of the Fishery Board for Scotland. 



317 



APPENDIX F. — No. IX. 

 THE FOOD OF THE WHITING {Gadus merlangus). 

 By J. Duncan Matthews. 



In connection with the important subject of the food supply of our useful 

 fishes, less seems to have been done in the way of a systematic examina- 

 tion of the normal food supply of the whiting than of the cod and 

 haddock. This, to some extent, probably arises partly from the whiting 

 not being so common as these other white fish, and partly owing to their 

 being generally sold as fresh fish, the latter circumstance interfering with 

 the ready examination of a large number, and over a continuous period. 



The following Table is prepared from the examination of about 400 

 stomachs procured by the Fishery officers from wmitings caught on the 

 East Coast of Scotland, mostly during the autumn and winter months. 

 Though probably giving a fairly accurate statement of the whiting's main 

 food supply, the list is yet scarcely extensive enough either as to numbers 

 examined, or to season and locality, as to be entirely conclusive. 



Yarrell states that the whiting is a voracious feeder, seizing indiscrimin- 

 ately any molluscs, worms, small Crustacea, or young fishes. Day also 

 refers to its voracity, giving as its food small fish, Crustacea, and any 

 animal substances it can obtain. 



My examination does not support these accounts of the indiscriminate 

 appetite of the fish. It will be seen from an examination of the following 

 list, that the whiting's food supply seems to be of a much less variable 

 nature than has been stated. It may be said to be almost entirely limited 

 to small fish and Crustacea. Of the echinodermata, which form so large 

 a proportion of the haddock's food, not a single example was found in 

 the whitings examined by me, although they were to a large extent caught 

 on the same grounds, and at the same time, as haddocks which were found 

 to be feeding, to a large extent, on brittle stars, and less commonly on 

 worms and molluscs. 



In one case there were some small echinoderms mixed up with fi*h 

 remains in the whiting's stomach and these might have been thought 

 to have been directly consumed by the whiting. The condition in other 

 whitings from the same take showed conclusively that this was not so. 

 In these others were found the same small white fish, but in a less 

 digested condition, and these latter had still their stomachs intact. On 

 examination these small fish stomachs were found packed full of identi- 

 cally the same echinoderms as those found among the fish remnants in the 

 whiting referred to. It was evident, therefore, that this whiting had not 

 been feeding on echinodermata, but that these were in its stomach only 

 from the secondary cause of having escaped from the partially-digested 

 stomach of the whiting's prey. 



It seems doubtful whether the pieces of the common mussel occasion- 

 ally found in the whitings' stomachs, recorded below, may not, to some 

 extent, be accounted for by their having swallowed the bait on the lines 

 on which they were caught, for all the cases in which the mussel occurred 

 were line-caught fish. The fact that they take this bait is not necessarily 

 conclusive evidence that the mussel forms a part of their natural food. 

 It certainly seems not to do so to any considerable extent, but that they 

 occasionally do feed on the mussel seems probable from the contents of 

 stomach No. 268, in which were found eight (or parts of eight) mussels, 

 which were scarcely likely to have been all taken from hooks. In no 

 case, however, was any part of the shell found, so that if they are not 

 eaten as 1 bait,' the shells must be completely dissolved before much 

 action on the flesh occurs. It will be noted, too, that, except for the 



