ska Fisheries laboratory. 79 



special spots for spawning, it is difficult to say what — 

 besides distance from land, a fair depth of water, and 

 abundance of food both on bottom and surface — these factors 

 are in the present case. In co-operation with Mr. Dawson, 

 it is proposed during the coming spawning season to 

 make some expeditions to this ground, when no doubt 

 further information both as to the kinds, numbers, and 

 sizes of the spawning fish, and also as to their surrounding 

 conditions, will be obtained. 



We have also while dredging from Port Erin come upon 

 a spawning ground on the other side of the Isle of Man. 

 It is 5 miles west of Dalby, the depth is 30 fathoms and 

 the bottom is what the trawlers call "reamy," i.e., a, 

 mixture of sand and mud. Here in the latter half of June 

 we found Sole, Turbot and Brill all spawning. 



Vitality Experiments. 



In connection with the enormous destruction of imma- 

 ture food fishes by shrimp nets discussed in the last report, 

 and the disputed question as to whether it is much use 

 returning the more or less exhausted fish to the sea, it was 

 suggested (p. 27) that investigations should be carried on 

 from the " John Fell " on the same lines as those started 

 by the Scottish Fishery Board on their steamer " Garland." 

 This has been done during the past year, and we have 

 now statistics showing the results of a number of experi- 

 ments made on fish taken both with the shrimp trawl and 

 and also with the fish trawl. 



The mode of procedure has been as follows : — The fish 

 are taken from the net, measured, and the species noted, 

 and are then put into a fixed tub (about 3x2 feet) through 

 which is kept running by means of the hose a constant 

 stream of sea- water. They are left in the tub from half- 

 an-hour to an hour, or even two hours, and then the 



