Migrations of White Marlin and Blue Marlin 



in the Western North Atlantic Ocean — 



Tagging Results Since May, 1970 1 



FRANK J. MATHER, III, 2 JOHN M. MASON. JR., 2 and H. LAWRENCE CLARK 3 



ABSTRACT 



Migrations of white marlin, Tetrapturus albidus Poey, and blue marlin, Makaira nigricans Lacepede, 

 in the western North Atlantic Ocean are discussed in terms of tag returns obtained since the completion of 

 data collection for the paper by Mather, Jones, and Beardsley (1972) in May 1970. 



In the period May 1970-May 1972, 2,039 white marlin and 216 blue marlin have been released, and 

 70 tags from white marlin and 1 from a blue marlin have been returned. 



The migratory pattern which had been established for the stock of white marlin summering off the 

 middle Atlantic coast of the United States has been further supported by 54 of 60 new returns from fish 

 released in this area. The six others deviated from this pattern geographically or chronologically, or in 

 both respects. The ten remaining returns were from releases south of lat. 33°N. Five of these fitted with 

 previously observed patterns or individual migrations. The other five were local or scattered, but one of 

 them extended the range of recaptures southeastward to lat. 4°N, long. 40°W. 



As previously, times at liberty have been long, and the record has been increased to 58.7 mo. A new 

 calculation, incorporating much additional data, suggests that the annual mortality rate is between 23% 

 and 36%. 



The single blue marlin return is the first to show a significant migration — at least 750 nautical miles, 

 from the Bahamas to the Gulf of Mexico — and the dates of release and recapture support the theory of 

 separate populations of blue marlin in the North and South Atlantic. After 30 mo at liberty, this fish 

 weighed twice its estimated weight at release. 



Considerable new information on migrations of 

 white marlin and blue marlin in the western North 

 Atlantic Ocean has become available through tags 

 returned since the completion of the paper of 

 Mather, Jones, and Beardsley (1972) in May 1970. 

 In this paper we present these new data in detail, 

 and charts and tables summarizing the total ac- 

 cumulation of tag return data. The discussion cov- 

 ers agreements with, and differences from, the pre- 

 vious findings, and our present opinions about the 

 migrations of these fishes. The estimated mortality 

 rate of tagged and recaptured white marlin has also 

 been revised on the basis of the new data. 



'Contribution No. 2937, Woods Hole Oceanographic Institu- 

 tion, Woods Hole, MA 02543. 



2 Woods Hole Oceanographic Institution, Woods Hole, MA 

 02543. 



3 Dept. of Natural Resources, Cornell University, Ithaca, NY 

 14850. 



Little has been published on the tagging and mi- 

 grations of Atlantic marlins since the completion of 

 Mather et al. (1972), but we now refer to Earle 

 (1940) for an early tagging effort at Ocean City, 

 Maryland, which had been overlooked by the above 

 authors. 



METHODS AND MATERIALS 



Marlins and other oceanic fishes have been 

 marked with dart tags (Mather, 1963; Akyiiz, 1970) 

 by sport fishermen participating in the Cooperative 

 Game Fish Tagging Program of the Woods Hole 

 Oceanographic Institution (WHOI) since 1954. 

 Tags and tagging equipment are furnished by 

 WHOI, and release data are sent to WHOI. Unfor- 

 tunately, some difficulties in data retrieval have re- 

 sulted from failures of participants to send in re- 

 lease data. 



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