270 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



EXPERIMENTS WITH MARKED PLAICE 

 DURING 1912. 



By Jas. Johnstone, B.Sc 



Three experiments were made in 1912. The first one 

 dealt with 212 plaice, which were caught in the neigh- 

 bourhood of Nelson Buoy on 5th June, and were 

 liberated on the same date. At the end of the year 26 

 of these fishes had been returned. 



The second experiment was made on 3rd October, 

 when 153 plaice were caught and liberated, also in the 

 neighbourhood of Nelson Buoy. At the end of the year 

 26 of these plaice had also been returned. 



The third experiment was made in Luce Bay on 

 22nd October. At the end of a day's trawling for 

 spawning plaice for Piel and Port Erin Hatcheries about 

 45 of the smaller plaice caught were marked and 

 liberated. At the end of the year only one of these fish 

 had been returned. 



It is, of course, too soon to attempt to summarise 

 the results of these experiments, since the fish marked 

 will continue to be returned for another year. The 

 migrations made are, however, charted on pp. 303-5, 

 and are there discussed in relation to the movements of 

 plaice in general which accompany changes of sea- 

 temperature. Tables showing the details of the 

 recaptures for the year 1912 are given here. 



