MARINE BIOLOGY ON THE 

 PACIFIC COAST 



BY CHARLES ATWOOD KOFOID 



Professor of Zoology, University of California 



PHYSICAL Conditions. — The Pacific Coast of Ihe 

 United States presents in the main a bold 

 line of cliffs mostly of the later geological 

 formations, with relatively few protected waters 

 south of Puget Sound. This results in a paucity 

 of the stable granitic substrata and of collecting 

 ground sheltered from the turmoil of the breakers. 

 These conditions give a barrenness more apparent 

 than real to the littoral area, and considerably in- 

 crease the inaccessibility of the littoral fauna. 



The relatively small Arctic contribution to the 

 California Current which sweeps southward along 

 the coast permits, for the northern latitude, rela- 

 tively high surface temperatures ranging from 8° 

 in March to 14° in August at the Canadian boundary, 

 and from 15° in January to 18° in August at San 

 Diego. The earth's rotation and the local con- 

 figuration of the ocean bottom in sunken valleys 

 favor the local upwelling of colder and richer 

 water from the depths at certain points along the 

 coast, notably at Monterey, Cape Mendocino, and 

 San Diego. This moderates surface temperatures 

 in the south and adds greatly to the enrichment of 

 the local faunas both pelagic and littoral. These 

 temperature conditions affect profoundly the nature 

 and abundance of the fauna, giving to the north 

 an exceedingly rich fauna with many individuals, 

 and to the south an exceedingly varied fauna rich 

 in species. Many species of the faunas of Alaska 

 and Puget Sound extend southwards along the coast 

 into progressively deeper water, as, for example, 

 in the case of the rat-fish (Chimaera collei) which 

 is caught at the wharves in Alaska but only in 

 50-100 fathoms off San Diego. 



The relatively narrow continental shelf, the in- 

 frequency of coastal indentations, and the absence 

 of large rivers in the south, make the marine fauna 

 of the Pacific Coast pre-eminently an oceanic one 

 and bring the pelagic fauna of the high seas within 

 easjr reach of the biologist, pre-eminently so at 

 Pacific Grove and San Diego. 



Aquaria and Marine Biological Stations of the 

 Pacific Coast. — Six marine biological stations for 

 instruction or research are located on the Pacific 

 Coast. 



124 



