THE PROTECTION OF MIGRATORY BIRDS 
IN CANADA 
AN ACCOUNT OF THE INTERNATIONAL TREATY OF 1916 BETWEEN 
GREAT BRITAIN AND THE UNITED STATES FOR THE 
PROTECTION OF MIGRATORY BIRDS IN THE 
UNITED STATES AND CANADA 
BY C. GORDON HEWITT, D.SC., DOMINION ENTOMOLOGIST 
F OR many years the numbers of 
our migratory birds such as 
ducks, geese, insectivorous 
birds and shorebirds, which class 
includes the plovers, sandpipers, 
snipe, woodcock, etc., have been 
decreasing. This decrease is a mat¬ 
ter of common knowledge and obser¬ 
vation throughout the Dominion. 
Certain of these migratory birds, 
such as the Eskimo plover, which 
formerly existed in enormous num¬ 
bers and was killed for the market, 
the Labrador duck, the passenger 
pigeon and the great auk have now 
become extinct. Others such as the 
whooping crane and the wood 
duck, the most beautiful of our 
native ducks, have become so re¬ 
duced in numbers as to render their 
continued existence without further 
protection a matter of doubt. 
From a national standpoint the 
prospect of this continued decrease 
involved serious economic considera¬ 
tions. Leaving out of account the 
value from an aesthetic point of view 
of this portion of our Canadian wild 
life, great as that is, and regarding it 
as an economic asset to the country, 
we were faced with the gradual 
reduction of our migratory wild¬ 
fowl, whose value as food and as 
means of securing recreation is 
inestimable, and of our insectivorous 
birds, which are of even greater 
importance to the welfare of our 
agricultural interests. 
Insectivorous birds constitute one 
of the chief natural agencies con¬ 
trolling insect pests affecting field 
crops, orchards and forests. In field 
crops alone the annual loss in Canada 
due to the depredations of insect 
pests is, on a conservative estimate, 
not less than $125,000,000. And, 
with the development of the country, 
the damage caused by insect pests 
is increasing, while the numbers of 
insectivorous birds have been de¬ 
creasing. 
The chief causes of this decrease 
in the numbers of our migratory 
birds are as follows: Canada con¬ 
stitutes the chief breeding place for 
the greater number of these birds. 
With the settlement of the country 
the breeding places of many species 
have been destroyed. The clearing 
of the land has involved the clearing 
of the nesting sites of insectivorous 
birds; the draining of marshy areas 
and the settlement of the prairies 
have driven wild-fowl from their 
former breeding and feeding places. 
Such causes are, therefore, una¬ 
voidable to a large extent. On the 
other hand, while many of the prov¬ 
inces have excellent laws governing 
the protection of game, non-game and 
insectivorous birds, it has not always 
been possible to give these birds 
adequate protection. The increase 
in the number of persons who carry 
guns and the improvement of modern 
sporting guns have had their effect 
on the abundance of wild-fowl. 
Even with the strictest enforcement 
of protective laws Canadians would 
have been unable to prevent the 
continued decrease of migratory 
birds unless the requisite protection 
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