BULLETIN OF THE UNITED STATES FISH COMMISSION. 
202 
assumption by the United States of - the control of the fisheries of international waters, 
as is already the case with navigation, would permit the conclusion of a treaty with 
Great Britain by which alone could adequate protection be assured. 
Having arranged the foregoing preliminaries, the important work of artificially 
propagating salmon could be undertaken with every prospect of success. The Maine 
hatching stations of the U. S. Fish Commission could furnish an abundance of salmon 
ova for the first few years, after which the supply could be drawn from Lake Ontario, in 
the opinion of United States Fish Commissioner McDonald. He also thinks that gen- 
erous plants of yearling fish in the head waters of the rivers formerly frequented by 
the salmon will accomplish more than the simple deposit of fry in these waters or in 
the lake. The employment of the young of the land-locked variety of salmon would be 
an important feature of the work of rejuvenating this fishery, for it is probable that 
the instinct to migrate to salt water would in this fish be lost and the constant pres- 
ence of salmon in the lake basin would be secured. To sum up this subject in the 
words of Commissioner McDonald : 
The regeneration of the fisheries must he accomplished through fish-cultural work, systematically 
and persistently pursued. Their maintenance must he assured hy the concurrent regulation of the 
lake fisheries hy the United States and Canada and by the enforcement on the part of the State of 
New York of such regulations and requirements 'as will permit the salmon to ascend to their spawning- 
grounds. In the absence of such regulations and requirements it will not he reasonable to expect that the 
results of fish-cultural work will be permanent or compensating, however extensive such work may be. 
A fish-cultural station planned to meet all the requirements must be very extensive and complete in 
all its appointments. * * * The hatchery must be commodious, providing * * * for the incu- 
bation of 1,000,000 salmon ova. It must also provide trough accommodations for holding 1,000,000 
salmon fry for some weeks after they begin feeding. * * * An extensive system of ponds for rearing 
the salmon must be constructed, for none would be released in open waters until they were of sufficient 
size to have comparative immunity from capture by other fish. * * * The station should be 
~ placed * 11 * convenient to transportation routes, and should control a gravity water 
supply which should be without stint or measure. 
THE LAKE TROUT OR SALMON TROUT. 
Next to tbe wbitefish, the lake trout ( Salvelinus namaycush) is probably the most 
highly esteemed species occurring in Lake Ontario, a popularity arising from its com- 
mercial importance, food value, game qualities, size, and beauty. Regarding the size 
of the Lake Ontario trout, it may be said that examples weighing 24 pounds are some- 
times taken, but the average weight is much less than that. The fish caught in seines, 
on lines, etc., do not average more than 2 pounds, but in the large-meshed gill nets, set 
especially for trout, the average is probably 8 pounds. 
Trout are now very scarce on the American shores of Lake Ontario, and the 
decrease in the catch since 1880 has been one of the most remarkable changes in the 
fisheries of that body of water. In 1880 over half a million pounds were taken ; in 1890, 
although the yield was double that in 1885, only one-fourteenth of the catch in 1880 
was obtained. The figures for the three years mentioned are as follows: 
1880 
1885 
1890 
Pounds. 
569, 700 
20, 510 
41. 010 
