The explanation appears to be that the shallow and landlocked waters of the Zuider Zee, as well as the sea on the Dutch coast, become raised to a higher temperature in summer than any part of the sea about the British coasts, and that therefore anchovies are able to spawn and maintain their numbers in these waters.
Of anchovies alone, to,000,000 jars are prepared annually, while salted fish is, next after bread, the staple food of large masses of the population.
Many of the inhabitants are engaged in the carrying trade, while the fisheries on the coast are also actively prosecuted, tunny and anchovies being caught in great numbers.
There is no evidence to decide the question whether all the young anchovies as well as the adults leave the Zuider Zee in autumn, but, considering the winter temperature there, it is probable that they do.
There are numerous tile-works and potteries of fine ware; and a considerable trade is carried on in anchovies and oysters caught in the Scheldt.
Oysters and mussels are obtained on the East Scheldt, and anchovies at Bergen-op-Zoom; while salmon, perch and pike are caught in the Maas, the Lek and the New Merwede.
The occurrence of anchovies in the English Channel has been carefully studied at the laboratory of the Marine Biological Association at Plymouth.
Fishenies.The catching of tunnies, sardines, anchovies and salmon on the coasts employs large numbers of fishermen (about 67,000 in 1910), and the salting, smoking and packing of the first three give employment to many others.
When taken in British waters anchovies are either thrown away or sent to the market fresh with the sprats.
In the Zuider Zee small herring, flat fish, anchovies and shrimps are caught, the chief fishing centres being the islands of Texel, Urk and Wieringen, and the coast towns of Helder, Bunschoten, Huizen, Enkhuizen, Vollendam, Kampen, Harderwyk, Vollenhove.