BIRDS OF DUMFRIESSHIRE 431 
Pied Wagtails were tripping about on the frozen river at 
Dumfries amongst some Black-headed Gulls, when suddenly 
a bird of the year made a dart at one of the Wagtails, seized it 
in its bill, and proceeded to batter it to death. The other 
gulls tried to share the morsel unsuccessfully. This attack 
may have been caused by excessive hunger.* 
I have heard the species recently accused of taking the 
eggs of other birds, and there is no doubt that it is almost 
omnivorous ; but at present the balance of good that it does 
to the farmer by its destruction of injurious insects, far out- 
weighs any harm it may do to the sportsman or fisherman. 
Black-headed Gulls are certainly more attached to the land 
than in former years, and they spend nowadays a far longer 
time on the pasture-land than on the shore. 
They often alight on trees and bushes, and Mr. R. Service 
tells me that it was not till the abnormally severe winter of 
1878-1879 that they were seen perching on the houses in 
Dumfries, as they commonly do now. 
The Black-headed Gull breeds in colonies ; the nests, 
made of sedges, rushes, etc., usually contain three, some- 
times two, and still more rarely four eggs. These take 
twenty days to hatch. In some seasons an unknown 
epidemic almost decimates the young ; and in 1900, owing 
it is believed to lack of food from drought, fully 60 per 
cent, of the young birds died of starvation at Loch Urrf 
(Glencairn). 
A nesthng marked No. 3649 on July 12th, 1909, at the 
Dhu Loch (Penpont) was recovered on November 27th of 
the same year at Carluke, Lanarkshire, J that is, thirty-five 
miles north of the spot where it was bred. 
For the excellent photograph, here reproduced, of a colony 
of this species, I am indebted to Mr. D. Legard ; and for the 
following list of local " GuUeries," I must thank many willing 
correspondents. 
* Ann. Scot. Nat. Hist., 1900, p. 120. 
t Trans. D. and O. Nat. Hist. Soc, December 13th, 1901. 
t British Birds (Mag.), Vol. III., p. 251. 
