Binl.s — Our Liviiii; Rc.\<ninc.\ 



Increase 



Fig. 1. Nuniher ot states with popiilalioti trends either Jeclining or increasing for 27 songbirds. 



cedronint]) (Fig. 1 ). This situation may be due to 

 tlie fact that the grassiantj and early succession- 

 al habitats are being modified, while ornamental 

 fruiting bushes, shrubs, and trees planted in 

 urbanized areas may be benefiting the increasing 

 species (Beddall 1963). The explanation, how- 

 ever, is certainly more coinplex than this, given 

 that some birds do not fit the pattern. For exam- 

 ple, the American pipit {Antlnts nihcsccus), 

 which eats berries, crustaceans, and mollusks 

 (Ehrlich et al. 1988), is decreasing in four states 

 and increasing in none (Fig. 1 ). 



To evaluate the areas of the conterminous 

 states showing increases or decreases in their 

 bird populations, we counted the number of 

 species showing a population change in each 

 state and then calculated the percentage with 

 respect to the number of the 27 species occur- 

 ring in each state (Fig. 2). A total of 24 (309f ) of 

 the states has greater than .'1% of these wintering 

 bird species showing positive population trends, 

 while 32 (67%) show declines of similar magni- 

 tudes. 



Mapping the percentages (Fig. 3) indicates 

 that the largest increase is in South Carolina, 

 with the far western states, those in the north- 

 central region, and a scattering of states in the 

 eastern portion of the conterminous states show- 

 ing positive population trends. 



The largest decreases (Fig. 3) are in South 

 Carolina, Georgia, Florida, Alabama, Louisiana, 

 and Delaware. The Pacific states, those in the 



Fig. 2. Number and percentage of 27 birds showing deehning and increasing population trends. 



