no 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Table of seine-haul and water-temperature records. 
Place. 
Date. 
53° 
54° 
55° 
56° 
57° 
58° 
59° 
60° 
61° 
62° 
63° 
64° 
65° 
66° 
67° 
68° 
July 8 
May 17 
July 0 
May 17 
July 9 
Aus. IS 
6 
14 
Do 
55 
River at Sims 
50 
Do 
177 
Do 
148 
Do 
Sept. 18 
Oct. IS 
178 
Do 
81 
May 4 
May 18 
July 11 
Aug. 13 
Apr. 30 
July 13 
Apr. 28 
July 14 to 31 
May 22 
May 22 
May 23 
May 27 
May 11 
May 13 
June 17 
50 
Do.l 
66 
Do._. 
8 
Do 
0 
60 
60 
Do... 
2 
Redblulf 
150 
Below Redblulf 
0 
0 
0 
Mouth of Thomas 
4 
25 
8 
■ 28 
6 
Rio Vista _ 
2 
2 
1 
Conclusion drawn from study of summer residents.. — It seems evident from 
these observations that the later fry that hatch in the headwaters, or are planted 
there after the spring freshets have passed, are liable to remain till the rains of the 
following winter. This means a slow growth for at least 6 months, or about a fifth 
of their growing period. It means the precocious maturing of the males, which may 
be responsible for the great number of dwarfs known as grilse; and it means that 
15 per cent will become infested with gastric parasites. For these reasons it is 
imperative that the fry from our hatcheries should not be released above Redding- 
after the spring freshets, though they may be released in the headwaters earlier 
without any detriment, and they certainly should not be held after this time merely 
for the purpose of feeding. Superintendent Shebley of Sisson Hatchery states, as 
this paper is going to press, that there are not nearly so many young salmon 
remaining in the Sacramento River near Sisson during the summer since he has 
quit holding the fry in the hatchery during the spring for feeding as there were 
when he did so hold them. There is no advantage in holding fry in the hatcheries 
for feeding. 
FOOD OF YOUNG SALMON. 
General study of food in fresh water.- — The young salmon feed principally upon 
floating or drifting insects, either immature or adults. When feeding they often 
take a station below a stick or rock and catch their food as it floats down on either 
side. They eagerly catch small insects and larvae if thrown into the water. Fry 1.5 
inches long have been observed to rise to a small fly that alighted on the water. They 
hardly ever eat encased caddis larvae, although that is the main food of the trout. 
The following is a tabular statement of the stomach contents of 225 young 
salmon, being based on an examination of about five specimens from each locality 
each month in the year in which any were taken. The record for each fish examined 
consists of the station, date, size of fish, and number of specimens of each kind of 
food or other material found in the stomach. Four forms of insects are recognized 
in the table, viz, larval; pupae, including nymphs; flying insects; and “terrestrial 
insects,” including adult wingless insects and spiders. 
