288 MR. 0. V. APLIN ON THE DISTRIBUTION IN GREAT BRITAIN 
local bird. It is commonest in parts of Southern, South-eastern, 
and Eastern England, of the home counties, and of North Wales. 
To Scotland this Shrike is merely an occasional visitor. The 
evidence of its breeding in that country is, I believe, hardly 
satisfactory, resting, according to the data at my disposal, upon the 
observation of adult birds in the early, and of young birds in the 
latter part of summer. As the Red-backed Shrike is a late spring 
migrant, and changes its quarters almost immediately after its 
young become strong on the wing,* this evidence is not conclusive. 
In Ireland it has only occurred on one occasion, so far as I have 
been able to ascertain. 
So locally, however, is this bird distributed in the breeding 
season, that it is impossible to get a right notion of its British 
range without reading the evidence which has been adduced, in 
extenso; I have accordingly laid the whole of it before the members 
of this Society. 
The distribution of the Red-backed Shrike seems, within certain 
limits of latitude and longitude, to be determined mainly by the 
nature of the soil and climate, and the bearing of these upon the 
insect life of a particular district. The favourite food of this 
Shrike during its residence with us consists of large-bodied insects 
especially beetles and bees ; and I believe that the comparative 
abundance or scarcity of that food in any given district largely 
determines the numerical strength or weakness of this species 
therein. So far as I can learn, Mudie is the only author who has 
hitherto paid much attention to this point. He Avrites (‘ Feathered 
Tribes of the British Islands,’ 2nd ed., vol. i. p. 23G), . . . . “it 
leaves the gravelly and clayey districts, and takes up its abode in 
a central zone, beginning at the channel, and terminating at the 
light soils in the valley of the Dee. The climate of that zone is 
warm, and the soil peculiarly adapted to the habits of the larger 
beetles, which seem the natural and peculiar food of these birds ; ” 
and it must be confessed that there is a good deal in what he says, 
although I cannot entirely agree with his definition of the exact 
range of the bird, and the kinds of soil it affects or avoids. 
* Mr. J. Lucas writes : “ These birds commence their autumnal migration in 
July, when they are to be seen along the coast of Sussex. On July 30th 
and 31st, 1867, I saw two at Heene; and on August 7th and 8th, S. F. Lucas 
shot two migrating” (‘Zoologist,’ 1870, p. lot). 
