OF CALIFORNIA PUB ICATfONS >^ 



UNIVERSITY 



IN 



ZOOLOGY 



Vol. 18, No. 2, pp. 27-43 December 12, 1917 



AN UNUSUAL EXTENSION OF THE DISTRIBU- 

 TION OF THE SHIPWORM IN SAN 

 FRANCISCO BAY, CALIFORNIA 



BY 

 ALBERT L. BARROWS 



CONTENTS 



PAGE 



Introduction and acknowledgments 27 



General distribution of Xylotrya in San Francisco Bay 28 



Recent incursion of Xylotrya into San Pablo Bay 29 



Dikes at Mare Island 29 



Wharf near Crockett 30 



Wharf at Oleum 31 



Physical conditions in San Pablo Bay 31 



Discharge of fresh water into San Pablo Bay 31 



Salinity of San Pablo Bay 33 



Temperature conditions in San Pablo Bay 36 



Relation of Xylotrya to salinity 36 



Conclusions 41 



Bibliography 43 



Introduction and Acknowledgments 



It is said that the shipworm was unknown in San Francisco Bay 

 in the early history of the port, and that wood-boring molluscs did 

 not become an extensive menace to marine woodwork here until some 

 years after the great increase in the shipping entering the bay which 

 followed upon the discovery of gold in California. Be that as it may, 

 a species of the Teredidae, Xylotrya setacea Tryon, now thoroughly 

 infests the main portion of the bay, and, as in other localities where 

 shipworms are abundant, this borer is a constant cause of damage to 

 marine timbering in this port. Another species of shipworm. Teredo 

 diegensis Bartsch, has also recently caused damage in the upper part 

 of San Francisco Bay. 



