LIFE IN THE OCEAN CLARK 371 



If the 30 tons represented bj r a very large whale were incorporated 

 in the bodies of cattle, these cattle would require for their support 

 each day the amount of fats and carbohydrates present in the hay 

 yielded by an acre of good meadow land in a whole season's growth. 

 A whale requires much less food than its equivalent in cows, since 

 it is entirely supported by the water and is much less active. On 

 the other hand, consuming only other animals, many of which them- 

 selves are two or three or more steps removed from a vegetable diet, 

 there is a very large wastage in the nutritive matter in the sea plants 

 before it enters the whale. We shall assume that the latter offsets the 

 former. 



The State of Rhode Island has an area of 1,250 square miles. If 

 this State were wholly planted in grass and yielded as much hay 

 per acre as the average meadow, enough food would be produced in 

 the course of a summer to support a maximum of about 2,150 of 

 these great whales for a year ; the District of Columbia could support 

 less than 125. 



Yet whales are abundant in certain regions. I have myself seen 

 on the Pacific more than 100 at one time, though these were of a 

 kind much smaller than the blue whale. At the height of the whale 

 fishery at Spitsbergen the catch averaged slightly over 1,000 whales 

 a year, all large ones. The food of those that were killed, not con- 

 sidering those left alive, would represent the annual grass crop from 

 an area eight times the size of the District of Columbia. 



These rough calculations are sufficient to show that the pastures 

 of the sea must be very rich, for not only do the marine pastures sup- 

 port numerous whales of all sizes, but in addition various large 

 sharks, a number over 40 and one over 50, and said to reach 70, feet 

 in length, and other huge fishes which are not eaten by whales and 

 therefore compete with them for the food supply. And then there 

 are the seals and the sea birds and hosts of bottom-living animals 

 in many places forming living carpets for miles and miles, all 

 browsing, so to speak, directly, or mostly indirectly, on the same 

 pastures. 



It has been said that the marine pastures are richer than the 

 pastures of the land, and on occasion this certainly seems true; but 

 close comparison between the two is difficult. In the first place 

 sea animals require much less nutriment than those on land so that 

 comparison bulk for bulk between the two means little. Further- 

 more many whales and many of the larger fishes, like the mackerel 

 and the herring, are migratory creatures, wandering regularly, or 

 more or less irregularly, from place to place. On land the growth 

 of vegetation with us ceases in the winter, and in the Tropics is 

 much reduced in the dry season; nowhere is it uniform throughout 



