[5] IS SAWDUST INJURIOUS TO THE FISHERIES? 029 



lar saws are constantly coining into more general use, I consider it 

 absolutely necessary to compel the owners of saw-mills by law, no mat- 

 ter whether they use circular or other saws, to collect their sawdust, 

 instead of throwing it into the river. Such a prohibitory law should 

 apply not only to the main stream, but to all its tributaries, aud in fact 

 to all the saw-mills in the district, as there is no doubt that the devel- 

 opment of all the fresh-water fisheries is greatly retarded and injured 

 thereby." 



Under date of September 30, 1879, the governor of the districts of 

 Mandal and List has transmitted to me a number of reports on the 

 sawdust question made to him by the authorities of the various town- 

 ships, from which I shall give a few extracts : 



The authorities of Tveit declare that sawdust has for a long time been 

 considered injurious to the growth and development of the salmon. 



The authorities of Oddernos strongly indorse a report from 2G fishery- 

 owners, in which sawdust and other refuse from the many saw-mills on 

 Torrisdal Itiver is declared to be the principal impediment in the way 

 of the increase of the salmon, as both the young and the farther 

 advanced fish are destroyed by it. 



The authorities of Venuesland declare that all the owners of salmon 

 fisheries are fully convinced that the throwing of sawdust into rivers 

 is highly injurious to the salmon fisheries. 



The authorities of Sogne deciare that, although there are few if any 

 salmon fisheries in their district, it is desirable to keep the sawdust out 

 of the salmon rivers as much as possible. 



The authorities of Holme are unanimous in their opinion that saw- 

 dust injures the fisheries in Mandal River. 



The authorities of Southern Undal declare that sawdust in the rivers 

 is the principal cause of the decline of the fisheries, and that as long as 

 no steps are taken to remedy the abuse of throwing it into the rivers, 

 all protective measures will prove unavailing. 



All the above-mentioned authorities have moreover strongly insisted 

 on the desirability of some law prohibiting the throwing of sawdust 

 into rivers. Similar declarations have been made by the authorities of 

 Northern Undal, Lyngdal, Vanse, Herads, Krinesdal, Nses and Hittero. 



The district authorities to whom these reports were made have, under 

 date of June 27, 1S79, declared unanimously that "they consider it ab- 

 solutely necessary to pass a law, as soon as possible, prohibiting the 

 throwing of sawdust and other injurious matter into salmon rivers and 

 their tributaries". 



The governor also considers it highly desirable to limit, or better still, 

 to prevent entirely, the pollution of the rivers by sawdust or any other 

 impure matter. 



To these declarations I shall add au extract from notes taken by me 

 during a visit made in the summer of 1878 to the salmon streams of the 

 List and Mandal districts : 



