LXX REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



resulting- from them appeared strong and healthy until they were about 

 two weeks old, when a large number of them were affected by a disease 

 which had never occurred at the station before. Its first indication 

 was the appearance of a small white spot on the yolk-sac, followed by 

 an unnatural position of the fish in swimming, the body being held 

 perpendicular with the head near the surface of the water. As soon as 

 death resulted the yolk-sac would burst. All the fish affected in this 

 way were liberated as soon as possible. 



About the middle of December a consignment of 3,000,000 salmon eggs 

 was transferred from Battle Creek, California, being shipped by rail to 

 Oregon City and thence to the station by wagon. The eggs arrived in 

 excellent condition, and by January 25 they had finished hatching. All 

 but 500,000 of the fry were liberated, just before the absorption of the 

 sac, in Clear Creek and on the natural spawning-grounds of the salmon 

 in the Clackamas River, within a range of 2 miles up and down stream. 

 Those retained at the station were fed on finely chopped beef liver and 

 on chopped fish when liver could not be obtained. The rate of growth 

 was rapid. On March 10 the total weight of 1,000 of them was 1^ 

 pounds, and on May 31, when the last of them were planted, the weight 

 of the same number was 3 pounds. They were liberated in small lots 

 from time to time during the month of May, and the total loss on the 

 500,000 retained amounted to 11,400. 



The only serious loss in addition to the mortality resulting from the 

 disease referred to above occurred on November 26. There were in 

 the hatchery at that time 000,000 fry in excellent condition when the 

 watchman left the building at 5 p. m. On the arrival of the superin- 

 tendent two hours later all of them were dead. As no one had access 

 to the building and as the water supply was in free operation it was 

 evident that some i^oisonous substance had been introduced into the 

 water before it entered the hatchery, by some ill-disposed person. 



Specimens of the dead fish examined by a chemist in Portland showed 

 the presence of lime and salt. Salt, except in large quantities, is not 

 injurious to fry, but experiments by the superintendent proved that 

 young salmon in flowing water can be killed in a very short time by 

 the introduction of limewater or small pieces of fresh lime. 



During the spring the wagon bridge across Clear Creek was rebuilt, 

 and the mess-house and fences, which had been damaged by high water 

 during the previous winter, were repaired. 



Salmon River Station. 



The site selected for the establishment of the auxiliary station was 

 on a small island in the middle of the Salmon River, about 35 miles 

 from Clackamas Station by wagon road. As the salmon spawn in that 

 river much earlier than in the Clackamas, the rack was put in during 

 the latter j^art of June and arrangements were made with Mr. J. J. 

 Pankey to furnish ripe salmon at 50 cents each. Immediately after 

 the completion of the rack an open shed was erected, the necessary 



