BIRD-ASSOCIATIONS IN SCOTLAND II 
BIRD SASS © CEATIONS IiNes COmeAN DD: 
By the late Captain SYDNEY E. Brock, M.C.! 
THERE is, I suppose, no country in the world with a more 
voluminous bird literature than this, and it might not 
unreasonably be supposed that at least little remains to 
be said on the distributional aspect of the subject. How 
far that is to be considered so, depends upon the point of 
view. The value of an account of a local fauna, as I 
understand it, depends upon the completeness with which it 
gives us the “what,” the “how” and the “why ” of its faunal 
distributions—a threefold enquiry answered by the cor- 
responding progressive steps of a complete biological 
survey: the faunal list, the correlation of distribution with 
the natural features of the area, and lastly, the collation 
and measurement of the bionomic factors affecting the 
fauna. So far as birds are concerned, the first of these, 
the faunistic, is covered by the local bird list; the second, 
or ecological, is ostensibly so; the final stage of enquiry, 
theMmiMometnic. is mcontessedly snot dealt hwithy) lt) 1s the 
second stage, the “how” of the distribution of birds—the 
ecological aspect—that I wish to touch on mainly here. 
The local list, as we get it in this country, claims to place 
on record the species found within defined limits, and to 
give an account of their comparative abundance and manner 
of distribution; and the customary method followed is to 
give in the first place a general sketch of the area dealt 
with, and to follow this up with a list under heading of 
1/This paper formed part of a bundle of MSS. found among the 
effects of the late Captain S. E. Brock, and handed to me by his brother, 
Dr A. J. Brock, a few months ago. It is understood to have been written 
in 1913 or 1914, and though perhaps not exactly as the author would 
finally have published it, there are no indications that material altera- 
tions were contemplated. It is a fresh and interesting attempt to deal 
with the bird-life of Scotland on an ecological basis, and should be 
read along with the author’s paper on “The Ecological Relations of 
Bird Distribution,” published in 1914 (British Birds, vol. viil., pp. 
30-44).—W. E., 29¢2 November 1920.] 
