Paul A Schwartz
14 Jul 1966
- Rio Grande; km 10; El Palmar
- 7.9666667 -61.8833333
- 250 meters
- NAGRA III
- Electro-Voice 650
- Parabola 91.4cm (36in)
NOTES: Neotropical Institute Cut # 16. Bulk reel: 21; Extra cut length: 9:45 part B; Extra cut(s) on bulk reel: 22; Extra cut length: 11:23 part C; Extra cut length: 10:32 part D; Extra cut length: 10:47 part E
Time: 0445 hr, then 0505hr to 0520hr. These are no doubt same birds as in Cut #1). They are now closer (they had been singing at least as early as 0400hr). First is a high-voiced bird in focus. Now hear a low-voiced bird too. Then a second high-voiced bird starts to sing too. These songs are all mostly eight- or nine-note phrases. Then the low-voiced bird stops singing. Quality: 2 (background noise). Level: +5.
The low-voiced bird starts to sing again [at 0520hr]. The two high-voiced birds have continued all the while. Quality: 1-2 (after songs stop). Level: +5.
Then, what seems from the relative loudness to be a second low-voiced bird starts to sing a "dawn song" that apears to be fairly typical of M. semitorquatus. Whether it is really a different bird or not, I can't be sure for during this time the "other" low-voiced bird stops singing, as does the background high-voiced bird. After the "dawn song" stops, the "other" low-voiced bird starts to sing again (also the background high-voiced bird) and again this sounds louder, seeming to confirm that it's a different bird.
Then a bird starts to sing the "dawn song" again but I don't know if it's the same as sang the dawn song before. This recording is "focused" on this bird. Its voice sounds higher than the other "dawn song" but this may be due to parabola effect. The nearer high-voiced bird continues to sing, as it did during the other "dawn song."
Then after I moved a bit closer I focus on one of the high-voiced birds and the other high-voiced and the low-voiced are in background.
Then I moved still closer. Relative "focus" approximately same.
0550hr, cloudy fair.
Then I changed position again and am now focused on the low-voiced bird. This is still all natural song; there has been no playback. (All mostly seven- to nine-note phrases.)
The two high-voiced birds were seen and both are in juvenal or sub-adult plumage. One was collected (female juv. #5225). The other seemed a bit larger and was much more rufous all over than the one collected. The low-voiced bird could never be seen.
Voice note @ end about [paragraph above] and playback tried.