheries management and conservation strategies.
- Weakfish (Cynoscion regalis) are estuarine-spawning fish important to North American fisheries.
Purpose of the Study:
- To determine the natal origins of weakfish using natural geochemical signatures in otoliths.
- To assess the degree of spawning site fidelity in weakfish populations.
- To compare otolith-derived natal homing data with genetic population structure analyses.
Main Methods:
- Analysis of natural geochemical signatures (trace elements and isotopes) within otoliths (ear bones) of weakfish.
- Geochemical analysis to establish natal origins and track fish movements.
- Comparison of geochemical data with existing genetic data on weakfish population structure.
Main Results:
- Spawning site fidelity in weakfish ranged from 60% to 81%.
- These fidelity estimates are comparable to those observed in birds and anadromous fishes.
- Otolith geochemical data contrasted with findings from genetic analyses of weakfish population structure.
Conclusions:
- Natural geochemical signatures in otoliths provide a viable method for identifying marine fish natal origins.
- Weakfish exhibit significant spawning site fidelity, challenging previous assumptions based on genetic data.
- Findings underscore the importance of spatial processes in fisheries models and inform marine reserve planning.
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