Table 7 Catch of Pearl Oysters (in sacks) "hy Gear and 



the Yield of Pearls in Carats 



the latter month the oysters that have already spa\im.ed are usually in poor condition. 

 Detailed observations on setting are not available. It is knov/n that young oysters would 

 set on any hard object with a clean surface. Grov;th is apparently raT)id. risfcemen and 

 pdninistrative officers concerned v;ith the pearl fisheries s,t Porlamar maintain that within 

 6 months young pearl oysters are already fully developed and may he fished. 



Hosoueira "believes that growth of pearls is also rapid, for about 85 percent 

 of all the pearls taken in one season are obtained from young oysters. He thinks the oyster 

 discards the old pearls by ejecting them from the mantle cavity. This interesting point 

 desei-ves further study as it is very important, from the point of view of management, to 

 knov/ more definitely hov; long the oysters retain the pearls. 



Frequent closings of grounds constitute serious handicaps for the development 

 of the industry on a more sound ba.sis. At present, pearl fishermen do not knov; until 60 days 

 ■orior to the openinc date of the season v;hether the grounds will be open to pearling. Con- 

 seouently, pearl fishing cannot be depended upon for a livelihood and becomes a secondary 

 occupation. Likewise, it is difficult to expect that anyone will invest money in improve- 

 tients of boats and gear without any ass\irance that he will have a chance to use them. 



SUGGESTED PLM OP BIOLOGICAL STUDIES 



Present law (Article 27, Cha.pter VII, Ley de Pesca de Perlas) authorizes the 

 conduct of investigations to determine the possibility of enlarging existing oyster grounds 

 and estrblishing new ones. Particular mention is made of the required participation in this 

 v/ork of -oearl fishermen who are obligated to contribute for this purpose 25 percent of the 

 shells. Inasmuch as no systematic v;ork of this type is being conducted at present, it is 

 ny suggestion that careftil consideration be given to the organization of such biological -and 

 ecologica!'- studies as are needed for the development of new pearl oyster grounds. The present 

 system is essentially that of an exDloitation of a natural resource, without any attempt to 

 atrply oyster cultural methods. We know, from the esperience in cultivation of edible and 

 pearl oysters in other countries, that an oyster population can be materially increased by 

 oyster farming technique. It is, therefore, reasonable to expect that the same beneficial 

 results ;naj'- be obtained in Venezuelan waters. As a first step in this direction, it is 

 necessary to obtain more detailed knowledge and understanding of local biological factors. 



First, more precise information is needed of the time and intensity of spav/n- 

 ing. Experience \iith other species of oysters shows that during the reproductive season 

 there are several periods of more intense spawning. Factors controlling the occurrence of 

 these periods sho^lld be carefully determined in order to be able to predict time of spawning 

 with a reasonable degree of accuracy. Like\irise, the attachaent of young oysters (setting), 



20 



