782 
BULLETIN OF THE BUREAU OF FISHERIES 
GROWTH 
The time of hatching of the eggs depends on temperature conditions, but usually 
occurs during the early spring. The greater part of the young fish remain in the 
streams throughout the summer and the following winter, and usually migrate to 
salt water early in their second year. 
Growth in fresh water is quite rapid, especially in the streams of southern Puget 
Sound where temperatures are favorable and food is plentiful. In these streams the 
fry usually have attained a length of approximately 30 mm by early March, whereas 
those in the more northerly part of the region may not reach this size until the latter 
part of May. By September the size range of the southern fingerlings is from 60-70 
mm. Collections of fish in their second year, taken in early March, show a size 
range of from 80-95 mm. By early May these fingerlings measure from 100-130 mm. 
During spring and early summer the fingerlings migrate from the upper reaches 
of the rivers to the estuaries, and finally into salt water. Scale collections from 
these populations indicate that the majority of the fingerlings migrate to salt water 
during the early spring freshets, but that many remain in the streams for a much 
longer period of time. 
After reaching the inner waters of the region, young cohoes may be found in large 
schools for a period of several weeks. At this time they have reached a size of from 
14-20 cm. The greater part of these young fish gradually migrate to the waters of 
the Pacific Ocean. Clemens (1935) states that tagging experiments have indicated 
that some of the cohoes never leave the Strait of Georgia. Sport-fishing catches in 
the lower sound confirm the presence of cohoes there throughout all stages of their 
life in salt water. 
These fish remain in salt water during the second winter of their life, and through- 
out the following summer, during which time they experience a remarkable increase 
in size. Gilbert (1913) reported the cohoes at the cape to average 13.35 fish per case 
on July 23 and 7.56 fish per case on September 2. Smith (1921) stated that the 
average weight of cohoes taken by troll ers in the same region increased from 5.63 
pounds on July 8 to 9.75 pounds on September 2. Recent samples from the com- 
mercial catches taken in the inside waters of Puget Sound during October indicate 
a size range from 5.13-14.90 pounds, and an average weight of 9.47 pounds at this 
time. Individual fish of more than 20 pounds in weight have been taken by sport 
fishermen in this region. 
Some indications of the migrations of cohoes in inside waters are given by tag- 
ging experiments reviewed by Clemens (1930). Recoveries were made of forty- 
seven immature cohoes tagged in 1927 at Deep Bay, in the northern part of the Gulf 
of Georgia. Of these, 29 were recovered north of the point of tagging, or on the 
lower coast of Vancouver Island, 3 were recovered in the Fraser River, and 1 in the 
nearby Capilano River. Approximately 30 percent were recovered in Puget Sound, 
some being taken as far south as Whidbey Island. 
From a similar experiment at Nanaimo in 1928, 163 recoveries were made. Of 
these, 34 were taken north of Nanaimo and 34 in the general vicinity of the tagging, 
43 were taken in the Fraser River and vicinity, 8 were taken in the Strait of Juan de 
Fuca, or west of it, while 44, approximately 27 percent, were taken in Puget Sound. 
