REPORT OF THE FISH AND GAME COMMISSION. 63 



I)resi'nt, thougli several of the eastern species have been carefully in- 

 vestigated, no facts concerning tlie age or rate of growth of a single 

 native Pacific species are known. 



In an attempt to remedy this lack, data have been collected through- 

 out the year on the Pismo clam, one of the most important California 

 species, and these are now being carefully studied. The preliminary 

 work indicates the main features of the age and as soon as it can be 

 completed it will be put in form for publication. It appears that the 

 growth is less rapid than has been supposed and that a considerable 

 age is reached by the larger specimens met with. 



A careful survey of the coast has forced the conclusion that few of 

 the native species can be materially increased by artificial means, but 

 that in certain suitable bays the "farming" of the introduced soft 

 shell or long clam might be made very profitable. Its culture has 

 passed the experimental state on the eastern coast and profiting by this 

 experience many acres of otherwise barren tide flats might be made to 

 yield as sure and valuable a crop as a wheat field. It is hoped that in 

 tlie future the question of the control of suitable tide lands may be put 

 on as secure a basis as is the management of existing oyster lands, thus 

 making such clam farming a practical possibility. 



Oyster Investigations. 



During the past year Dr. Harold Heath has been employed on in- 

 vestigations relative to the propagation of our native California oyster. 

 The larger Eastern oyster has never yielded to efforts to propagate it in 

 this state for the principal reason that our waters during its spawning 

 season are entirely too cold. It has been necessary, therefore, for the 

 growers of Eastern oysters to keep their beds stocked by bringing out 

 the spat or seed oysters from the Atlantic coast. After the oysters 

 have reached the size known as "si)at" they will thrive in our waters 

 but the younger larval stage can live only within a narrow range of 

 temperature which is above that reached by the water in any of our 

 bays where oyster raising has been tried. Our smaller native oyster 

 on the other hand, propagates within a comparatively wide range of 

 temperature and breeds naturally from San Diego Bay to Alaska. It is 

 known in the far North as the "Canadian oyster," in "Washington as 

 tlie "Olympia oyster" and in this state as the "California oyster." 



In Washington much progress has been made in raising this Pacific 

 Coast oyster and by means of expert advice the industiy has been 

 made quite profitable. Choice oyster bottoms on Puget Sound are 

 valued as high as $4,000 per acre. 



The only place in this state where it has been at all profitable i.. 

 gatlier the native oyster is on Tomales Bay, Marin Countv. Although 



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