Data of the yield of pearls are even less relia^ble, for freo_uently the purchase 

 of a lot of pearls was done privately without aaking axi^r official record of the trans- 

 action. V.'ith these liraitationsi the statistical data are useful in shov/in^ the declining 

 trend of the pearl fishery during the last tv/enty years (Tig. l) . The detailed data, 

 su-DTilied hy the Direcci(Jn Estadfstica y Censo, are sumnarized in Tahle 1. Tv;o factors 

 may have caused the v/ide fluctuations in the Quantities of shells exported from Panama 

 shown by these data: increase or decrease in the d.eLiand for PanaEa shells in the world 

 market, and the aliundance or scarcity of pearl oysters on the grounds. The quantity of 

 shells shown hy official record of export in 19I8 is entirely out of the range of the 

 fluctuations for the preceding and suhseq^uent years and cannot he explained hy any special 

 conditions v:hich nii^ht have affected the fishery at this time. Although this figure was 

 checked several tines hy the staff of the Office of the Direcci(Jn Estadfstica and found to 

 correspond with the data entered in the hookSf there is admittedly some error in records. 

 Of nore interest are the several sharp declines in- the export of mother-of-pearl shells 

 for the years igi'+'lSl?. 1921, 1923i and 1531. Low figures for I91I4-I917 are undoubtedly 

 due to the World War I in Europe, while a temporary decline in 1923 ciay he attributed to 

 unsettled economic conditions in Germany, the principal country importing Panamanian 

 mother-of-pearl shells. Thus, decline for I923 probably was caused by market conditions 

 rather than by the scarcity of oysters. Steady decline in the production of shells after 

 the peak of I925 is due, hov/ever, to the general decline in the supply of pearl oysters. 



Tears of forced inactivity from 1939 to 19'^3 inclusive had no beneficial effect 

 on the oyster population. In 19'+^'^5» when the fishery was officially resumed, the divers 

 found the pearl oysters extremely scarce. They also reported seeing, on several formerly- 

 productive grounds, many dead or dying oysters. It ha.s been the aim of the present 

 investigation to determine the cause of the existing depletion and to suggest the methods 

 of restoring the fishery. 



Tigure 1 Quantity and value of nother-of-pearl shells exported 



from Panama in I905-I9U7. 



