156 



Life 



Island about 300 miles south of Los Angeles 

 (Bartholomew and Hubbs, 1952). Formerly 

 the sea elephants were far more abundant 

 than now, but organized killing of them for 

 their oil brought them nearly to extinction 

 by the end of the nineteenth century. The 

 northern fur seals (really sea lions) which 

 once were present off southern California 

 were brought even closer to extinction until 

 given international protection in the Pribilof 

 Islands, and the Guadalupe fur seal was 

 thought to have been exterminated until a 

 few survivors were found recently. The fur 

 hunt also brought the sea otter almost to ex- 

 tinction a half-century ago. All these mam- 

 mals are now protected by law and all are in- 

 creasing in number, but they have not yet 

 reached their former numbers, as is indi- 

 cated by the still abandoned hauling-out 

 grounds where rocks have been highly pol- 

 ished by the sliding of generations of ani- 

 mals. A point of geological interest is the 

 service of all as minor geological agents in 

 transporting pebbles that are picked up, 

 probably to aid in the trituration of fish 

 bones, performing much the same function 

 as sand in a chicken's crop (Emery, \94\b). 

 Dolphins, porpoises, and whales are mam- 

 mals that live a wholly pelagic life. They 

 bear and nourish their young at sea and 

 never come ashore. In fact, whales can 

 exist only where water aids in supporting 

 their bulk, for they cannot lift their unsup- 

 ported weight sufficiently to breath. Dol- 

 phins in the region are seen most frequently 

 at the bows of ships, whose speed they gen- 

 erally can exceed. Gray (1957) reported 

 that the closely related Atlantic dolphin has 

 been clocked at 22 miles per hour, and there 

 are many unconfirmed local reports of 

 greater speeds for dolphins off southern 

 California. Ordinarily, the dolphins and 

 porpoises race up to the bow of a ship 

 where they maintain position a few feet to 

 one side or the other, seemingly with little 

 effort and possibly by riding a form of bow 

 wave. During their stay at the bow they 

 signal to each other or use squeaking noises 

 as a sort of radar; these noises are readily 

 detected as whistles and grunts on the ship's 

 echo sounder. After tiring of the ride, per- 



haps because of its slowness or wrong direc- 

 tion, the dolphins and porpoises break away 

 at an angle and rapidly disappear in the 

 distance. Following each other in single 

 file and arcing up to breath, they look like a 

 monstrous sea serpent and may well have 

 inspired some of the tales of sea serpents. 

 The total number of dolphins and porpoises 

 is very uncertain, but Norris and Brown (in 

 press) have counted an average of about 

 8000 sightings per year, mostly in the Cata- 

 lina Channel. Several sightings of the same 

 individuals may have occurred, but in com- 

 pensation the area of observation is a small 

 fraction of the whole region. 



Whales are common in the region (Fig. 

 136), and during the past century they were 

 beached and rendered into oil at Gaviota, 

 Ballona Greek, Portuguese Bend near Los 

 Angeles, and San Diego (Scammon, 1874). 

 According to Gilmore and Ewing (1954), the 

 gray whales also used San Diego and prob- 

 ably Mission Bay as calving grounds, al- 

 though bays farther south were used more, 

 and some are still being used. For several 

 years Gilmore (1956^) has made an annual 

 census by counting the gray whales in their 

 fall procession southward past Point Loma. 

 Apparently they move from point to point 

 during their migration and mostly do not 

 follow the curving shores between points. 

 A few humpback, finback, sperm, and blue 

 whales visit the region and some remain 

 during the summer. Visits of right whales 

 are very rare (Gilmore, \956b). 



Bones of sea mammals are common con- 

 stituents of phosphorite dredged from bank 

 tops, with the dense whale earbones nearly 

 as abundant as shark teeth. In this respect 

 the slowly deposited sediments of bank tops 

 are similar to the red clays of the deep 

 sea where many elasmobranch denta and 

 cetacean otoliths are found (Eastman, 1903). 

 Fossil sea mammals are also known from 

 Tertiary strata of California, and some of 

 them are now extinct according to descrip- 

 tions by Kellogg (1931) and Downs (1956). 



Although not nektonic in the sense of 

 fishes, the sea birds have much the same re- 

 lationship to plankton as fishes. This is 

 much more true of albatrosses, petrels, and 



