The Grey Mullets of Kayamkulam Lake, India, and Their Fishery

Abstract

AFEW of the more common species of southern Indian mullets were recorded by Day (1865, 1878) and a more detailed report was made by Whitehouse (1922). Studies on the systematics and bionomics of mullets in Bombay, Calcutta, Baroda and Madras were reported by Fowler (1929), Pillay (1949), Chacko (1949) and Sarojini (1951). Except for the recording of a few species by Pillai (1929) and by the author John (1948), very little work has been done on these fishes in the Travancore-Cochin region. This area has extensive backwaters which provide ideal conditions for a large and varied mullet population. Kayamkulam Lake is a narrow stretch of shallow backwater situated midway between Quilon and Alleppy, Travancore. It is about 10 miles long, % to 1jf miles wide, 23j to 3 feet deep at low tide, and roughly 10 square miles in area. It is separated from the sea by a narrow strip of coastal land which tapers to a bar near its southern end. The bar remains open for about nine months and is closed about the middle of May. The bottom of the lake is largely sandy but overlain by silt, and in the deeper parts there is soft dark clay with a little admixture of fine sand. In such regions the vegetation is poor, except for an encrustation of the blue-green alga Oscillatoria. The shallow sandy regions, however, have a luxuriant algal growth, especially during the hot months. The lake is highly saline for the greater part of the year. The shallow warm waters, with abundant vegetation and plankton, form an ideal feeding ground for both adult and fingerling mullets. A study of the species is important for controlling, conserving and developing any fisheries. This work was therefore undertaken with