25 

 MIGRATIONS OF FLAT FISH. 



By ALEXANDER MEEK. 



The o]3portunity was taken at the trawling experiments to 

 mark and Hberate a number of flat fish, principally dabs. I am 

 not enamoured of the plan of catching such for experimental 

 purposes in one place and liberating them in another, but the work 

 was so arranged that this was inevitable. 



The results may be grouped as {a) dabs caught during their 

 annual sojourn in inshore waterS; 11 examples ; (6) dabs caught 

 during their emigration from the inshore waters, 4 examples ; (c) 

 dabs caught during their immigration, one example ; and {d) dabs 

 which have migrated to the north — in all cases in the direction of 

 the locality of capture, 5 examples. The last are interesting since 

 they exhibit a northern migration which theoretically should take 

 place, but, unfortunately, there is the complication that they were 

 not liberated where caught. In the case of number 1302, the 

 migration was some 15 miles beyond the place of capture, and 21 

 miles from the place of liberation ; and the fish was caught at a 

 time when the majority of the dabs had not yet returned from 

 their winter migration. Another example which apparently had 

 remained in inshore waters after migrating 19 miles north is No, 

 1370. No. 1451 migrated from the place of liberation to the 

 place where it was originally captured. 



The recaptured plaice had evidently not been long in inshore 

 waters after the winter migration, see page 27. 



Since the above was printed I have received from the Board 

 particulars of recaptures relating to the dab (see page 28). The 

 results already tabulated bear evidence of a northern migration 

 of dabs which the considerations in the paper on the subject in 

 this report showed ought to take place. One of those now given, 

 No. 13^80 migrated northwards to St. Andrews, and according to 

 the information had spawned. It is possible therefore that a 

 northern race of dabs also occurs in the North Sea, or that 

 dabs when they become mature migrate northwards. 



