394 BULLETIN OF THE UNITED STATES FISH COMMISSION. 
As a fattening ground for oysters this locality is regarded as not a little depend- 
ent upon the outcrops of the Sheppey clays, as these may naturally be regarded as 
furnishing the pabulum for the rapid development of the minute plant organisms which 
become the food of the oyster. 
The northern or Essex side of the Thames estuary receives a series of small incur- 
rent rivers and is, therefore, in its shallower portions slightly fresher than the waters 
of Kent. Production of seed oysters appears to be most successful in and near the 
mouths of these rivers, where, other things being equal, the density is lower ( i . e., 
about 1.022 to 1.023).* This oyster region is famous at three ports — the river Crouch 
near Burnham, the Blackwater, and the Colne near Brightlingsea (Colchester); notes 
upon the cultural measures at these localities will subsequently be given. 
The natural oyster-grounds have not escaped the fate of those of neighboring- 
countries during the period of their public dredging. The region of the Thames, 
notwithstanding its fertility, could not endure the increasing strain upon its resources, 
caused by the demand of the neighboring London market. The effects appear to have 
been felt tirst at Whitstable, as the district whose oysters were most sought for, 
and not unnaturally caused this center to become the depot of the producing region 
of the Thames, draining its supplies for growing and fattening from the Colne (1866), t 
the Blackwater, and the Crouch. Here too the effect of overfishing soon became 
evident; the natural oyster- grounds were exhaustively dredged and the quantity of 
seed oysters became less and less. All British estuaries were now, one by one, 
laid under contribution by the increased demand, until at length their natural 
resources became overtaxed. The demand had then to turn to the continent for its 
principal supply of seed oysters, which had there come to be produced cheaply by 
artificial means. 
As the natural beds have at all points been depleted, so have the chances of a 
heavy natural spat| appeared to grow less and less; popularly this dearth of spat is 
generally attributed not more to overdredging than to the lack of favorable or “spat- 
ting” seasons (i. e., warm summers with absence of storms or winds), and the excep- 
tional years of 1858, 1859, 1866, and 1881 are looked upon as direct proofs of climatic 
influence. The reappearance of “ spatting ” years is generally looked upon as posi- 
tive, although irregular in occurrence to a noteworthy degree, in general, however, 
to take place “ three times during a lifetime.” This firm belief in the n'atural and 
unfailing productiveness of the oyster-grounds has only been equaled by the dredger’s 
steadfast view, which gives him birthright from the days of Magna Charta, to fish as 
often as possible upon the public oyster banks, and to resent as a personal injury 
all authority to reserve lands for the purpose of benefiting everybody. It may, of 
* These densities correspond very closely to those of Auray and Arcachon, the regions of produc- 
tion in France, and are similar to those of production at Tarente (p. 359). The sp. gr. at Burnham 
(August 15) did not exceed 1.021 at 64° F., at Brightlingsea 1.023 to 1.025 at 65° (August 16). The 
writer was told by Mr. Newman of Colchester that the Colne waters during the early spring months 
are perceptibly freshened. 
t Philpots’ ‘‘Oysters, and all about them,” London, 1892, p. 366. The price of Colchester seed is 
here recorded as $1.50 per “ tub ” (20 gallons) in 1859, and about $2 in 1885. The price at present is 
about $10 per bushel. 
IThis view appears to be, with limitation, that of Prof. Huxley. Cf. Eng. 111. Mag., Nov., 1882, 
article on Oysters and the Oyster Question. 
