SALMON AND SALMON FISHERIES OF SWIFTSURE BANK 
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throughout which this area has been the heaviest producer of coho salmon. It is 
further evident from these curves that the general level of abundance throughout 
the region has been lower in recent years than at any previous time in the history of 
the fishery. 
That changes in the intensity of the fishery have exerted a considerable influence 
on the abundance of cohos has been indicated. However, abundance has been fur- 
ther affected by changing conditions in the streams where the adult fish spawn and 
the young are reared. Lumbering has been, or is now being carried on in the drainage 
basins of almost every river in the southern part of the region, and most of the cut-over 
lands have been cleared for agricultural purposes. Rapidity of run-offs and resultant 
flood conditions have become increasingly prevalent on these streams, many former 
spawning grounds have been rendered useless, and the carrying capacity of the streams 
for young fish during their stream residence has been reduced. Utilization of streams 
for water power or for industrial purposes has had a similar effect. There is a further 
possibility of the withdrawal of spawning grounds due to the impounding of waters 
in the upper reaches of these rivers for the purpose of controlling floods and erosion. 
It is difficult to determine how far the level of abundance can decline before the 
populations of some areas pass the point at which they are able to rehabilitate them- 
selves, even under the most stringent protection that legislation might offer. In view 
of these conditions it appears highly probable that the decline in numbers of this species 
will be continued unless there is a drastic change in the factors influencing their 
abundance. 
KING SALMON 
By George B. Kelez 
INTRODUCTION 
Populations of king salmon are found in most of the important salmon streams 
in the region, the heaviest runs usually appearing in the larger rivers. Averaging 
more than 20 pounds in weight, the kings are the largest of the 5 species of Pacific 
salmon. Their large size and high quality have always commanded the highest indi- 
vidual price of any of the species, and the greater portion of the catch has been absorbed 
by the fresh-fish markets or used for mild curing. 
Kings from the troll fishery of Cape Flattery appear in the city markets in early 
spring and they are taken in gill nets throughout the fall months, but the bulk of the 
commercial landings are made in late spring and summer. Except in the gill-net 
catches in the rivers, both immature and mature fish appear together in the landings 
during the greater part of the fishing season. Sport fishing for kings, which has been 
popular with residents of the region for nearly 50 years, is carried on from April to 
September. 
LIFE HISTORY 
Possibly because of their greater size and strength, kings usually spawn in deeper, 
faster water than do the other species of salmon. Although the spring runs may ascend 
to small head-water streams, the later runs often spawn in the larger tributaries or 
even in the main channels of the rivers. There is a recognizable difference in the 
