PROGRESS IN BIOLOGICAL INQUIRIES, 1938 39 
quently expected to extend over several years, permitting 
determination of growth and longevity of he eee Seite is 
The results obtained from the 1937 and 1938 tagging experiments 
show that: (1) There is a slight amount of straying from one water- 
shed to another but on the whole the chars return in the fall to the 
same streams from which they entered the ocean. (2) Many, if not 
all, of the chars that migrate seaward in the spring, return to fresh 
water in the fall of the same year and migrate seaward again in the 
spring of the following year. (3) There are at least two populations 
of chars in the Karluk watershed, those that live in Karluk Lake and 
those that live in the river. However, these populations mix to some 
extent. (4) The chars in Karluk Lake do not comprise a homo- 
geneous population but are apparently divided into several rather 
distinct groups which intermingle to a slight degree. (5) The chars 
im this watershed have a relatively slow growth and are relatively 
long lived. (6) Sea-run chars make a faster growth during the time 
they are in the ocean than do the non-sea-run type during the same 
period of time. (7) Sea-run chars, on the average, make no growth 
i the 8- to 9-month period spent in fresh water between the upstream 
migration of one year and the downstream migration of the following 
year. Length-weight measurements made in the spring, and again 
in the fall, have shown that there is a marked difference in the con- 
dition factor of the downstream and upstream migrating chars. 
During the few months spent in the ocean these fish increase in 
weight from 60 to 100 percent, and about two-thirds of this weight 
increase is lost between the time of the upstream migration of one 
fall and the time of the downstream migration of the following 
spring. This loss in weight is attributable to the fact that these 
fish spawn during the period spent in fresh water and also in part 
to the limited food supply available during the winter months. 
A cooperative observer’s meteorological station was installed at 
Karluk in the latter part of June 1937. Data for the first fiscal year 
were complete by June 30, 1938. The collection of these data is of 
considerable importance in view of the marked effect climatic condi- 
tions have on the survival of salmon. The average monthly rainfall 
was 2.77 inches, the total for the fiscal year being 33.26 inches. There 
were 110 clear days and 255 cloudy or partly cloudy days. There 
was precipitation on 149 days. The highest air temperature during 
the year was 66° F. and the lowest was 6° F. The yearly mean 
average was 40.3° F. 
PINK SALMON 
The pink-salmon investigation during 1938 dealt with the factors 
contributing to the change in abundance and the time of appearance 
of the pink-salmon runs in Southeastern Alaska. This investigation 
was carried on by Dr. F. A. Davidson and Samuel J. Hutchinson. 
The work was confined to a study of the pink-salmon runs in South- 
eastern Alaska which comprise the bulk of the Alaska pink-salmon 
catches. The total 1938 catch fell below previous yearly packs and, 
according to all indications, the runs are maintaining themselves with 
difficulty under the intensive commercial fishery. If the condition of 
the runs is not improved in the very near future, drastic measures 
will have to be taken to rehabilitate these salmon populations or they 
will soon fall to a dangerously low level of abundance. 
