NOTES ON HOATZINS 163 



had intentions on her nest she returned and perched fifteen 

 or twenty feet away, croaking continually, her mate a few 

 feet farther off, and all the hoatzins within sight or hearing 

 joining in sympathetic disharmony, all with synchronous 

 lifting of tail and wings at each utterance. The voice of 

 the female was appreciably deeper than that of the male, 

 having more of a gurgling character, like one of the notes of 

 a curassow. The usual note of both sexes is an unwritable, 

 hoarse, creaking sound, quite cicada or frog-like. Their 

 tameness was astounding, and they would often sit un- 

 moved, while we were walking noisily about or focussing the 

 camera within two yards. If several were sitting on a 

 branch and one was shot, the others would often show no 

 symptoms of concern or alarm, either at the noise of the gun 

 or the fall of their companion. A bird which may have been 

 crouched close to the slain bird would continue to preen its 

 plumage without a glance downward. When the young have 

 attained their first full plumage it was almost impossible to 

 distinguish them from the older members of the flock except 

 by their generally smaller size. 



But the heart of our interest in the hoatzins centered in 

 the nestlings. Some kind Providence directed the time of 

 our visit, which I choose against the advice of some of the 

 very earliest inhabitants of New Amsterdam. It turned out 

 that we were on the scene exactly at the right time. A week 

 either way would have yielded much poorer results. The 

 nestlings in seven occupied nests, observed as we drifted 

 along shore, or landed and climbed among the thorns, were 

 in an almost identical stage of development. In fact the 

 greatest difference in size occurred between two nestlings 

 of the same brood. Their down was a thin, scanty, fuzzy 

 covering, and the flight feathers were less than a half inch 

 in length. No age would have showed to better advantage 

 every movement of wings or head. 



When a mother hoatzin took reluctant flight from her 

 nest, the young bird at once stood upright and looked curi- 



