CHAPTER IX 



LIFE BETWEEN THE TIDES* 



The intertidal animals of Point Lobos are a fair sample of those which 

 inhabit exposed rocky shores from Central California to Southern Alaska. 

 The point thrusts ledges of hard rock fan-wise into cold turbulent water. 

 AVaves rush into narrow coves, dash high, and fall back in numberless 

 cascades. Except on the southern shore, where irregularities of the eroded 

 conglomerate provide shelter from the heaviest surges, there is little chance 

 for the formation of sizable tide pools and, hence, for tide-pool associations 

 at their best. The sides of the granite points are steep and offer almost a 

 maximum resistance to the buffeting and scouring action of great seas, 

 which in winter assail the coast with spectacular force until the ocean is 

 churned to whiteness. 



Under such conditions the only life which can survive is that adapted 

 by toughness to withstand shock and by structure to adhere temporarily 

 or permanently. Of course, many creatures are sheltered within rock 

 crevices, between closely crowded mussels, or in masses of kelp such as 

 Lessonia. 



Along the lower, southern shore of the Point the conglomerate rock is 

 much broken, affording a great variety of exposure, and often complete 

 shelter. At one place there is a small rocky beach uncovered at low tide. 

 Here and on Conglomerate Point will be found a considerable number of 

 small tide pools, the population of which varies with exposure to surf and 

 position above lowest tide level. In general, pools nearest low water and 

 least exposed to wave action contain the greatest variety of forms. 



It need hardly be stressed that the time to observe shore animals is dur- 

 ing low" water and when the Pacific is living up to its name. High tide or 

 high seas are avoided by the old hand. It may be even dangerous on a 

 difficult shore to approach too near the water, owing to the occurrence of 

 sporadic giant waves which greatly overreach the average and constitute 

 a serious peril to inexperienced persons. 



Animal life between tides is dominated by the invertebrates — creatures 

 lacking a backbone. Such are the sponges, anemones, worms, moUusks, 

 barnacles, crabs, sea stars, sea urchins, sea squirts, and numerous other 

 less conspicuous types. 



On wave-swept exposed rock such as the granite pyramid point three 

 rather conspicuous intertidal zones are readily observable. There is a broad, 

 somewhat bare, splash zone mostly above mean high tide; a broad dark 

 zone of mussels and kelp ; and below this a coralline zone exposed at lowest 

 tides and colored pinkish or reddish. On Protected shores this lowest zone 

 is very populous. 



• By \y. K. Fisher, when Director, Hopkins Marine Station, Pacific Grove, California ; and 

 James L. Leitch. 



Lace-lichens frame the path 



that leads to many areas frequented by 



birds of shore and seacoast 



(71) 



