Age and growth estimates of the thorny skate (Amblyraja radiata) in the western Gulf of Maine

James A. Sulikowski, Jeff Kneebone, Scott Elzey, Joe Jurek, Patrick D. Danley, W. Huntting Howell, Paul C.W. Tsang

Research output: Contribution to journalArticlepeer-review

52 Scopus citations


The northwest Atlantic population of thorny skates (Amblyraja radiata) inhabits an area that ranges from Greenland and Hudson Bay, Canada, to South Carolina. Despite such a wide range, very little is known about most aspects of the biology of this species. Recent stock assessment studies in the northeast United States indicate that the biomass of the thorny skate is below the threshold levels mandated by the Sustainable Fisheries Act. In order to gain insight into the life history of this skate, we estimated age and growth for thorny skates, using vertebral band counts from 224 individuals ranging in size from 29 to 105 cm total length (TL). Age bias plots and the coefficient of variation indicated that our aging method represents a nonbiased and precise approach for the age assessment of A. radiata. Marginal increments were significantly different between months (Kruskal-Wallis P<0,001); a distinct trend of increasing monthly increment growth began in August. Age-at-length data were used to determine the von Bertalanffy growth parameters for this population: Lχ = 127 cm (TL) and k = 0.11 for males; L χ = 120 cm (TL) and k = 0.13 for females. The oldest age estimates obtained for the thorny skate were 16 years for both males and females, which corresponded to total lengths of 103 cm and 105 cm, respectively.

Original languageEnglish (US)
Pages (from-to)161-168
Number of pages8
JournalFishery Bulletin
Issue number1
StatePublished - Jan 2005
Externally publishedYes

ASJC Scopus subject areas

  • Aquatic Science


Dive into the research topics of 'Age and growth estimates of the thorny skate (Amblyraja radiata) in the western Gulf of Maine'. Together they form a unique fingerprint.

Cite this