BLACK-HEADED GULLS IN ESSEX. 391
entirely owing to the absence of their accustomed food, caused by
the devastating tidal overflow last winter. Doubtless when the
insect food, on which the birds depend, re-appears, the gulls will
also return in their accustomed numbers.
It seems that during the breeding season these birds subsist
on, or perhaps their young demand, a diet of insect life and grubs
from the dank, moist fresh-water marshes, and these the inrush of
salt-water had unfortunately destroyed.
Mr. Miller Christy kindly wrote and gave the same reasons
as his opinion.
Dr. Salter, who owns the marshes, wrote in the like strain,
regretting to hear of the diminution in the number of the gulls,
and said further that quantities of Pochards which usually bred
there had deserted this year, he supposed from the same cause.
Mr. Champion Russell, of "Stubbers," near Romford, also
courteously informed me that the same thing had occurred in the
large gullery at St. Osyth, where there were only five or six nests
this summer.2
These are the only two Gulleries I know of in Essex; but
considering the nature of the vast stretches of swamps and salt-
ings in the Hamford Waters, perhaps, through the medium of the
Essex Naturalist, I may be informed that there is happily
another colony there.
One word in conclusion. These colonies of Black-headed
Gulls are among the most valuable possessions of bird life we
treasure in the county of Essex. Amongst others, for the follow-
ing reasons:—
1. The beauty of the bird is well known, especially in the
breeding season when it assumes its little black hood, its orange-
red beak and scarlet legs.
2. The breeding places of this bird are very rare indeed in the
South of England; they are daily becoming rarer, and those in
Essex are the nearest to the Metropolis.
3. They are survivals of colonies that have existed in the
county for centuries, and the only seabirds that breed there in
any large numbers.
4. Their curious habit of nesting in company render them
particularly interesting and instructive to the patient investigator.
2 See note on this breeding-place by Mr. Fitch in Essex Naturalist, vol. iii,, 188.
When he visited it, in June, 1889, he counted between 30 und 40 nests.—Ed.