Volumes

by publication dates
August 2024 (1)
December 2023 (2)
May 2023 (1)
October 2022 (1)
September 2022 (2)
August 2022 (1)
April 2022 (1)
December 2021 (1)
November 2021 (1)
October 2021 (1)
September 2021 (1)
January 2021 (1)
December 2020 (1)
November 2020 (1)
October 2020 (1)
July 2020 (1)
June 2020 (2)
January 2020 (1)
May 2019 (1)
April 2019 (1)
March 2019 (1)
January 2019 (1)
January 2018 (1)
December 2017 (1)
October 2017 (1)
July 2017 (1)
December 2016 (2)
November 2016 (1)
October 2016 (1)
February 2016 (1)
December 2015 (4)
September 2015 (2)
July 2015 (1)
March 2015 (1)
December 2014 (3)
July 2014 (2)
May 2014 (1)
December 2013 (4)
October 2013 (1)
March 2013 (1)
January 2013 (1)
December 2012 (6)
October 2012 (2)
July 2012 (1)
January 2012 (1)
December 2011 (3)
November 2011 (1)
October 2011 (1)
September 2011 (1)
August 2011 (1)
May 2011 (1)
March 2011 (1)
February 2011 (1)
August 2010 (1)
June 2010 (2)
May 2010 (2)
April 2010 (1)
March 2010 (2)
February 2010 (2)
December 2009 (1)
October 2009 (6)
September 2009 (2)
August 2009 (2)
July 2009 (1)
April 2009 (1)
February 2009 (7)
January 2009 (5)
December 2008 (1)
October 2008 (1)
September 2008 (4)
August 2008 (4)
June 2008 (1)
May 2008 (1)
April 2008 (1)
February 2008 (4)
January 2008 (3)
December 2007 (5)
November 2007 (2)
August 2007 (1)
June 2007 (2)
May 2007 (4)
March 2007 (3)
February 2007 (1)
January 2007 (1)
November 2006 (1)
October 2006 (1)
September 2006 (3)
June 2006 (1)
May 2006 (1)
April 2006 (2)
February 2006 (2)
January 2006 (2)
December 2005 (6)
November 2005 (1)
October 2005 (5)
September 2005 (1)
June 2005 (1)
April 2005 (3)
March 2005 (16)
February 2005 (4)
January 2005 (6)
December 2004 (2)
November 2004 (7)
October 2004 (1)
September 2004 (12)
December 2003 (4)
October 2003 (37)
March 2003 (13)
December 2002 (7)
December 2001 (7)
December 2000 (34)
October 1999 (21)
November 1998 (6)
October 1998 (18)
December 1997 (28)
April 1997 (7)
October 1996 (13)
September 1996 (1)
April 1996 (9)
October 1994 (8)
July 1994 (9)
December 1993 (1)
December 1992 (26)
January 1992 (9)
February 1991 (9)
December 1990 (3)
December 1989 (8)
October 1989 (9)
December 1988 (9)
December 1987 (11)
December 1986 (11)
December 1985 (10)
June 1985 (11)
November 1984 (12)
January 1984 (18)
July 1983 (1)
December 1982 (12)
May 1982 (9)
November 1981 (12)
November 1980 (12)


JNAFS

14

D. P. Swain, T. Hurlbut and H. P. Benoît

Fisheries and Oceans Canada, Gulf Fisheries Centre, P. O. Box 5030
343 University Avenue, Moncton, New Brunswick E1C 9B6

 

Publication (Upload) date: 14 Jun 2005

 

SWAIN, D. P., T. HURLBURT, and H. P. BENOÎT. 2005. Changes in the abundance and size of skates in the Southern Gulf of St. Lawrence, 1971-2002. J. Northw. Atl. Fish. Sci., 36: 19-30. https://doi.org/10.2960/J.v36.m552

 

Abstract

Three species of skates commonly occur in the southern Gulf of St. Lawrence: thorny skate Amblyraja radiata, winter skate Leucoraja ocellata, and smooth skate Malacoraja senta. Trends in their abundance and size are described using data from annual bottom-trawl surveys conducted each September since 1971. Biomass and the abundance of mature skates decreased over the 1971–2002 period, by 80–90% for thorny and winter skates, and to a lesser degree for smooth skates. Abundance of juvenile thorny and smooth skates increased from the mid-1980s to a peak in the mid-1990s, and then declined in the late1990s. Mean length decreased by 20–30% during the 1980s for each of the three species. The increase in the abundance of juvenile skates in the 1990s coincided with a collapse in the biomass of large-bodied demersal teleost fishes, a dramatic decline in fishing effort, a cooling of the cold intermediate layer in the southern Gulf and decreasing abundance of mature skates. The decline in the abundance of large skates may be an effect of fishing, though reported landings of skates have been low. These results for the southern Gulf of St. Lawrence contrast those observed on Georges Bank and in the North Sea, where small elasmobranch species that were not targeted by fisheries increased in biomass as the biomass of heavily exploited groundfish stocks declined.

Key words: elasmobranchs, indirect effects of fishing, non-target species, population declines, species replacement

PDF

Download Citation Data

 


Citation to clipboard

Reference management software (Endnote, Mendeley, RefWords, Zotero & most other reference management software)

LaTex, BibDesk & other specific software
Citation: SWAIN, D. P., T. HURLBURT, and H. P. BENOÎT. 2005. Changes in the abundance and size of skates in the Southern Gulf of St. Lawrence, 1971-2002. J. Northw. Atl. Fish. Sci., 36: 19-30. https://doi.org/10.2960/J.v36.m552
Actions: E-mail | Permalink |