266 THE ESSEX NATURALIST.
residents commence to move in the direction of their winter
quarters. The autumn passage and the departure of the
summer birds are completed about the middle of October. The
appearance of the winter-residents synchronises with the
departure of the summer birds and this influx is not completed
until some months later. Beyond the fact that the birds of
the different categories which have been mentioned appear
and disappear we know very little. It has been shown, however,
that most of our summer-residents arrive on the south coast of
England and proceed overland to Essex, but a few may arrive
directly on our coast. The movements which have been
outlined deal with what occurs in the county, and I now wish
to discuss migrations which have been witnessed on the sea and
which may have some influence on the bird life of Essex.
There are situated at various distances from the Essex coast
eight light-stations, the most important of which from our point
of view are, firstly, the Kentish Knock L.V. and, in lesser degree,
the Galloper L.V. As the result of two investigations based on
observations made on these light-stations and carried on in each
case over a period of years, migrations of a remarkable nature
were revealed. These flights follow various routes, but chiefly
they were between north and south and east and west. It is
doubtful if, owing to the position of Essex, the first has much
influence on its bird life. During the course of the two enquiries
about seventy species or subspecies were observed on migration
at the eight stations. This number included seventeen species
which are to be seen in Essex throughout the year. The flights
of birds, which have been witnessed at the light-stations, are
of a very impressive nature. They have been mainly observed
from about the middle of September, the greatest activity having
been noticed in October. May and June are the only months
in which migration has not been observed. The chief participants
in these flights are Skylarks and Starlings, and in smaller numbers
Chaffinches and Sparrows. The migrations at times are of
great magnitude, when thousands of birds have been seen, and
so striking have been these assemblages that they have been
likened to a shower of snow. Sometimes hundreds have perished
by striking the rigging of the vessels. Although the numbers
have not been maintained at such heights yet they have been