COUNCIL — APRIL 1912 — APPENDIX F — 108 — 



5) Consideration of the possible causes of decline in the stock of salmon. 



A. Obstacles in the way of salmon ascending the river, and of salmon and 

 their young migrating to the sea. 



B. Apparatus and methods of capture, especially with regard to how far 

 means detrimental to the stock — such as spearing the fish on the spawning-grounds — 

 are employed. 



. G. Harm or damage done to spawning-grounds, or to spawn or fry, by 



diverting or contaminating the water; also by ice. 



D. Contamination of the river or its tributaries by sewage outfalls, Cellu- 

 lose factories, Saw-mills, Sugar mills, Dye works or other industrial works; also 

 by timber rafts, and steeping of flax or hemp. 



Quantity and kind of timber rafted on the river or its tributaries, whether 

 pine or fir, etc: whether with bark or without; also the season of year for rafting, 

 stating also the length of time the timber remains in the water. 



It would also be desirable to study the effect on the fish of such contami- 

 nation, through for instance chemicals such as resinous acid, tanning, etc. contained 

 in the wood, as well as its effect on spawn and fry. This to be done not 

 only in the natural waters, but also in the laboratory. The effect contamination 

 of water by means of timber and bark, as regards diminution of oxygen should 

 also be studied. 



E. Examination should be made of the amount of damage done to sal- 

 mon by other fish preying on them or their eggs, by water birds or other animal 

 or vegetable organisms, also as regards disease among the fish themselves. 



F. Any other causes which may appear to have any bearing on the de- 

 cline in the stock of salmon. 



Finally notice should be taken of any dead salmon incountered, especially 

 after spawning, attention being paid to the number and size of fish. 



Statistics as to average amount of fish taken, amount of spawn and fry 

 laid down, timber rafting, contamination, erection of dams or other obstacles in 

 the way of fish ascending the river, as well as other conditions affecting the stock 

 of salmon for recent years, especially the last decade, are, as far as possible, to 

 be collected and compared. 



