184 THE ESSEX NATURALIST.
through the winter months that ducks are present in large
numbers. At times there must be at least two thousand ducks
over the whole series of reservoirs. The Tufted Duck is
probably the most numerous, and at their maximum the numbers
must run into four figures. Although the Mallard is not such
a numerous species, yet hundreds are present every winter.
The numbers of Pochard vary considerably, but occasionally it
is a very abundant bird, as many as 300 having been counted
in a flock. Teal, Wigeon and Smew complete the list of ducks
which may be described as winter residents. The distribution
of these three species at the reservoirs is not without interest.
The first two confine themselves to the largest of the series,
the King George, while the Smew is rarely seen on any other
reservoir except the Racecourse, No. 4 and No. 5. Before the
construction of the King George, Teal generally found shelter
on the Racecourse. The numbers of Teal which spend the
winter are small when compared with the Mallard and those
of the Wigeon are still smaller. The installation of the Smew
as a winter resident is one of the most outstanding changes for
which the reservoirs are responsible. Prior to 1924 this
beautiful sawbill (the adult male is especially handsome) was
a rare Essex bird. In 1922 a brown-headed bird made its
appearance, but none was seen in the following year ; however,
the species was observed on many occasions in 1924, in which
year it may be said to have established itself as a winter resident.
The Lea Valley Reservoirs are the only locality in Essex where
this species occurs or has occurred regularly. The Smew is
never seen in large numbers, twenty-five being the maximum
recorded, and the adult males are always in the minority.
The Goldeneye, Goosander and Scaup, although they are not
winter residents, probably occur annually, but in small numbers,
six, fourteen and eight being respectively the largest number
recorded. The Shoveler also probably occurs every winter in
small numbers. The remaining" ducks, namely, the Shelduck,
Pintail, Red-crested Pochard, Long-tailed Duck, Common and
Velvet Scoters are all of very rare occurrence. The Shelduck
has been seen in three different years, the Pintail, Common
and Velvet Scoters twice each, and the Red-crested Pochard
and Long-tailed Duck once only. The occurrences of the
Red-crested Pochard, Long-tailed Duck and Velvet Scoter are