NATURAL HISTORY OF THE KING RAIL 



45 



The most unusual plumage that I have seen was that of a very dark 

 brown, almost blackish bird near Lake Okeechobee, Fla., January 1958. 

 William B. Robertson (personal communication) told me of seeing 

 several birds with similar dark plumage in the Everglades, and Luther 

 C. Goldman collected such a specimen near Cape Sable, Fla. Dr. Harry 

 C. Oberholser examined the specimen and remarked that it had a most 

 unusual plumage. Apparently he did not make a critical study of it, 

 and it has since been lost. 



LEGS AND FEET 



Legs and feet are pale brownish gray. An adult male collected at 

 Welch, La., January 12, 1963, and two adult males collected in August 

 1963, in Delaware, had a pinkish-brown color on the inside and out- 

 side heel areas and immediately above. This heel color is apparently 

 typical of birds in their second year or older. 



BILL 



In most adult birds the bill is orange-yellow from the base to at 

 least the nares in the upper mandible, and usually slightly beyond in 

 the lower mandible. The outer part of the bill is brownish. However, 

 one marked wild bird known to be at least 2 years old had a lightish- 

 brown bill more typical of immatures. A captive immature did not 

 attiain the color at the base of the bill until it was 10 months old. The 

 color was then yollowish rather than orange-yellow. Young wild birds 

 2 to 3 months of age had lightish brown bills. The upper mandibles 

 of these birds were darker. 



TONGUE AND LINING OF MOUTH 



Tongues and mouth linings of birds 1 year or older, examined 

 immediately after collection, were a bright orange-red. Young birds 

 in juvenal plumage, collected during the summer, had yellow tongues 

 and mouth linings. 



EYE 



Irides of adult King Rails are reddish-orange while pupils are gray- 

 ish-black. Eyes of newly hatched chicks are grayish-brown, and 1- and 

 2-month-old birds have dull-brown irides. 



NOTES ON SEXING AND AGING 



In a 50-bird sample from Louisiana, examined 3 months after col- 

 lection in late fall, I was able to sex 47 of 50 birds by weight, and age 

 36 of 45 by color of the bill and heel. As an aging criterion, the color 

 of the bill is used most accurately with live or freshly killed birds, 

 because with time it fades. Wing measurements can also be used as 

 an aid in sexing birds, since the average for males is nearly 10 milli- 



