360 



DISCOVERY REPORTS 



Although we took only ahout a thousand of this species during the three surveys, we have strong 

 evidence that many more large hauls of it could have been obtained in summer (when it tends to shoal 

 inshore), had we been concentrating upon it as a commercial fishing vessel would have been able to 

 do, instead of sampling the whole area. 



During the three trawling surveys, S. maciilatus was captured in the ' Trawl + accessory nets' at 

 fifty-two stations, as shown below. It was never taken by us with ' Other gear ' :^ 



The distribution of these catches at different seasons of the year is charted in Fig. 44. From this 

 it can be seen that in spring (a) a few Stromateus were taken on the shelf in the northern region, and 

 that there a few were already right inshore. The species was not observed on the single line of stations 

 worked in the intermediate region, nor at a couple of odd stations worked farther south at that season. 

 From this it may be concluded that in spring some shoreward movement has begun, but probably 

 little southward movement. 



In summer {b) the species was much more frequently taken and in very much larger numbers, 

 especially to the southward. Several really good hauls of Stromateus were made inshore, from Cape 

 Virgins northwards to a point off Puerto san Julian. Moderate numbers were taken at several stations 

 on the plain of the shelf, but the species was not taken in the deeper water to the southward. It was 

 also absent from all but one of the catches at the outermost stations (those worked nearest to the shelf- 

 edge) on the northern and intermediate lines, and from the immediate vicinity of the Falkland Islands. 

 It would seem clear that the species works southwards inshore during summer, and reaches maximum 

 concentration (shoaling) at that season. 



In autumn {c) some Stromateus were caught still inshore in Grande Bay in the southern region, 

 but this was in only one of the two years for which we have autumn data, and the location of most of 

 the catch was farther offshore (though still on the plain of the shelf) and to the north. The distribution 

 IS clearly compatible with the hypothesis of dispersal of the southern summer inshore shoals in that 

 direction. 



Stromateus was captured at two stations only during the winter survey {d). These were right offshore 

 on the shelf edge in the intermediate region, and the numbers of individuals were but one and four 

 respectively. None was taken at any of the numerous stations worked on the plain of the shelf and 

 to the southward at this season. These observations clearly point to continued dispersal offshore and 

 to the north. 



Perhaps the ' spotted pomfret ' should be regarded as a semi-pelagic wanderer in winter. Its seasonal 



1 Cf. Goode's remark of Poronotiis triacantlius: 'it has never been known to take a hook.' Quite recently, however, some 

 Ime-caught Poronotus were reported from Florida. 



