1909] Beebe: Ecology of the Hoatzin. 55 



is usually heard when they are disturbed, and it is one of which 

 it is not easy to give an exact idea. It recalls slightly the shrill 

 screech of the guinea-bird, (Numida) , but it is made up of dis- 

 jointed utterances, like the notes heigh or sheigh (ei as in 

 sleigh), pronounced with a peculiarly sharp and shrill intona- 

 tion, so as to be quite hiss-like." The reckless way of thrashing 

 through the undergrowth, and the apparent looseness of wing 

 and tail and general carelessness of plumage bring to mind the 

 crazy antics of anis, a fact not wholly uninteresting when we re- 

 call certain hints of cuculine structure in the Hoatzin. 



Except during the extreme heat of mid-day, the Hoatzins 

 prefer conspicuous positions overhanging the water on man- 

 groves or other trees, among the foliage of which they roost at 

 night. They appear to be extremely sedentary, and day after 

 day we could be sure of finding the birds in the same place. We 

 located nine flocks, ranging from a single pair to forty-two birds 

 in number, and these seemed never to move from their favorite 

 trees except when driven back a few yards into the jungle by our 

 intruding canoe. 



In these same trees over the water w^e found remains of 

 many nests, in various stages of disintegration. As the number 

 of the nests bore a fairly accurate relation to the pairs of birds, 

 and as we saw these large, rough platforms of sticks at no other 

 points, circumstantial evidence would indicate that the sedentary 

 life of these Hoatzins is seasonal, if not, indeed, annual. We 

 were told that they nest in May and June in this locality. 



After they flop and clamber a few yards away from the 

 canoe, they all quiet down and with waving crests, crane their 

 necks at us in curiosity from their perches. Each time tljey 

 utter their grating note, they raise the tail and wings, spreading 

 both widely. 



We had no opportunity of observing the quadrupedal habits 

 of the young Hoatzins, but an interesting observation, first 

 noted by Mrs. Beebe, was that this finger or hand-like use of the 

 wing is present in the adults as well. They never fly if they can 

 help it, and even when they pass over firm ground seem never to 

 descend to it. But their method of arboreal locomotion is to 

 push and flop from branch to branch. When the foliage and 

 hanging vines are very thick, they use their wings, either to- 

 gether or alternately, to push aside the obstruction and to keep 

 themselves from falling, until a firm grip has been obtained with 

 the toes. This habit is extremely wearing on the primary feath- 

 ers which become much frayed from friction against stems and 

 branches. 



