ML112779241

Age

Not specified

Sex

Not specified

Observation details

*Inside large area of bamboo at the end of 10; the exact spot was the last major opening in the canopy before ascending the slope towards 25. One gnatwren heard singing spontaneously as I approached. After playback of R. m. obscurus, it became quiet for a minute as it approached and then started singing loudly from ~10 m. At both of these times, the bird was giving 'typical' multi-part chattering ssp. songs. After recording this individual for a couple minutes and letting it move away, I started playback of R. m. amazonum ('trilling gnatwren'), and the same individual came back in, singing and acting much more aggressively than before, while a second bird started vocalizing with an even-pitched trill. I eventually got photos of this second bird, which I originally thought appeared to be a phenotypic R. m. obscurus 'chattering gnatwren' due to the two small white spots on the underside of the retrices, which matched descriptions of that form, but apparently look better for R. m. amazonum (obscurus would have much larger white spots). The trill was shorter and of a different tone than my ssp. amazonum playback, sounding more nasal and with more separation between notes than the higher, more musical trill of that subspecies in my playback.

Technical information

Model

Canon EOS 7D

Lens

EF400mm f/5.6L USM

ISO

6400

Focal length

400 mm

Flash

Flash did not fire, auto

f-stop

f/5.6

Shutter speed

1/1000 sec

Dimensions

3083 pixels x 2029 pixels

Original file size

2.02 MB