Growth of Northwest Iberian juvenile hake estimated by combining sagittal and transversal otolith microstructure analyses
|Author(s)||Pineiro C1, Rey J2, De Pontual Helene3, Garcia A2|
|Affiliation(s)||1 : IEO, Vigo 36200, Spain.
2 : IEO, Malaga, Spain.
3 : IFREMER, Lab Sclerochronol Animaux Aquat STH LASAA, F-29280 Plouzane, France.
|Source||Fisheries Research (0165-7836) (Elsevier), 2008-09 , Vol. 93 , N. 1-2 , P. 173-178|
|WOS© Times Cited||24|
|Keyword(s)||NW Iberian waters, Seasonal variation, Daily growth, Otolith microstructure, Juvenile hake|
|Abstract||Daily growth of Atlantic juvenile hake from Northwest Iberia has been estimated employing a new approach combining analyses of transversal and sagittal sections of the otoliths along the ventral radius. Age of juvenile hake ranging from 3 to 25 cm collected during a spring 2002 survey was estimated. Somatic growth followed a power fit: Fish size (TL) = 3.3254*age(0.7336) (r(2) =0.87, p < 0.001, n = 76). yielding an average individual growth rate of 0.66 mm/day (0.06). The growth model indicates that after a year's life a juvenile can reach 25 cm. Otolith ventral radius ranged from 401 to 1842 mu m and daily increments were between 104 and 387. Fish growth and otolith growth were closely related (r(2) = 0.92 p < 0.001, n = 76). These first results of daily growth rates for the Southern stock corroborate the fast-growth hypothesis of this species. The evolution of increment widths from hatch dates onwards reveals important seasonal growth peaks during July-August and October-November. A comparison with prior data and discussion is also presented in the light of recent work on hake juveniles and tagging-recapture experiences. (c) 2008 Elsevier B.V. All rights reserved.|