11-25 



New Jersey, the Virginia muskrat in the Central Atlantic States, 

 and the Louisiana muskrat in Alabama, Mississippi, Louisiana, 

 and Texas. Secondary in importance are the raccoon, mink, and 

 otter. 



The dependence of waterfowl on the estuarine zone is both complex 

 and incompletely understood. The primary sport species, such as 

 mallards and canvasbacks, have been successfully adapted to man- 

 made changes in their environment, particularly those changes not 

 affecting the nesting sites. 



The ornamental shore and sea birds are a particularly aesthetic 

 attraction among the national fauna. These birds are generally 

 more dependent upon estuarine conditions than the more mobile 

 waterfowl and, in addition, have demonstrated a considerably 

 greater sensitivity to the overall encroachment of man. These 

 birds include whooping cranes, pelicans, bald eagles, egrets, 

 ibis, and many others. 



Governing Subdivisions of The Biophysical Environment 



Solar energy and gravitational energy are the basis for 

 everything that happens naturally in the estuarine zone. This 

 discussion of the biophysical environment has been concerned 

 primarily with the environmental conditions surrounding the trans- 

 formation of these energies into forms useful in living processes 

 and exploitable by man. Three different sets of subdivisions of 



