Environmental Biology of Fishes 67: 253–261, 2003. © 2003 Kluwer Academic Publishers. Printed in the Netherlands. Stable isotopic composition of otoliths from tagged Pacific halibut

• Main Authors: Yongwen Gaoa, Richard J. Beamishc
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Bering Sea; Gulf of Alaska; Pacific; Alaska
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.553.9588; http://www.pac.dfo-mpo.gc.ca/science/people-gens/beamish/pdf_files/gao env bio fish 2003.pdf

Data from tagging studies and stable isotope ratio analyses (δ18O and δ13C) in otoliths of tagged Pacific halibut, Hippoglossus stenolepis, provided unique information about halibut distribution and area migration. The δ18O values of otoliths of individual halibut tagged in the Bering Sea and the Gulf of Alaska ranged from −0.5 ‰ to +1.0‰ VPDB (Vienna Peedee belemnite) in the first few years, but gradually increased to 2.0–2.5 ‰ VPDB when these tagged fish were recaptured as adults in waters off British Columbia. Similar isotopic variations were found in δ13C. Comparison of isotopic composition from the age-1 halibut (i.e., aragonite samples taken from the first annulus of otoliths) and the adult (ages ≥8) indicated that the ocean conditions between the Bering Sea and the northeast Pacific were markedly different over the tagging period, but the area boundaries between the Gulf of Alaska and British Columbia were not clear. We concluded that stable isotopic records in otoliths of tagged Pacific halibut were informative and particularly useful for details of subsequent movement of halibut between release and recovery.