Graduate Thesis Or Dissertation

 

Age determination of corvina reina (Cynoscion albus) in the Gulf of Nicoya, based on otolith surface readings and microincrement analysis Público Deposited

Conteúdo disponível para baixar

Baixar PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/c821gn72v

Descriptions

Attribute NameValues
Creator
Abstract
  • The corvina reina (Cynoscion albus) is an important part of the artisanal fishery in the Gulf of Nicoya, Costa Rica. Stock assessment on this sciaenid species has been restricted to the use of length-based methods because of the lack of age data. Direct age determination methodologies for tropical species often encounter serious difficulties such as poorly defined hyaline and opaque zones and lack of adequate techniques of ageing. This thesis presents the results of an age-determination study of Cynoscion albus based on otolith surface readings and microincrement analysis. Age estimates were obtained from counts of hyaline zones from surface readings using the light microscope and from microincrement readings from cross sections of the otolith using the scanning electron microscope. Validation of age estimates from surface readings was based on a linear regression of the age estimates from surface readings on age estimates from integrated daily increment readings. Growth of the otolith was studied using linear and multivariate regression methods and the results were used to construct multivariate models for prediction of age. Consistent estimates of age and fish growth parameters were obtained from surface and microincrement analysis. This study showed that Cynoscion albus is a slow-growing fish (K = 0.121) and reaches a large size (L∞ = 127.5 cm) and therefore is likely to suffer overfishing in the Gulf of Nicoya fishery.
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Academic Affiliation
Non-Academic Affiliation
Subject
Declaração de direitos
Publisher
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi (Monochrome, 256 Grayscale) using Capture Perfect 3.0 on a Canon DR-9050C in PDF format. CVista PdfCompressor 4.0 was used for pdf compression and textual OCR.
Replaces

Relações

Parents:

This work has no parents.

Em Collection:

Itens