EASTERN SHARP-TAILED SPARROW 795 



AMMOSPIZA CAUDACUTA GAUDACUTA (Gmelin) 



Eastern Sharp-tailed Sparrow 



PLATE 44 



Conlributed by Norman P. Hill 



Habits 



The sharp-tailed sparrows are re thing and wary inhabitants of 

 Atlantic coastal and some mland marshes; however, though common 

 or even locally abundant, they are little known. The casual visitor 

 to the seashore has scant reason to roam through the mud, silt, and 

 grass of their habitat. Hence these bhds remain secure and unob- 

 served except by boatmen and hunters who know them as "grass 

 finches." Even when one is accidentally Hushed, it quickly drops 

 back into cover and patient field work is needed to provide a satis- 

 factory study of this handsome but mouselike bh'd. 



The sharp-tailed sparrow as a species occupies as its breeding 

 grounds a great, though discontinuous arc in eastern and north-central 

 North America. This extends from Vhginia northeastward to the 

 St. Lawrence River, then skipping a gap of unsuitable territory, 

 northwestward to James Bay and, finally skipping another gap, 

 westward to the Canadian prairie provinces. Within this area the 

 A.O.U. Check-List now recognizes five distinct populations or sub- 

 species, each varying shghtly from the other morphologically, mainly 

 in color. In their life histories, habits, and behavior the five forms 

 vary but little. Hence most of the available information on the 

 nesting, food, enemies, and other essentials shared by all five are 

 presented here under the nominate race, which also happens to be 

 probably the best known and most thoroughly studied of the five 

 subspecies. 



The sharp-tail and the congeneric seaside sparrows are members 

 of the "grassland group" of Emberizine finches. This group, which 

 also includes the genera Passerculus (Ipswich and Savannah sparrows), 

 Ammodramus (grasshopper and Baird's sparrows), and Fasserherbulus 

 (Le Conte's and Henslow's sparrows), is fahly well separated from 

 all other finches in habits and morphology as well as in habitat. The 

 sharp-taUs and seasides may be considered the salt-marsh repre- 

 sentatives of the group, though each is occasionally found in fresh 

 water marsh habitats, the sharp-tails more so than the seasides. 



That the sharp-tails and seasides are closely related cannot be 

 questioned. Though each occupies a separate niche in the same 

 marshes as regards nesting sites and feeding habits, they share many 

 similarities in appearance, song, behavior, and food. In 1928 a male 

 seaside sparrow spent the early summer in a sharp-tail colony in 



