particular oysters were harvested in Princess Bay, Staten Island, New York, in 

 1871; Collins (1892) gives the date as approximately 1869; and Hanna (1939), about 

 1870. This shipment overstocked the San Francisco market, and surplus oysters 

 were planted in San Francisco Bay. The oysters grew well and importation 

 continued. At one time transportation of young oysters reached enormous pro- 

 portions; and oysters were planted in many parts of San Francisco Bay as well as 

 in other inlets along the coast where they developed readily to markelable size 

 (Hanna, 1939). U .ci nerea are thought to have been introduced, if not in this 

 first shipment, certainly on subsequent ones. (Townsend, 1893; Walter, 1910; 

 Dall, 1921; Hanna, 1939). It was first recognized in California waters by Town - 

 send (1893) who wrote that it was becoming troublesome at this time on oyster 

 beds in San Francisco Bay, particularly in the southern part of the bay where drills 

 were most abundant. Stearns (1900) thought that the oyster drill was discovered -on 

 the oyster beds near Belmont on the westerly shore of San Francisco Bay as long 

 ago as 1889 by Townsend; however Townsend' s own report (1893) implies a much 

 earlier date. Hanna (1939) states that Uro salpinx was collected on the Alameda 

 flats in 1898, on oyster beds near Belmont in 1889, and near Redwood City in 1899. 

 Smith in 1907 noted that the oyster drill had become very abundant and several 

 years earlier was reported to be destroying oysters at a rate of 30 thousand dollars 

 annually. At this time oyster seed was still brought yearly from New York and 

 vicinity for planting. 



Orcutt (pers. com.) has kindly provided data on the present distribution of 

 U. cinerea in California, where its distribution coincides in time and place with 

 major plantings of oysters from the Atlantic coast. The practice of planting eastern 

 seed oysters in San Francisco Bay established in 1871 continued until 1900. From 

 1900 to 1932 half grown oysters were utilized. Now Urosalpinx is found generally 

 throughout South San Francisco Bay,, In Tomales Jiay there is an area which has 

 been used to hold full grown eastern oysters for the San Francisco market since 1875, 

 These grounds, approximately 500 acres in size, are heavily infested with the oyster 

 drill. In Areata Bay (North Humboldt Bay) in northern California there is another 

 area, of approximately 200 acres, which has been diked and over which eastern 

 oysters were planted in 1910 and 1911 and again in 1935 and 1936, which also 

 supports U. cinerea . It is important to note that areas of oyster culture in 

 California where other than imported eastern oysters have been cultured, do not 

 appear to support the eastern drill . 



On the other hand there have been small importations of eastern oysters 

 planted in other locations in California waters in which the drill has not been 

 reported to date. This suggests that Urosaljinx may not be able to adjust to these 

 habitats, or that insufficient drills were imported to colonize the areas . Since 

 the drill is able to establish itself in waters in which the eastern oyster does not 

 reproduce, as in most waters of the west coast, the latter is the more likely explana- 

 tion. 



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