|Abstract||The native oyster season of 1921 opened with a black disaster. Almost every fish in the drudges was dead when
they were hauled. It all but spelt the end of an industry, a cult, a way of life, which stretched back unbroken and almost unchanged to Roman times.
Professor J.H. Orton, a Doctor of Science, a former Chief Naturalist at the Plymouth Laboratory of the Marine
Biological Association of the United Kingdom, a subsequent Professor of Zoology at the University of Liverpool,
came to stay from time to time over several years at the Mersea "Victory" while carrying out exhaustive research
into this unprecedented mortality among mature oysters. The author of the definitive work "Oyster Biology and
Oyster Culture" he was of course a very great expert in the field. He was a small brisk man with a keen sense
of humour, rarely to be seen parted from his pocket microscope. He had as an occasional assistant another
Professor, one Austin of the Indian Biological Association.
Between them, they evolved the theory - though they were unable to bring it to final incontrovertible proof -
that the great slaughter of oysters, not only on the Mersea layings but on the beds of the Blackwater, the
Crouch and the Roach, was brought about by the post-Great War dumping on high explosive and poison-gas in
the Black and Barrow Deeps, only a dozen miles offshore. It was also fairly generally believed that the dumpers,
from idleness or carelessness, or conceivably stress of weather, had ditched part at least of their lethal cargo a good deal nearer to home than that.
The Professor's many attempts, backed naturally by the cultivators themselves, to obtain either compensation for their crippling losses or even acknowledgement of responsibility from any Government department, brought nothing but failure. In its habitual way Whitehall over-rode, when they did not suit its book or carry significant political weight, the findings of the expert on the spot.
Orton, among his many achievements, established by scientific research what had always been a matter mainly of
tradition and belief; that in its life-cycle the oyster changes sex from male to female within a year or so
when external conditions are healthy and the food suitable and sufficient.
He concerned himself both with the Natural History, and the eradication, of the greatest pest to oyster
cultivation that exists, the American Slipper Limpet. About the year 1800, quantities of American oysters were
imported into this country and laid down to fatten in the vicinity of the native grounds. With them arrived their
parasite, the Slipper Limpet, which thrived and spread - and spread destruction to the native stocks. Tons at
a time were dredged up from the Blackwater in the last century. It is a mater of belief rather than strick history
that certain oystermen of around that period, disgruntled at being refused a bonus for the destruction of the
pest, preferred to chuck back all the quantities their dredges brought up rather than put themselves to the
unremunerated trouble of destroying them. Pig-headed beyond belief - but the belief is there.
This attitude - if it ever did exist - has changed with the times. The cultivation of oyster grounds has become as
scientific as the cultivation of farms has become, with a total unrelenting war raged on the impressive and
possibly freakish-sounding roll-call of pests and parasites - the Slipper Limpet, the Whelk-Tingle, The
American Tingle, the English Rough and the English Smooth Tingle. It is probably not too much to say that
Professor Orton in his day did much to bring about this end.
Oysters are considered marketable at about three inches across when they are four years old - better still at
five, six or seven years. The Mersea Native is distinguished by its green beard, its plump and creamy body,
and its hard shell, from its Whitstable brother, whose shell is soft and whose beard is sandy-coloured. Orton
may have, and probably did, enquire into the nature, origin and causes of the differences, but his conclusions are lost.
Cleansing and purifying oysters was first introduced at Brightlingsea, and compulsorily at Mersea in 1960 after
an outbreak of typhoid. At first regarded with disgust and suspicion it is by now generally accepted that the
plumpness and flavour of the Mersea Native are improved by the process.