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ECOLOGY AND WILD LIFE CONSERVATION 



Atlantic Ocean in great numbers, and great flocks of ducks and geese 

 winter along the coastal marshes of Louisiana. 



Grasslands Biome. The great plains extend from central Texas 

 north into Canada. This region is characterized by light annual rain- 

 fall and rapid evaporation, conditions which are not favorable to the 

 growth of large trees. In many parts of Wyoming or western Kansas 

 one can look for miles in all directions without seeing a tree. Sagebrush 

 and cacti are dominant plants in many areas. Grasses grow in bunches 

 in the drier areas with bare spaces in between. Formerly the principal 

 animal was the American buffalo, whose place today has been taken by 



Photo by Winchester 



Fig. 30.3. The bison or American buffalo. This great bull watches over a herd in 

 Yellowstone Park, a small remnant of the great herds that once roamed our mid- 

 western plains. The bison probably had much to do with extending our plains region 



because of their grazing habits. 



cattle and sheep. The most interesting large mammal is now the ante- 

 lope, and the coyote is the chief carnivore. The sage grouse and the 

 prairie chicken are typical game birds. 



Desert Biome. Portions of California, Nevada, Arizona, and west 

 Texas are characteristic of the desert region where cacti, yuccas, Joshua 

 tree, creosote bush, and other typical, dry country species grow. The 

 saguaro cactus or giant cactus is the chief species but its range is limited. 

 Many southern species of animals penetrate the United States only in 

 this region. Snakes and lizards including the Gila monster are espe- 

 cially common. A long-tailed running bird, the road runner, preys on 

 the snakes. The cacti are the home of many species of birds, such as 

 the cactus wren. 



