GREAT SKUA 255 
the end of March the ‘ Black ’-headed Gull leaves our shores, 
and although there is no time when a few stragglers may 
not be seen, the great body is absent until the middle of 
June, when they begin to return, still bearing the ‘black’ 
feathers on the head. In summer these birds often behave 
as if still at their nesting grounds; thus on 29th June 1887 
a great flock on the Jurby coast flew over me with agitated 
cries, and on 25th June 1895 the same action was notice- 
able in flocks at the Lhen. The tern-like cries and evolu- 
tions, at all times very characteristic of the species, are 
specially remarkable before a change of weather. 
Comparatively few of our birds are in the variegated 
immature stages of plumage, which do not last so long in 
this species as in the Herring Gull. 
Though in general a very abundant Irish species, this 
Gull does not nest in eastern Leinster, but does so on 
Lough Neagh and some lakes in Down. In Galloway it 
has a number of stations, also in Cumberland, where it 
nests in vast numbers at Ravenglass, just opposite Man; it 
also breeds on Walney, and at a few other localities in 
Lancashire. There is, according to Messrs. Coward and 
Oldham, one large colony in Anglesea. In Shetland it is a 
scarce resident, but much more abundant in Orkney and the 
Outer Hebrides. Its colonies are more numerous in Scot- 
land than in England, though the latter possesses some very 
large ones. 
STERCORARIUS CATARRHACTES (Linn.), 
GREAT SKOUA. 
Mr. Kermode includes this species with the remark ‘ off 
the south of the island in autumn. A specimen was taken 
