18 



NORTH AMERICAN FAUNA 67 



Parish, in the subdelta marsh, in December 1952. Cut Off is approxi- 

 mately 25 miles south of New Orleans. King Rails were collected at 

 Chenier au Tigre, January 1, 3, and 5, 1934, by A. M. Bailey (Ober- 

 holser 1938, p. 199) ; at the same location on March 31 and April 1, 

 1947, by I. N. Gabrielson; and at Avery Island, May 7, 11, 13, and 15, 

 1930, by E. G. Wright (Oberholser, 1938, p. 199). 



I made a census, based on calls, in Terrebonne Parish, 1.2 miles south 

 of Dulac, on January 3, 1963, to determine the abundance of King 

 Rails in the area (table 3). The birds were heard calling from what 

 appeared to be an abandoned silted-in canal where shallow ponds were 

 interspersed with dense patches of vegetation dominated by clump 

 grass {Spartina spartinae) . In a 1-mile strip, 50 feet wide, 19 King 

 Rails were counted. Short-billed Marsh Wrens {Cistothoru^ platensis) , 

 Soras, Virginia Rails, and Common Gallinules {Gallinula chloropus) 

 were also common in this same census strip. 



The prairie marshes 



The prairie marshes in the southwestern part of the Louisiana gulf 

 coast (Vermilion and Cameron Parishes) comprise 19 percent of the 

 total area. Near the gulf coast much of the prairie marsh is bisected 

 by ridges known as cheniers (stranded rims of the sea or old shore- 

 line) that parallel the coEist (fig. 5). Cheniers extend in straight 

 lines for many miles and in most places are wide enough only for a 



Figure 5. — Prairie marsh, Grand Chenier, La., March 1956. Mixed King and 

 Clapper Rail populations sometimes occur in the same marsh type in this area. 

 Both species were collected from the same half -a ere pool near here, April 1956. 



