Natal origin of Atlantic bluefin tuna (Thunnus thynnus) from Canadian waters based on otolith [delta]^sup 13^C and [delta]^sup 18^O

Increased knowledge of stock mixing and migration of Atlantic bluefin tuna (Thunnus thynnus) is required to properly manage and conserve declining populations. Here, we predicted the nursery origin of giant bluefin tuna (n = 224) present in samples from Canadian waters using stable ...C and ...O iso...

Full description

Saved in:
Bibliographic Details
Published in:Canadian journal of fisheries and aquatic sciences 2010-03, Vol.67 (3), p.563
Main Authors: Schloesser, Ryan W, Neilson, John D, Secor, David H, Rooker, Jay R
Format: Article
Language:English
Subjects:
Comparative analysis
Fish migration
Fish stocking
Isotopes
Knowledge
Maximum likelihood method
Otoliths
Tuna
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Increased knowledge of stock mixing and migration of Atlantic bluefin tuna (Thunnus thynnus) is required to properly manage and conserve declining populations. Here, we predicted the nursery origin of giant bluefin tuna (n = 224) present in samples from Canadian waters using stable ...C and ...O isotopes in otoliths. The isotopic composition of milled otolith cores (corresponding to the first year of life) of giant bluefin tuna from three decades (1970s, 1980s, 2000s) and three regions within or adjacent to the Gulf of St. Lawrence was compared with otolith ...C and ...O of yearling bluefin tuna collected from eastern (Mediterranean Sea - eastern Atlantic, n = 136) and western (western Atlantic, n = 103) nurseries. Maximum likelihood estimates indicated that greater than 99% of bluefin tuna in our Canadian samples originated from the western nursery. No significant differences in estimates of origin for bluefin tuna were detected among decades or among regions, suggesting little to no mixing of eastern and western populations in the Canadian samples examined. These findings justify the use of catch rates from the Gulf of St. Lawrence area as an index of abundance for the oldest members of the western population. (ProQuest: ... denotes formulae/symbols omitted.)
ISSN:0706-652X
1205-7533