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A. Vedel Taming 



SEASONAL DISTRIBUTION OF FRY 



Southwestern North Atlantic. To find the breeding areas of a species, the smallest 

 larval stages are the most important, because these are carried by currents alone for 

 comparatively short distances from the spawning area itself. Therefore we will 

 consider only those specimens in postlarval stages smaller than 20 mm in length, 

 in examining the seasonal distribution. As shown below, it is unUkely that any of 

 the postlarval stages were taken in depths greater than 200 metres. Certainly they 

 belong to the warmest, upper water layers, so that we need only consider the nets 

 which fished with 600 metres of wire out or less, because these nets undoubtedly 

 fished only in the upper 200 metres of the sea. 



Since various sizes of nets were used, the fishing time was calculated as the number 

 of hours a stramin ring-net 2-metres in diameter was towed.* In the areas where all 



Fig. 4. Records of Xiphias postlarvae obtained during the cruise, April-July 1920. • positive stations, 

 • negative stations. Areas with surface temperatures below 24° C indicated. 



the catches were made in the western North Atlantic Ocean, namely in the Carib- 

 bean Sea and that part of the Sargasso Sea between 15° N and 30° N and west of 

 40° W, there have been about 1690 2-metre-stramin-net hours fishing in the upper 

 200 metres of the sea. 



From Table I, it can be seen that the postlarval stages smaller than 20 mm in length, 

 which are mostly less than a month old, occur practically throughout the year. Even 

 the smallest postlarval stages of 5-8 mm in length are found in nearly every month 

 of the year. With so httle material, no definite estimate of a peak season can be given. 

 However, omitting the catches for July-September, when Httle fishing was under- 

 taken in the area, and considering only those months when more than 100 hours 

 or more of fishing actually took place, one notices that the biggest catches occurred 

 in February-March- April. The preceding months show a consistent increase towards 



*One hour's fishing with this gear (S200) is calculated as equal to 2 hours with a U m stramin net 

 (S150) or silk net (P150), and to 4 hours with a 1 m stramin net (SlOO) or silk net (PlOO). 



