SEA-FISHERIES LABORATORY. 125 
plaice inhabiting the Barrow Channel and neighbourhood 
have been a practically stationary fish population during 
the first three quarters, at least, of the year 1908. Asa 
matter of fact, relatively enormous catches of plaice have 
been made on these grounds during the first half of the 
year. One tide’s catch, made by one man working several 
stake nets, consisted of over half a ton of plaice. ‘There 
were apparently great areas of sea-bottom in this locality 
covered by small, growing mussels, and this abundance of 
food led to the aggreeation of the plaice in its neighbour- 
hood. ‘Towards the end of the year the fish of A@e-group 
III have apparently begun to move out into deeper water, 
but throughout eight or nine months they have practically 
remained in the one locality. 
This conclusion is supported by a study of the Age- 
groups of representative samples of plaice taken from the 
stake nets on Roosebeck Scars. ‘These results are given in 
the table on page 126, which deals with the examination of 
four lots of fish. 
It will be seen that the plaice examined in May 
belonged for the most part to the group over one and less 
than two years of age. In June, however, Age-group I 
practically disappears and the fish then belong to the 
group over two and less than three years of age, and with 
a modal size of 19 centimetres. In September Age- 
group Lis also nearly absent, and the fish belong to Age- 
group Il, but the modal size now hes between 24 and 25 
centimetres. Again, in September Age-group II is the 
principal one represented, and the modal size is much 
about the same, perhaps a little greater. There are a few 
fishes in each catch belonging to Age-group III, but not 
many. Of course it might be the case that there was an 
immigration of plaice belonging to Age-groups II and III 
during the summer and autumn months, but I do not 
think this could have been extensive. 
