NO. 2 HARTMAN : QUANTITATIVE SURVEY 209 



LOS ANGELES-LONG BEACH OUTER HARBOR 



The Los Angeles-Long Beach outer harbor (LH) is a shallow, four 

 to nine fathom deep, artificially constructed basin, located between Ter- 

 minal Island and the San Pedro shelf. It is separated from the open sea 

 by a breakwater with openings which allow ships and seawater to move 

 freely in and out of the basin. Sediments in the bottom are mainly silty 

 to sticky muds and rubbly shales, except along the shipping lanes, where 

 hard sandy bottoms prevail. Benthic animal populations, taken with the 

 grab, are predominantly annelids of many kinds and in moderate to high 

 numbers ; they are accompanied by much smaller numbers of mollusks, 

 crustaceans, and sparse numbers of echinoderms. They are the same kinds 

 as those occurring more abundantly on the San Pedro shelf where the 

 quality of the sediments and proximity to food supplies are similar. 



The outer harbor receives much organic and waste materials from 

 the drainage of the Los Angeles and San Gabriel rivers. The effects of 

 pollution on bottom faunas in Alamitos Bay, an arm of the San Gabriel 

 River, have been studied by Reish (1955) ; the kinds and numbers of 

 animals are much like those in the outer harbor or the shallow, sandy 

 shelf (California, 1959). The fauna is fairly uniform throughout, de- 

 pending on whether sediments are chiefly mud, clay or sand. 



Seven samples were analyzed : 



1.1 Sta. 6107 (near no. 29), in 4 fms. OPG took 2.96 cuft of smooth, 

 black silty mud. Wet weights measured 28 grams, of which polychaetes 

 were 14.7, mollusks 5.4, enteropneusts 4.2 and pinnotherid crabs 3.7 

 grams. In addition to those listed on the chart, a cumacean ( 1 ), a pinno- 

 therid crab (17), and an enteropneust (6) were present. Largest species 

 were Glycera americana, an enteropneust, and Marphysa disjuncta. Most 

 abundant were Ancistrosyllis tentaculata (169), Haploscoloplos elon- 

 gatus (50), and Cossura Candida (35). 



2. Sta. 2314 (no. Z2) , in 4.5 fms. OP(i took 0.56 cuft of mud, silt 

 and many animals. A sea whip (1), ?Harenartis (24), two kinds of 

 nemerteans (10), amphipods (1), isopod (1), cumaceans (5), ostracods 

 (9), and a pinnixid (7), accompanied the species named on the chart. 

 Largest individuals were Asychis sp. and Praxillella affinis pacifica; most 

 abundant were Haploscoloplos elongatus (82), Liimbrineris spp. (61), 

 Tharyx tesselata (52), and Nereis procera (41 ). 



^In all charts, below, the first numbers (i.e. 1-7) refer to those used in the 

 chart-headings. Station numbers (1370 to 7726) are given in the LIST OF 

 STATIONS. The serial numbers, 11 to 267, refer to locations on the grid, vol. 19, 

 pt. 1, p. 6). 



