REPORT OF COMMITTEE ON NEW ZEALAND 

 FOOD FISHES. 



The Committee, consisting of Messrs. C. W. Chamberlain, D. 

 Barron, and Geo. M. Thomson, was appointed at the last meeting of 

 the Association " to investigate the local conditions affecting the food 

 supply of food fishes of New Zealand seas at the fish hatchery at Porto- 

 bello.'' 



The station was formally opened on January 13th, 1904, by Pro- 

 fessor T. W. Edgeworth David, President of the Association, but work 

 was not begun till later in the year. The Marine Hatchery Board was 

 very fortunate in the selection of Mr. T. Anderton as curator, as he has 

 entered into the spirit of research with great zeal. 



The methods adopted to carry out the work of the Committee have 

 been (1) to collect and record, as far as possible, the contents of the 

 stomachs of various species of fish taken ; (2) to note the occurrence, 

 distribution, and life histories of the living organisms which compose 

 the food of fishes ; and (3) to keep daily records of the temperatures 

 of the air, of the ponds, and of the water of the harbor. From the 

 limited means at the disposal of the Board and Committee it was only 

 possible to carry out these methods very imperfectly ; still, a good 

 beginning has been made. Very considerable assistance has been 

 afforded by Mr. F. J. Sullivan, owner of the steam trawler Express, 

 who afforded Mr. Anderton the opportunity of going out with the 

 steamer at any time she was at work, and also placed facilities in his 

 way for securing the ova of fish, any rare or unknown specimens which 

 were taken in the trawl nets, and of examining the stomachs of the 

 fishes caught. The engineer of the trawler also assisted by keeping, 

 for a time, a record of the temperatures of the surface water of the 

 harbor and of the ocean six miles off Otago Heads. At such times as 

 the work at the station permitted and the weather was favorable, Mr. 

 Anderton was out about once a week with the trawler, and made good 

 use of his time. 



One of the most interesting facts ascertained in connection with 

 these observations is that while the temperature of the ocean — even in 

 midwinter — does not fall below 9° C. (= 48° F.), that of the shallower 

 waters in enclosed bays, such as that of Otago Harbor, frequently falls 

 as low as 3° C. (37°-4 F.). Of course, this chilling of the tidal waters 

 is greatly intensified in the shallow ponds at the hatchery, where at 

 times during the winter of 1905 the temperature fell to 0° C. It was 

 ascertained that certain species — such as the blue cod {Parapercis 

 colias, Forster) — could not survive exposure to this temperature. 

 Such chilling of the shallower coastal waters evidently causes this and 

 probably many other species to move out into deeper waters at the 

 commencement of winter. In cold weather also it was noticed that 

 this species does not take food. 



