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Obviously the problems caused by Culicoides
to the people of Essex is not a new phen-
omena. Indeed in past centuries with much
larger areas of standing water and marshes the
problems were more intense. In Scotland even
today attacks by Culicoides can make life
very uncomfortable for man and beast at certain
times of the year.
Culicoides are present throughout the world
and overseas they do transmit -filarial worms
which are blood parasites. In Britain,
however, we do not suffer from such problems.
The fourth and last of the major groups of
bloodsuckers is the Simuliidae, known as
blackflies or Buffalo gnats, a reference to
their hump backed appearance.
In Britain their are thirty-five species of
which nearly all the females are bloodsuckers,
though not all of man. In fact these flies
will probably be the least familiar of blood-
suckers to walkers in the Essex countryside.
I have never, that I know of, been bitten by a
Simuliid in Essex though in Scotland they are
avid feeders on human blood. Once in Dorset a
swarm about the size of a large football
followed me around, hovering in front of my
face, repeatedly flying into my face and eyes.
No amount of swatting or running would deter
them. However, none of them registered a
bite: perhaps I did not look appetising enough.
The larvae are aquatic but they require a
higher percentage of oxygen in the water than
the Ceratopogonidae and therefore they only
breed in running water, albeit that sometimes