Our Fish Immigrants 



395 



water is too cold to permit the eggs of the 

 transplanted 0)'sters to develop. In San 

 Francisco Bay, owing to the warmer 

 water, a small but apparently increasing 

 proportion of the output represents 

 oysters that have been produced locally. 



How large a factor in the Pacific states 

 fisheries the Atlantic oyster has become 

 may be appreciated when it is stated that 

 it is exceeded in value by only the sal- 

 mons, and that the annual output now 

 leaches $600,000 to $700,000. 



The soft-shell clam, accidentally car- 

 ried across the continent with the oyster, 

 has thrived well ; has been retransplanted 

 from California to Oregon and Wash- 

 ington, and is nowj'ielding the fisher- 

 men an annual income of about $30,000. 



UNITED STATES EISHES IN OUR INSULAR 

 POSSESSIONS 



It seems to be pretty definitely under- 

 stood now that the American Constitu- 

 tion does not necessarily follow the flag. 

 In this respect it differs from American 

 fishes, of which quite a number of species 

 have already become established in our 

 insular possessions and are enjoying all 

 the privileges accorded them at home, 

 while various others will doubtless in 

 time prove valuable additions to the 

 fauna of Porto Rico, Hawaii, and the 

 Philippines. 



While the fresh waters of the Ha- 

 waiian Islands are too small and unstable 

 to permit very extensive results from ac- 

 climatization, experiments have been con- 

 ducted with quite a number of species. 

 A single attempt to establish the large- 

 mouth black bass has been unsuccessful, 

 but there is reason to believe that this 

 fish may do well in some of the ponds. 

 Bullheads from California have been 

 planted in the same waters, and should 

 easily be established if desired. Frogs, 

 introduced as early as 1879, have become 

 abundant on several of the islands and 

 are now reaching the Honolulu market. 

 Besides their value as food, they have 

 proved beneficial to cattle-growers by 

 consuming large numbers of fluke-worms 



inhabiting the shores of the ponds and 

 pools. 



An especially interesting case of fish 

 acclimatization in outlying territory was 

 the recent planting in the rice fields of 

 the Hawaiian Islands of several thousand 

 viviparous and other minnows from 

 Texas, for the purpose of destroying mos- 

 quitoes. The mosquito-eating propen- 

 sities of these species at home are well 

 known, and it is reported that the fish 

 have given a good account of themselves 

 in Hawaii. 



In the spring of 1907 a consignment of 

 large-mouth black bass left San Fran- 

 cisco for the Philippine Islands, where 

 the fish will be planted in closed waters 

 pending a determination of the best 

 points at which to liberate them and 

 their progeny. 



Among the Asiatic fishes now com- 

 monly found in the Hawaiian Islands are 

 the carp, the gold-fish, a cat-fish, and a 

 serpentheaded-fish — all introduced by 

 Chinese or Japanese and used chiefly by 

 those people. The carp and the gold-fish 

 have also been introduced by them into 

 the Philippines. 



FOREIGN FISHES IN THE UNITED STATES 



The introduction of foreign water ani- 

 mals into the United States has been 

 much less extensive than the importa- 

 tion of plants and land animals, the pri- 

 mary reasons for this being the greater 

 difficulties of transportation and the all- 

 sufficient richness of our own waters in 

 almost every kind of products. Quite a 

 number of Old World fishes have been 

 successfully planted in our waters, and 

 some of them have become very well 

 known in various parts of the countr3^ 

 The introduction of several others has 

 been attempted, but has met with failure. 



Two of the best-known European 

 trouts — the brown trout and the Scotch 

 lake trout, or Loch Leven trout — have 

 been cultivated in the United States for 

 a score of years by both national and 

 state fishery bureaus. These fish have 

 been planted chiefly in private waters, 

 some of which have been well stocked ; 



