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76

Rhamphocelus, Jun. 15, 1961, VII       

his attack and escape drives are also very high.

[[red pencil]] II. [[red pencil]] The male assumes the elaborate Pre-Cop Posture, with Wass, etc. Then either flies straight on to the back of the female (if he is right beside her when he assumes the Pre-Cop Posture), or (if he has assumed the Pre-Cop Posture some distance away from the female) sidles toward her, without Pivoting, and then mounts.

This presumably occurs when his sex drive is high but his attack and escape drives are weaker than in I above. 

[[red pencil]] III. [[red pencil]] The male mounts the female without preliminary display. This presumably occurs when his hostility is relatively even weaker than in II above.


Rhamphocelus, I.   
            
June 16, 1961
Barro Colorado

Arrive by cage of Sangres 5:50 a.m.

One bird, presumably the male, does some "Keeyoo" singing while it is still dark. While sitting quietly, quite far away from its mate.

"Keeyoo" songs sometimes interrupted by single PCN's, or peculiar single "Kraa" or "Krauh" notes. I think that both these latter must be variants of ACN's.

It is interesting that this bird should do "Keeyoo" singing this morning. The male certainly did not sing yesterday while he was alone, before I caught him.

Getting light now 6:03 a.m.

Yes! It is definitely the male who is singing "Keeyoo"s now. Doing so while the female sings quietly only 1-1/2 ft away!