Population connectivity of red drum in the northern Gulf of Mexico

Marine Ecology Progress Series

Jay R. Rooker¹  Scott A. Holt¹  Gregory W. Stunz¹  Thomas J. Minello¹ 

关键词: Otolith chemistry;    Site fidelity;    Natal homing;    Residency;    Stable isotopes;    Stock identification;    Estuarine contribution;    Nursery origin;    Red drum;   

DOI  :  10.3354/meps08605

学科分类：海洋学与技术

来源: Inter-Research

【 摘 要 】

ABSTRACT: Stable carbon (δ¹³C) and oxygen (δ¹⁸O) isotope ratios in otoliths were used to assess the degree of connectivity between early life and adult habitats of red drum Sciaenops ocellatus in the northern Gulf of Mexico. Young-of-the-year (YOY) red drum were sampled over a 3 yr period from major estuaries along the Texas coast, and otolith δ¹³C and δ¹⁸O were quantified to determine whether chemical tags in otoliths were region specific. North to south gradients were pronounced for otolith δ¹³C and δ¹⁸O, with values being higher (enriched in the heavier isotope) for YOY red drum from southern estuaries relative to those in the north. Four distinct regional groups of YOY red drum were identified using otolith δ¹³C and δ¹⁸O: North (N), Sabine Lake and East Galveston Bay; North-Central (NC), Christmas Bay and Matagorda Bay; South-Central (SC), Aransas Bay and Redfish Bay; and South (S), Laguna Madre. Overall classification success to these regional nurseries was high for each year examined: 2001 (92%), 2002 (82%) and 2003 (90%). Mixed-stock analysis performed with age-2+ red drum collected in 2003 matched to the 2001 YOY baseline indicated that most of the sub-adult and adult red drum sampled in the S and SC regions were produced from the same areas (82 to 91%), with limited exchange between these regions. Mixing was more pronounced in the northern regions (N, NC), with a large percentage (35 to 42%) of individuals originating from the adjacent region to the south. Overall, the majority of sub-adult and adult red drum was collected within or near the same region occupied during the YOY period, suggestive of natal homing, retention within specific estuarine corridors, or lower survivability of recruits migrating from distant regions.

【 授权许可】

Unknown