Pearl and Chank Fisheries - A New Outlook in Survey and Fishing

Abstract

The Gulf of Mannar and the Palk Bay Zones of the east coast of the Madras state, particularly the area from Rameshwaram to Manapad, are of very great fishing importance as far as the pearl and chank fisheries are concerned. The submarine plateau of the inshore areas of the sea here affords excellent habitat for the growth of the shell fish, Xnrcvs pyrum (Linn.) (the sacred chank) and Pivcunla jucaia (Gould) (the pearl oyster). Chank fishing and pearl fishing in this zone had been conducted from time immemorial under the control of the State. All along the stretch of the sea-bottom, extensive, flat rocky patches occur at a distance of 8-12 miles from the shore within 7-12 fathoms, separated from one another and surrounded by equally extensive patches of fine sandy areas at the same or slightly deeper zones. Whereas the chanks prefer fine and soft sandy areas called locally 'Poochi-manal' or 'pirals' as their abode, the oysters are sedentary and are attached to hard rocky substrata called'Pa ar'. Occasionally tfe one is found in the natural habitat of the other. There are more than 65 well known'Paars' (rocky sea-bottom) and lesser in number of good chank grounds in the Gulf of Mannar known to fisherman by their depth and location fixed by land bearings. The sea bottrm on Palk Bay side is not rocky, at the same time less shallow also. The chanks rrowing in this zone are classified as 'Patti' variety which is priced less than the 'Jadhi' variety fished from Rameshwaram to Tiruchendur. The differentiation between these two lie in the latter being elongate, elegantly formed, comparatively narrower and with well balanced spire whereas the former is with a short spire. The Tirunelveli and Ramanathapuram chanks now constitute the bulk to meet the demand from Bengal for chank bangle industry