296 - BRITISH BIRDS. 
charge at dusk to seek a scanty meal for a few minutes, and to relieve 
her cramped and weary limbs ; but Naumann says that she is by no means 
a close sitter, and often leaves her eggs in search of food during the day. 
The Swift only rears one brood in the year; there is no time for a second, 
for the young birds are seldom hatched before the middle of June. Should 
the first eggs be taken, a second clutch is sometimes laid; but these are 
frequently so late in coming to maturity that the young are abandoned 
and left to starve in the nests by the old birds, whose impulse to migrate 
is stronger than their parental love. The young birds remain in the nest 
for a considerable time, longer than those of the Swallow and the 
Martin, and are not tended much by their parents when once they are 
able to take wing, though Dixon has seen them being fed by the old birds 
in the air. The Swifts do not visit the nest so frequently as Swallows 
do; they have fewer young to cater for, and probably amass a larger 
number of insects in their mouths ere they return. 
The food of the Swift is composed entirely of insects, all of which it 
catches in the air; they are usually of the smallest kind, such as gnats, 
midges, small beetles, &. Gilbert White states that they also feed on 
may-flies and dragon-flies. The indigestible portions of the food, such as 
wing-cases &c., are cast up in pellets, and the nests often contain a great 
many of them. The young birds are much troubled with parasites, and 
the nests often swarm with them, but are seldom deserted from this cause. 
The Swift quits this country early in the year; and is often seen 
passing in great flocks along the east coast of England im the autumn. 
Gray mentions that this bird congregates in enormous flocks in Scotland 
in August ; but it is possible some of these birds are merely passing along 
our coasts from the continent on their way southwards, and are not 
indigenous to this country. They are seen at the various lighthouses 
on our east coasts, not only on migration, but also during the summer ; 
and at Spurn lighthouse a flock has been known to remain on the 
gallery of the lantern at night. Like the Swallows, the Swifts are 
specially noisy before they finally leave. They depart en masse in the 
night; and on the day following their departure their usual haunts 
seem quite lonely after their sudden and complete disappearance. 
The Swift in summer has the general colour of the plumage uniform 
blackish brown, with a bronze tinge on the upper parts. The throat is 
dull white; bill black; feet and claws very dark brown; irides dark 
brown. The female does not differ in colour from the male. Young in 
first plumage have the chin a purer white, because the feathers are newer, 
and most of the feathers of the upper parts are narrowly margined with 
buffish white. The colour of the plumage after each moult is dark and 
rich, but the “bloom ” is soon bleached away by the action of the sun and 
weather. 
