Skip to main content

Using the composite variables of reproductive morphology, histology and steroid hormones to determine age and size at sexual maturity for the thorny skate Amblyraja radiata in the western Gulf of Maine

Buy Article:

$51.00 plus tax (Refund Policy)


Age at size was linked to sexual maturity in 77 male and 93 female thorny skates Amblyraja radiata from the western Gulf of Maine using three criteria: 1) gross reproductive morphology, 2) histology and 3) steroid hormone concentrations. Age-bias plots and the coefficient of variation from vertebral band counts suggested that the ageing method represented a non-biased and precise approach to the age assessment of A. radiata. Maturity ogives for males, based on data gathered for clasper length, circulating testosterone concentrations and proportion of mature spermatocysts within the testes, predicted that 50% maturity occurred at a total length (LT) of 865 mm and c. 10·90 years of age. For females, maturity ogives, based on data gathered for ovary mass, shell gland mass, follicle size and circulating oestradiol concentrations, predicted that 50% maturity occurred at 875 mm LT and c. 11·00 years of age. Collectively, the results suggest that analysis of several contemporaneous reproductive variables offers an accurate determination of sexual maturity in the thorny skate.

Keywords: elasmobranch; life history; oestradiol; spermatogenesis; testosterone

Document Type: Regular Paper


Affiliations: 1: Zoology Department, University of New Hampshire, Spaulding Hall, 46 College Road, Durham, NH 03824, U.S.A., 2: Yankee Fisherman’s Cooperative, P. O. Box 2240, Seabrook, NH 03874, U.S.A. 3: Department of Animal and Nutritional Sciences, University of New Hampshire, Kendall Hall, 129 Main Street, Durham, NH 03824, U.S.A.

Publication date: 2006-11-01

  • Access Key
  • Free ContentFree content
  • Partial Free ContentPartial Free content
  • New ContentNew content
  • Open Access ContentOpen access content
  • Partial Open Access ContentPartial Open access content
  • Subscribed ContentSubscribed content
  • Partial Subscribed ContentPartial Subscribed content
  • Free Trial ContentFree trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more