CSIRO Publishing blank image blank image blank image blank imageBooksblank image blank image blank image blank imageJournalsblank image blank image blank image blank imageAbout Usblank image blank image blank image blank imageShopping Cartblank image blank image blank image You are here: Journals > Marine & Freshwater Research   
Marine & Freshwater Research
Journal Banner
  Advances in the Aquatic Sciences
 
blank image Search
 
blank image blank image
blank image
 
  Advanced Search
   

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

blue arrow e-Alerts
blank image
Subscribe to our Email Alert or RSS feeds for the latest journal papers.

red arrow Connect with us
blank image
facebook twitter youtube

 

Article << Previous     |     Next >>   Contents Vol 56(1)

Reproductive biology, size and age compositions and growth of the batoid Urolophus paucimaculatus, including comparisons with other species of the Urolophidae

William T. White A B, Ian C. Potter A

A Centre for Fish and Fisheries Research, School of Biological Sciences and Biotechnology, Division of Science and Engineering, Murdoch University, Murdoch, WA 6150, Australia.
B Corresponding author. Email: wwhite@murdoch.edu.au
 
PDF (311 KB) $25
 Export Citation
 Print
  


Abstract

The biology of Urolophus paucimaculatus in south-western Australian waters has been examined and compared with that of the co-occurring Urolophus lobatus, Trygonoptera personata and Trygonoptera mucosa. These four species represent the only two genera of the Urolophidae. Urolophus paucimaculatus conceives in early/mid-summer and gives birth in late spring/early summer, closely paralleling the situation with U. lobatus. Although Trygonoptera species likewise have a 10–12-month gestation period, they conceive and give birth in late autumn to mid-winter. The marked intergeneric differences in birth time help account for pronounced intergeneric differences in the diets of their newly born young. By birth, Urolophus paucimaculatus attains ~50% of its asymptotic size. The relatively large mean disc width of the four urolophids at birth, i.e. 105–128 mm, accounts for the small litters of these species (1–2 young per litter). Size at maturity and maximal size and age of each species are greater for females than males and are greater for Trygonoptera than Urolophus species. The growth of U. paucimaculatus and the other urolophids throughout pre- and postnatal life can be described by a single smooth growth curve. The maintenance of a constant pattern of growth from conception is remarkable because the diet and behaviour of these elasmobranchs changes radically at parturition.

   
Subscriber Login
Username:
Password:  

    
Legal & Privacy | Contact Us | Help

CSIRO

© CSIRO 1996-2014