OBSERVATIONS UPON FISHES AND FISH-CULTURE. 
53 
not to put in tlie rack at the Clackamas in future until the first run has ascended to 
their natural spawning grounds. 
Early in September, 1888, owing to some peculiarity of the water supply of the 
Clackamas hatchery, serious injury to the eggs and young fish was observed. Investi- 
gation showed that at the time the early eggs were placed in the hatchery Clear Creek 
was very low, little rain having fallen and the impurities and minute vegetable and 
animal growth, which had accumulated in the creek during the summer from natural 
causes and from the deposits of mills up stream, remained in it. It was believed also 
that the great variation between the temperature of the Clear Creek water during the 
twenty-four hours, a difference of 10° having been noted, was another important factor 
in the imperfect development and death of eggs and embryos. 
Mr. Stone believed further that many of the eggs taken early in the season were 
spoiled inside of the fish before they were taken. He thinks that a large percentage 
of the breeding salmon that were spawned before and perhaps during the first week 
in September contained these worthless eggs. 
The egg-collecting season on the Clackamas Eiver, Oregon, extended from August 
28 to November 6 in 1889. The largest number of eggs taken in one day was 208,000, 
on September 27 ; the least number was 4,000, on August 29 ; the daily average of eggs 
collected was 62,514. The females handled numbered 957 ; the average number of 
eggs to each was 4,507. Mr. Hubbard states that more males are taken always than 
females. He estimated that the fry produced in the hatchery equaled about 85 per 
cent of the number of eggs introduced into the building. 
Mode of capture . — Four traps were built in Clackamas Eiver for catching salmon, 
one on the rack and three below it on the shallow riffles. These traps were placed at 
the lower end of a riffle where the water is very swift and the bed of the river has a 
good deal of fall. They are built of poles or slats in such a way that the water runs 
into the mouth of the trap with a great deal of force and passes out through the bottom, 
leaving the fish that come into them on the floor. Wings extend from the mouth 
of the trap up the river, diverging until at the upper end they are as far apart 
and take in as much of the river as possible. The fish are driven into these traps by 
stretching a net across the river some distance above the trap and drawing it down 
stream, driving the fish before it into the trap. The ripe fish are then taken out and put 
into pens when ready for spawning, the unripe ones being returned to the river. 
Atlantic Salmon ( Salmo salar). 
In 1888 a plant of 20,000 fry, from Cold Spring Harbor, N. Y., was made in the 
Nissequogue Eiver, Long Island, and this was repeated in 1889. The growth of salmon 
in this stream is remarkable; a yearling, caught by Mr. L. D. Huntington, May 15, 
1889, was 7£ inches long and 1£ inches in greatest depth. In 1889 the station received 
from the hatchery at Orland, Me., 700,000 eggs; of these 25,000 were sent to the Fulton 
Chain hatchery, New York, and 17,500 to the hatchery of the Bisby Club, in Herkimer 
County, N. Y. These waters empty into Lake Ontario at Sacketts Harbor. The 
remaining eggs furnished 20,000 fry for the Nissequogue, as above stated, and 618,188 
for tributaries of the Hudson. 
On September 19, 1888, Mr. Atkins found, at Craigs Brook, a parr 6£ inches long 
which gave milt. 
The rearing operations at Craigs Brook, Me., during the summer of 1889 were 
