Marine & Environmental Sciences Faculty Articles

Broad Geographic Distribution of Roundscale Spearfish (Tetrapturus georgii) (Teleostei, Istiophoridae) in the Atlantic Revealed by DNA Analysis: Implications for White Marlin and Roundscale Spearfish Management



Document Type


Publication Title

Fisheries Research



Publication Date



Fisheries management; Species identification, Kajikia albida, Mitochondrial DNA, Billfish


The recent validation of the roundscale spearfish (Tetrapturus georgii) within the western North Atlantic has introduced new complexities in the management of the overfished white marlin (Kajikia albida) in this region due to historical and contemporary misidentification between the two morphologically similar species. Compounding the management challenge for white marlin, which is currently assessed as a single Atlantic-wide stock, is an unclear picture of the extent of the roundscale spearfish's overall Atlantic distribution. By using genetic tools (mitochondrial DNA ND4L-ND4 locus sequences) for species identification, we confirm that the roundscale spearfish has a much broader distribution than previously known, including the central North Atlantic and much of the western South Atlantic to at least 28°52′S. This much wider Atlantic distribution of the roundscale spearfish sympatric with its morphologically similar congeners, the white marlin and longbill spearfish (Tetrapturus pfluegeri), raises further management complexities: it increases the geographic scale for species misidentification in catch records that form the basis for stock assessments and uncertainty in currently accepted white marlin biological parameters. Additional vigilance in obtaining accurate species identification by improved fishery onboard observer training and incorporation of genetic tools is recommended for informing management of white marlin, longbill spearfish and roundscale spearfish throughout the Atlantic.





First Page


Last Page



©2012 Elsevier B.V. Published by Elsevier B.V. All rights reserved.

Additional Comments

This work was supported by funding from NOAA/NMFS SEFSC, a National Science and Engineering Research Council of Canada Graduate Fellowship (AMB), The Guy Harvey Ocean Foundation, The Brazilian Ministry of Fisheries and Aquaculture, Universidade de Mogi das Cruzes, Unidade de Biotecnologia, FAPESP (proc. 2009/54660-6), and Agencia Paulista de Tecnologia dos Agronegócios, Instituto de Pesca.

This document is currently not available here.

Peer Reviewed

Find in your library