THE ANIMAL ECOLOGY OF THE COLD SPRING SAND 

 SPIT, WITH REMARKS ON THE THEORY OF ADAP- 

 TATION 



C. B. Davenport 



Cold Spking sand spit runs from the west shore of Cold Spring Harbor, Long 

 Island, eastward to within 100 or 200 feet of the eastern shore of the harbor. The 

 history of the formation of the spit is briefly this : Cold Spring Harbor (Fig. 1) is a 

 fiord-like re-entrant about ten kilome- 

 ters long, emptying at its lower or 

 northern end into Long Island Sound 

 about one-fifth of the way from Hell 

 Gate at New York city to " The Race," 

 south of New London. The Sound 

 itself, 175 kilometers long by 35 kilo- 

 meters broad at its widest point, and 

 having a prevailing depth of about 30 

 meters, receives large streams of water 

 from the north — the Connecticut, 

 Housatonic, and Quinnipiac rivers, 

 and many minor ones. These give 

 it a low specific gravity, 1.020, and 

 a muddy bottom. Long Island is 

 covered over its northern part with 

 glacial debris, forming hills that rise 

 to a height of over 100 meters. Be- 

 tween these hills streams flowing 

 north have cut valleys and, in the 

 general sinking to which the whole 

 area has been subjected, these valleys have become drowned, forming long, straight 

 but shallow harbors of which Cold Spring Harbor is an excellent type (Shaler, 1902). 

 Into the head of the harbor a small stream flows with a summer discharge of not far from 

 five cubic meters per minute. This stream is dammed thrice along its course of two 

 miles, so that the deposit that it carries into the basin above the beach is only fine mud. 



The effective winds at Cold Spring Harbor blow from the northeast and, striking 

 with violence upon the bluffs on the west side of the harbor, tend to wear them away. 

 The currents setting southward then carry this eroded material until it is dropped in 

 the shallow and protected waters of the upper end of the harbor, where the sand spit or 

 " beach" is now found. The inner harbor thus cut off is about 800 meters long by 600 



157 



40 c 53 



40 52 



Fig. 1.- 

 Beach). 



7J*« 

 -Map of Cold Spring Harbor, showing spit (Cold Spring 



