22 



CEYLON PEARL OYSTER REPORT. 



upon which we uow rely for the next immediate fisheries, appeared when first seen 

 (February, 1902) to be from 2 to 6 months old. Besides having invaded the Western 

 Cheval, immense quantities were found on the South and North-central, South and 

 South-east Cheval regions, and also upon the two Modragams, as well as upon many 

 of the southern banks extending from Negombo to Karativo. 



In November, 1902, the numbers on the Western Cheval bank were given by 

 Captain Legge as 57,605,000, occupying 936 acres, but, owing to bad weather, the 

 whole of the bank was not surveyed. No other numerical estimate was made till 

 Mr. Hornell's inspection of this year, when a very careful estimate placed the 

 number remaining at 35,000,000 upon 1122 acres. Tabulation of the above facts 

 shows this history clearly.* 



The discrepancy between the estimates for 1901 and March, 1902, appears largely 

 explicable by the estimate of oysters per dive having been either too low for the 

 former year or too high for the latter, estimates being liable to variation with every 

 condition that affects a diver's powers of working. Divers have been known to bring- 

 up from one particular spot only 10 oysters per dive when the weather conditions were 

 unfavourable, and yet the following day, the sea being calm and warm, the same men 

 would report double the number. To arrive at accurate estimates, the weather 

 conditions, if adverse, should be allowed for, and the total number increased 

 accordingly. 



In November, 1902, the encroachment of the younger generation had markedly 

 increased, and with the growth of the smaller ones many portions of the Western 

 Cheval bank the parts where they were most abundant had to be transferred from 

 the category of regions bearing maturing oysters to those monopolised by the younger 

 generation. 



" In February, 1903, no regular inspection was made of these latter regions, but by 

 means of numerous descents in a diving dress I was able to obtain a fair knowledge 

 of the distribution of the younger oysters. On the Cheval and the North and South 



* See also Part II. of this Report (1904), p. 15, and figs. 9 to 14. 



