38 BULLETIN 16 7, UNITED STATES NATIONAL MUSEUM 



(3) Fresh meat, placed on canvas covering carrion, was devoured 

 by vultures standing on the canvas, but they did not detect the 

 carrion. 



(4) A blinded black vulture did not notice carrion placed within 

 an inch of its nostrils. 



A few observers since Audubon occasionally have tested the sense 

 of smell in black vultures, but their findings are generally not con- 

 clusive, are not free from the possibility of error, and are often con- 

 tradictory. Thus, C. J. Pennock writes to me that in Florida 

 he placed "the offal from a large green turtle on the ground 15 or 

 20 yards within a grove of closely growing pine trees, averaging 

 perhaps 50 feet in height and with tops thickly interlocked but with 

 no side limbs for 30 feet up. At 8 : 15 a. m. the meal was ready ; at 

 9 o'clock a single black vulture was atop the fence nearby ; at 9 : 40 

 there were 40 birds, all black vultures sitting on the ground, perched 

 in trees or regaling themselves. No vultures were in sight when the 

 table was spread, and it was thought the repast could not be seen by 

 a flying bird at the nearest open side of the grove, but of this there 

 is a possible doubt." 



Dr. Frank M. Chapman (1929) at Barro Colorado Island has made 

 the latest and most careful experiments. Most of them were on the 

 turkey buzzard, and he says that "some of my results leave no room 

 for doubt that the turkey buzzard has a highly developed sense of 

 smell. From others, exactly the opposite conclusion may be drawn." 

 On one occasion two black vultures perched on a tree about 125 feet 

 to leeward of a small house where carrion was concealed. These 

 were the first black vultures he had seen alight on the island. 



There is one source of error that so far as I know has not been 

 considered in these experiments and may account for some of the 

 contradictory results. This was brought out by Darlington (1930), 

 who in collecting beetles by the use of carrion bait in tropical 

 regions also attracted vultures, and was led to the following con- 

 clusions : 



Soon after the death of an animal, except in unusual cases or during 

 cold weather, the body attracts numbers of flies and beetles, some of which 

 may continue to circle about it for several hours or days. The resulting 

 congregation of insects is noisy and conspicuous, and of a sort which does not 

 occur except about decaying material, so that it may be considered more or 

 less characteristic of the latter. Since Vultures can undoubtedly see and per- 

 haps hear such insect swarms at a distance, they have probably learned to 

 recognize their significance, just as we recognize the significance of gatherings 

 of the Cathartidae. 



Aretas A. Saunders (1906) found that the lives of black vultures 

 on a rubber plantation in Nicaragua followed a regular routine, in- 

 fluenced only by hatching and the character of the weather. Early 



