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THE EFFECT OF THE WINTER OF 1916-1917 
ON OUR RESIDENT BIRDS. 
BY THE 
REV. F. C. R. JOURDAIN, M.A. 
AND 
LIEUT. H. F. WITHERBY, R.N.V.R. 
Parr I. 
THE widespread destruction of Bird-life caused by the 
severe winter of 1916-1917, and more especially by the 
prolonged period of frost which extended late into the spring 
of 1917, was so noticeable that it attracted the attention © 
of the least observant. In most parts of the British Isles 
the diminution of resident species was most marked during © 
the following summer, and in some cases the destruction © 
was so great as to result in local extermination. That the © 
same conditions also affected some of our winter visitors — 
from the Continent has been proved by the extreme scarcity — 
of the Fieldfare (J'urdus pilaris) during the winter of 1917- — 
1918. (Cf. antea, pp. 231 and 261: and p. 280.) As the actual © 
severity of the weather was no greater than that experienced — 
frequently in many parts of the Continent, which does not — 
result in any noticeable destruction of Bird-life, it seems — 
at first sight difficult to account for the difference in the — 
effects, but it must be remembered that many of the species 
which suffered most are at any rate partially migratory, 
and that there are almost always some parts of the British 
Islands where even in the depth of winter, comparatively 
mild and open weather prevails, such as the Devonian 
peninsula and the south of Ireland. In the spring of 1917, 
a great part of Ireland and most of the Cornish coast, which 
for generations have furnished a refuge to frozen-out im- 
migrants, were experiencing the most severe climatic 
conditions of which we have definite records, as may be seen 
from a comparison of the articles by Messrs. C. J. Carroll 
and H. M. Wallis (Cf. antea, p. 26 and X., pp. 267-8) and 
the weakened and already half-starved visitors, were quite 
unable to adventure upon a Channel crossing and perished 
by thousands. 
Probably in almost all cases it was not the actual cold 
which caused the mortality, but the long duration of the 
frost, which held the earth ironbound even to the very edge 
of the sea, and was accompanied by snow, which buried 
