146 THE ESSEX NATURALIST.
Little Tern (Sterna a. albifrons Pall,). Hamford Water, 20/4/24
and four or five, 2/8/24. Up the river, 13/7/24, and four, 4/8/24.
Hamford Water is a probable nesting locality.
Great Black-backed Gull (Larus marinus L.). Identified in
all months of visits, usually occasional birds, sometimes no more
than one individual was seen. More were seen in July and
August, when the species was fairly numerous. The months
suggest that migration was the cause of the increase.
Herring Gull (Larus a. argentatus Pontopp.). Identified in
all months of visits except July. At all times very much less
numerous than either the Black-headed or Common Gull.
Lesser Black-backed Gull (Larus fuscus L.). In the river,
13/7/24, immature birds were fairly numerous ; 3-4/8/24 ; there
was a good sprinkling on these dates, immature and otherwise ;
24/8/24, a number, but fewer than the Great. On 21-2/9/24,
there were many both in the river and at Hamford Water. It
will be noted that all these records refer to what may be
described as the migrational period.
Common Gull (Larus c. canus L.). Identified on all visits.
At times the most numerous Gull, some of the gatherings being
of striking size.
Water-Rail (Rallus a. aquaticus L.). One was flushed from a
deep ditch at Wrabness, 19/4/24. The bird flew in front of me
and disappeared in some thick growth. I identified another
bird in very similar manner, near the old decoy at Great Oakley,
21/3/25.
Coot (Fulica a. atra L.). The remarkable numbers of this
species which frequent the river, form an outstanding feature
of the bird-life of the area—one might almost say of the county.
The severity of the weather in the winter 1923/4, accounts for
the specially large numbers which were present during that
season. I first made acquaintance with these congregations on
13/1/24, when I estimated that there were over a thousand Coots
in the flock in front of me and there were many more farther
along the river. Another visit, 10/2/24, confirmed the presence
of equally large numbers, but on 19/4/24 only six birds were seen.
Mr. W. B. Nichols, in a letter to me dated 30/4/24, states "I
estimate the number of Coots at something like 4000."
I renewed my acquaintance with these large flocks in the
winter 1924-5, on 22/11/24 when I estimated that there were