304 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1947 



Small schools of the black-banded damsel fish, Dascyllus aruanus, 

 when disturbed, seek shelter in closely branching coral heads. They 

 remained within it while we broke loose from the bottom the entire 

 growth in order to carry it ashore. There the coral, with its fish and 

 crustacean inhabitants, was broken into fragments, and its denizens 

 were picked up without a single individual escaping. 



Swimming in schools over these broad, sandy stretches are yellow- 

 streaked goatfishes, harvest fish, threadfins, jacks, mullets, lizard 

 fishes, sand perches, and sometimes a few flatfishes (Bothidae) . Cruis- 

 ing around individually are black-tipped sharks. In holes in the 

 sand can be seen a species of large goby with a prominent blue streak 

 across its cheek. Snake and worm eels burrow in the loose gravel 

 and sand of the bottom. Giant tridacna lie on the bottom, with their 

 beautifully iridescent mantles exposed to the flickering sunlight. 



Big sting rays occasionally are seen on the bottom in 10 to 30 feet of 

 water. Vernon E. Brock, assisted by Dr. Kobert Hiatt, speared one oflP 

 Eman Island in 20 feet of water, while skin diving. The capture of 

 this dangerous fish, with its venomous sting, was a remarkable feat. 

 Brock swam down over the fish and drove a spear into it, then grabbed 

 the end of the spear, pulling the hundred-pound creature toward the 

 surface, but had to come up for air, and it went down. Once again 

 he tried, and this time with Dr. Hiatt's aid brought it up, all the time 

 keeping away from the lashing tail of the ray. After a desperate 

 struggle, it was speared again and finally brought alongside the row- 

 boat from which they were operating. It is now preserved in the 

 United States National Museum along with about 50,000 other fish 

 specimens collected during 1946 and 1947 in connection with the atom 

 bomb experiments. 



OORAL AND ALGAL AREAS 



From this somewhat barren sandy habitat, there occur all gradua- 

 tions in abundance of coral heads with algae up to the stage where 

 they are so close together that there is scarcely room to step between 

 them. More often the channels between the corals are 3 to 15 feet 

 wide, and some reach 30 feet or more in width. This type of habitat 

 may occur in the lagoon, in the wide passes, or on the ocean side of 

 the atoll rim. 



Where the corals and algal growths are luxuriant, over 200 species 

 of fish occur and were regularly captured through the use of rotenone. 

 However, during 4 hours' work, the maximum number taken at a 

 single station was 136 at Erik Island, Bikini Atoll. 



Although the smallest fish known, a fresh-water goby from the 

 Philippine Islands, is not found at Bikini, one of its relatives is a 

 close runner-up. The Philippine goby measured 9 or 10 millimeters 

 (three-eighths of an inch), whereas the smallest Bikini fish, the goby 



