REPORT OF COMMISSIONER OF FISH AND FISHERIES. 97 



men in a boat, the plan being to attach one end to the shore and pay 

 it out quietly in the are of a circle around a spawning-bed. 'I'he in- 

 closed salmon are then driven into the net by movements of the boat 

 and splashing of the oars. The spawners are put into pens provided 

 near the spawning-shed, which stands upon a large float in front of 

 the hatchery, and the same process is repeated upon another part of 

 the shore. As night approaches the nets may often be left set for two 

 hours or more. On the same day or the one following the fish are 

 handled in the usual manner by the spawn-takers. 



The season practically closed October 28, though a few eggs were 

 taken as late as November 10, and resulted in the collection of 

 11,613,000 eggs from 3,218 females. No record was kept of the num- 

 ber of males, but it is believed that at least 5,000 were used. 



The hatchery, which is a wooden structure, is fitted with 74 troughs, 

 each 16 feet long and containing 7 baskets. The number of eggs 

 placed to a basket varied from 30,000 to 40,000, and each trough was 

 given a maximum flow of 12 gallons of water per minute. The period 

 of incubation for the first eggs collected was seventy-two days, at a 

 mean temperature of 45° F., corresponding closely to the rule of fifty 

 days at 50°, and five days more or less for each degree of lower or 

 higher temperature, as established by Seth Green. The hatchery is 

 supplied with water from the creek, which drains the hills on the 

 south side of the lake, its normal volume being about 200 miner's 

 inches of water, equal to about 2,000 gallons per minute. It is unfor- 

 tunately subject to sudden rises, and at such times is muddy, which 

 will necessitate the erection of a settling tank at some time in the 

 future, in order to guard against losses of eggs. 



Of the eggs collected, 92 per cent hatched, and 10,683,000 fry were lib- 

 erated in the lake and in Skagit River. No attempt was made to ship 

 eggs from the station on account of its isolated position. Hamilton, 

 the nearest railroad station, is 36 miles away, and 18 miles of this dis- 

 tance is over a mountain trail. It is hoped that during the next year 

 a trail will be opened up on the south side to Baker, where the rail- 

 road is now extending its tracks. 



•A few silver salmon appeared in the lake after the bluebacks, but 

 as the hatchery was crowded, no attempt was made to handle them. 



An effort was made to collect steelheads when the first fish appeared 

 at the foot of the lake on March 0, but between that time and May 

 8 only 81 were captured in the gill nets. These were placed in the 

 floating-pens to ripen, but most of them died, the 14 surviving females 

 yielding 52,000 eggs, which hatched in about seventy-five days, in a 

 mean temperature of 40^°. The losses aggregated 50 per cent, and 

 occurred largely in the early stages of development. The mortality 

 was supposed to have been due to the parent fish failing to properly 

 mature their eggs on account of confinement in the pens. 



F. C, 1900—7 



