CSIRO Publishing Books Journals About Us Shopping Cart You are here: Journals > Marine & Freshwater Research   
Marine & Freshwater Research
  Advances in the Aquatic Sciences
 
Search
 
 
  Advanced Search
   

Journal Home
About the Journal
Editorial Board
Contacts
Content
Online Early
Current Issue
Just Accepted
All Issues
Special Issues
Sample Issue
For Authors
General Information
Instructions to Authors
Submit Article
Open Access
For Referees
General Information
Review Article
Referee Guidelines
Early Career Referee Mentoring
For Subscribers
Subscription Prices
Customer Service
Print Publication Dates

 Early Alert
Subscribe to our email Early Alert or RSS feeds for the latest journal papers.

 Connect with us
facebook   youtube

 

Article << Previous     |     Next >>   Contents Vol 58(11)

The use of caudal thorns for ageing Raja undulata from the Portuguese continental shelf, with comments on its reproductive cycle

Teresa Moura A D, Ivone Figueiredo A, Inês Farias A, Bárbara Serra-Pereira B, Rui Coelho C, Karim Erzini C, Ana Neves B, Leonel Serrano Gordo B

A Departamento de Recursos Marinhos, IPIMAR, Ave. Brasília, 1449-006 Lisboa, Portugal.
B Departamento de Biologia Animal and Instituto de Oceanografia, Faculdade de Ciências da Universidade de Lisboa, Bloco C2, Campo Grande, 1749-016 Lisboa, Portugal.
C Centro de Ciências do Mar (CCMAR), Faculdade de Ciências do Mar e do Ambiente, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal.
D Corresponding author. Email: tmoura@ipimar.pt
 
PDF (448 KB) $25
 Export Citation
 Print
  


Abstract

The present study focuses on age estimation, with reproductive information contributing to the better understanding of the growth and the biology of Raja undulata. In the age and growth study, two calcified structures were used: caudal thorns and central vertebra. Results of readings showed that there were no significant differences in age estimates between the two structures. Both von Bertalanffy and Gompertz growth models were fitted to size-at-age data by sex and geographical area. No significant differences were found between sexes for the two models but significant differences were found between geographical areas (P = 0.05). The Gompertz growth function was selected as the best model to describe R. undulata growth because it presented the best fit and the most reasonable biological estimates. Reproductive analysis indicates one annual breeding season for R. undulata. The differences found in the estimates of length at first maturity between geographical areas (TL50% = 838 mm in Peniche and 762 mm in Algarve for females and TL50% = 781 mm in Peniche and 736 mm in Algarve for males), together with the regional differences found between growth parameters estimates (P = 0.05), may reflect the existence of different local populations of R. undulata on the Portuguese continental shelf.

Keywords: growth, Portugal, reproduction, vertebrae.


   
Subscriber Login
Username:
Password:  

    


 
Top  Email this page
 
Legal & Privacy | Contact Us | Help

CSIRO

© CSIRO 1996-2012