Additional Notes – Areas of Lower Biological Diversity:

  Of considerable interest are the three areas of lower ecological diversity and biological transition that occur in between the areas of higher biodiversity.

Area #1: Starting in the north Florida Peninsula many temperate species decline and reach the southern limit of their range.  Many sub-tropical and tropical species also reach the northern limit of their range in this area.  Ecosystem types and diversity also decline in this transitional area.

Area #2: The central Gulf Coastal area of Mississippi and Louisiana also contains fewer species because of the lesser diversity of habitat and ecosystems.  This large region is dominated by wetland ecosystems and the Mississippi river floodplain.  With less habitat diversity fewer species are found here.  It is also the most northern and central area of the Gulf Coast with less species reaching it from the east and west. 

  However, of interest is the role that the Mississippi river plays by allowing many deep southern species a corridor northward as far north as areas of Tennessee, Kentucky and even southern Illinois.

Area #3: The third area of lesser ecological diversity occurs along the central Gulf Coastal region of Texas.  This area is similar to what occurs in the northern Florida Peninsula.  In this area many eastern species reach the westward limit of their range.  Also, many western species reach the eastern limit of their range.  Many temperate ecosystems also decline in number providing less habitat diversity for fewer species. 
 
                    Map #3: Areas of Lower Biological Diversity (along the Gulf Coast).