390 BLACK-HEADED GULLS IN ESSEX.
leading me, with wild screams, like the broken caw of a rook, they
swooped down from their aerial positions, and occasionally I had to
wave my cap and arms to keep them at a respectful distance.
This daring conduct rather reassured me; for the moment I
was somewhat suspicious of that big flock of gulls I had just left,
but in face of the bold behaviour of the black-headed ones, I did
not think that any of the former would have dared to have
approached the colony with egg-stealing intentions. Having
faced the onslaught and disregarded the menacing cries, I attained
the edge of the gulls' nursery.
This was a small, square pond, barely covered with water
and surrounded by high banks. The stunted rushes and flags
growing up from the surface were not thick enough to hide the
nests. As I was wearing sea-boots, I waded out into the middle
of the pond, and came close to the nests, of which there were only
five or six at the most, and only a few of these contained two or
three eggs.
Seeing, too, that there were at most but 20 birds, instead of
the 100 I had expected, who were still wheeling and circling over
my head in the utmost excitement and consternation, my dis-
appointment can be better imagined than described.
The nests are very substantial structures, built of sedge and
rushes, rising island-like from the mud and raised well above the
water.
Just as I was leaving I turned again to have another look,
and then I discovered a young gull standing up quite alone on
one of the larger nests; and turning again a moment after, I found
it had been joined by a second. Doubtless they had been crouch-
ing among the superincumbent rushes, possibly covered over by
the parent birds and hidden in this manner while I was at close
quarters.
With very despondent feelings I wandered off across the rest
of the broad, flat marshes, but though I saw innumerable wild
duck on the fleets and shadows, I could make out no more black-
headed gulls.
I hasten, however, to reassure my readers. We need not
jump at once to the conclusion that the birds are deserting their
breeding grounds. My visit was undertaken somewhat late in
the season (July), although that cannot account for the paucity
of birds; but it seems to be the consensus of expert opinion that
the cause for the great decrease in the number of the gulls is