CALIFORNIA FISH AND GAME. 



129 



Numher Killed During 

 Closed Season. 



Bulls 22 



Cows 12 



Calves 4 



Sex not given 80 



Total 118 



Total killed during year 1627 



(Prom Sveriges ofRciella statistick Ut- 

 tlrag- ur revirbersattcheruas uppgifter.) 



In general, the reports show that the 

 moose arc decreasing, due to excessive 



Fig. 59. Rainbow trout caught on San 

 Joaquin River and photographed by A. A. 

 Rohde. 



hunting during the years of crisis. A 

 closed season for several years is con- 

 templated. — G. \V. HuLT, San Francisco, 

 California. 



A PHOTOGRAPH OF A RAINBOW 

 TROUT. 



Since clear, detailed photographs of fish 

 are often difficult to obtain, we are pub- 

 lishing herewith a successful picture of 

 a rainbow trout secured by Mr. A. A. 

 Rohde of Fresno, California, taken near 

 Bass Lake, Madera County, on the San 

 Joaquin River (Fig. 59). Mr. Rohde 

 took this picture with the fish two feet 

 from the camera, using a Ray color filter 

 over the lens and a 5 by 7 plate. The 

 trout weighed 3 pounds and was 8 inches 

 in length. 



DANGER TO FISHERIES FROM OIL 

 AND TAR POLLUTION OF WATERS. 



In the report of the United States 

 Commissioner of Fisheries for 1921, Mr. 

 J. S. Outsell discusses at some length the 

 danger to fisheries from oil and tar pol- 

 lution of waters. He points out that 

 three main sources of oil and tar pollu- 

 tion have been found : Road washings, 

 carrying great quantities of lubricating 

 oil ; gas houses and oil refineries ; tank- 

 ers, oil burners and oil-engined shipping. 

 Tars, tar oils and crude distillery prod- 

 ucts are found generally to be highly poi- 

 sonous, whether in weak or great dilution. 

 Some oils have been found to emulsify to 

 a sufficient degree, with continued agita- 

 tion, to coat the gills of fish and so 

 produce death by suffocation. An oil 

 film, through prevention or checking of 

 aeration, is dangerous, particularly in 

 busy harbors. The deleterious effect on 

 spawning, by rendering spawning grounds 

 unfit or inaccessible, is a grave danger 

 arising from the pollution of harbors and 

 streams. Another serious danger is found 

 to lie in the possible effects on the dimi- 

 nution of the food supply. Through what- 

 ever means, it is an observed fact, ac- 

 cording to Weigelt, that in Germany fish 

 have completely disappeared from pools 

 and ponds following the discharge of min- 

 eral oils into the water. In the sea a 

 great danger is suggested by the fact that 

 the eggs of sea fishes are typically float- 

 ing, and that oil-burning and oil-engined 

 shipping is greatly increasing. 



Remedial measures may (now or in the 

 future) be found: (1) In the recovery of 

 oils from drainage water, as already has 

 been proposed; (2) in the prevention of 

 gas-house and refinery pollution, which 

 prevention should be helped by the in- 

 creased use of "wastes" in by-products; 



