TROUT IX S.A. WATERS 275 



supreme importniue. The Eerste River at Stellenbosch is 

 perliaj)8 the worst example. I have ])icked up 4 or 5 

 dead trout, each about one i>oiind in wei^lit, in one after- 

 noon below Stellenboscii, whilst others were rolling about 

 in a state of semi-asphixiation. In January, the river 

 below the village is very Ioav, and sometimes evil- 

 smelling, as on the occasion above mentioned. The 

 residue of Wineries and Distilleries, together with solid 

 and liquid domestic refuse that had been cast into the 

 town furrows, brought about the unusual mortality. This 

 pollution has, to some extent, been dealt with by the Pro- 

 vincial authorities, and it is to be hoped will not be per- 

 mitted to continue. The washing of brandy and wine 

 casks and the throwing of wine refuse into the river is 

 dangerous to fish life, especially when the river is low, 

 for then the filth finds its way into the more or less 

 sandy pools and is covered by the next flood with sand 

 and other solids. The result is decomposition accom- 

 panied by the production of gas. When wading in these 

 pools in summer, the pressure of one's feet liberates the 

 gas, Avhicli rises in bubbles and is very oftensive; in the 

 same way cattle stir up the decajdng filth, Avhich is 

 carried downstream to injure or kill any young fish or 

 fish food that it may envelope. The mature fish are not so 

 susceptible to the evil influence as the fry and when there 

 is a reasonably copious flow of water in the river they 

 can migrate and evade the nuisance. The extent of 

 damage to the fish naturally depends upon the tempera 

 ture of the water, which at say 40° Fahr. would be com- 

 paratively harmless, while at 80° it Avould be fatal. 



Water Vermin. 



The chief enemies of trout are named in the clause re- 

 lating to spawning, but having watched the havoc 

 wrought by cormorants in the Eerste River, in the Hex at 

 Worcester, and in the lake at the Cape Explosive Works 

 at Somerset West, it seems wise to devote a little space 



