Observations on the life history of the barndoor skate, Dipturus laevis, on Georges Bank (Western North Atlantic)

The barndoor skate (Dipturus laevis) has been reported to be close to extinction in parts of its northern range and is believed to be particularly vulnerable to fishing mortality due to its relatively large size. A lack of basic life history information, however, has hampered an accurate assessment...

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Bibliographic Details
Published in:Journal of Northwest Atlantic Fishery Science
Main Authors: Gedamke, Todd, DuPaul, William D., Musick, John A.
Format: Text
Language:unknown
Published: W&M ScholarWorks 2005
Subjects:
Online Access:https://scholarworks.wm.edu/vimsarticles/1763
https://scholarworks.wm.edu/context/vimsarticles/article/2761/viewcontent/19_gedamke.pdf
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Summary:The barndoor skate (Dipturus laevis) has been reported to be close to extinction in parts of its northern range and is believed to be particularly vulnerable to fishing mortality due to its relatively large size. A lack of basic life history information, however, has hampered an accurate assessment and management of north Atlantic populations. In an attempt to fill this void, information was collected from 2 310 specimens caught during commercial sea scallop dredging in the southern section of Georges Bank Closed Area II. Eighty-seven fish were determined to be mature from a visual inspection of reproductive tracts and the allometric growth of claspers, oviducal glands and developing ova. Sexual dimorphism was apparent in length at 50% maturity with females maturing at 116.3 cm and males at 107.9 cm. A preliminary analysis of 118 vertebrae indicates faster growth (k = 0.14 to 0.18) and younger female maturation (6.5 to 7.2 yr) than previously believed. Thus, resilience of the barndoor skate to overfishing may be higher than recently assumed.