44
THE THREATENED DESTRUCTION OF
into immediate contact with the spawning grounds of the English
native oyster, and in the centre of an unique and priceless industry
which has been carried on from time immemorial. The sea-water in
these parts being shallow, and broken into numerous channels by
sandbanks, the sewage would be held in check, and drift at certain
sets of the tides and currents into the rivers Crouch, Roach, Colne,
and Blackwater, the estuaries of which are all immediately contiguous
to the site selected for pollution. From a national point of view, no
more unfortunate selection could have been made, and it is to be as-
sumed that those responsible for the plan cannot be aware of the
importance and magnitude of the interests involved in oyster culture
in this district. To the rivers mentioned, the native oyster is almost
alone indigenous, and it is here that the spat or brood is most success-
fully caught and preserved. Whether this success is owing to the
peculiar character of the water, the natural disposition and formation
of the river-beds and oose, the admixture of the exact necessary pro-
portions of salt and fresh water, or the sheltered position and equable
temperature at that most critical time, the spawning or spatting
season, no one has yet been able to explain satisfactorily, and Nature
still holds the secret.
The chief occupation of the oyster cultivator consists in preparing
and clearing his grounds for the reception of the spawn or spat, and
in continuous daily toil in protecting the young brood from its
numerous enemies both in the water and "on the earth beneath."
That inexorable law of nature—the survival of the fittest—holds as
strongly in this division of animal life as in all others.
" Large fish have little fish
Which on their backs do bite 'em,
The little fish still smaller fish
And so 'ad infinitum' "
From its earliest and most helpless stage of existence to that of
robust maturity, the oyster is relentlessly pursued by all sorts and
conditions of organisms inhabiting its own element.
It is estimated, and from my own experience as a microscopist I
do not hesitate to confirm the assertion, that every oyster with spawn
yields not less than a quarter of a million of its own species. The
first few hours or days of its separate existence,—fifty of them can at
this stage be picked up upon the point of a needle—are naturally the
most critical. It is then in a most sensitive and defenceless condi-
tion, and although fully equipped at the time of emission with