66 
BULLETIN OF THE BUREAU OF FISHERIES 
This is apparent from the distributions of the returns shown in Tables 36, 37, and 
38. In most of the early distributions the frequencies gradually rise to a fairly 
well-defined maximum and then fall — a good indication that the distributions are 
approximately complete. If these distributions are then complete, we may fairly 
compare the median time required for the journey to Bristol Bay with the time 
required for 2 per cent of those tagged to reach Bristol Bay, and from this com- 
parison can arrive at some conclusion as to the relative values of these two measures 
of the time required. From the data given in columns three and four of Table 39 it 
is very apparent that the values of these two measures are so nearly identical that 
for all practical purposes they may be so considered. The average difference of 
the times given in these two columns is exactly one day, the median time being 
the longer. It is furthermore apparent that even in the case of the later experi- 
15 20 25 30 5 10 15 20 25 
JUNE JULY 
DATE OF TAGGING 
Fig. 11. — Showing time required for red salmon to travel from Morzhovoi Bay to Bristol Bay 
ments the median is a satisfactory measure of the average time required to make 
the journey. The rates of travel shown in the last column of the table are there- 
fore based on the median. 
The increase in the rate of travel during the course of the season is very apparent 
from the figures given in the last column of Table 39. With but one exception 
the rate for each tagging is higher than for the preceding experiment. Early in the 
season the rate is approximately 20 miles per day, and toward the end of the season 
it rises to nearly 30 miles per day. Inspection of the table shows that for experi- 
ments begun on approximately the same dates the rate of travel is nearly the same 
in the case of Ikatan and Morzhovoi Bays, but that the rate is several miles a day 
faster in the case of the experiments begun in the region of Unga Island. This is, 
of course, in complete accord with the fact frequently noted before that the fish 
farthest from their spawning grounds travel at the fastest rates. 
It has been of interest to compare the results obtained in these experiments 
with those of 1922. From the tables given in the report on the marking of 1922 by 
