ML447108701

Age and sex

Adult Male - 1

Media notes

While we were descending the slope, the pair of gnatcatchers kept in front of us, perching on different types of vegetation, including this cactus.

Observation details

Gustavo's comments: Pair(s). Heard(s) and seen. Subspecies and/or taxon identified by size, shape, color pattern and/or sound. Male had a complete solid black cap surrounding the ear patch giving the cap a pointy claw-shape look to the corners at the sides of the neck, slaty back, whitish below, with grayish chest sides, black wings with inner white-webbed flight feathers, black short pointy bill and black tail with prominent white outer tail feathers. Female quite similar to male in overall plumage except by the narrow somewhat broken white spectacles (just to over the eye) joining with whitish lores and supraloral stripe. The bird was first heard at the higher parts of the scrubby slope, later on after use of PB, birds responded immediately and came quite close on exposed branches to investigate, and then both began foraging nearby on small bushes on lower part of the slope, making contact calls. Habitat: Pacific arid scrub with scattered cactus. Bird heard first at ca. 09:40hrs. and pair last heard and seen by 10:45hrs. Elevation ca. 2300 m. Audio recorded. (recordings after PB, and natural vocalizations). *Literature ("All the Birds of the World" book published by Lynx Edicions - Josep del Hoyo (Editor) and "Birds of Peru" book (Revised and Updated Edition) published by Princeton Field Guides - Thomas S. Schulenberg et. al. (Author)) show that female of Polioptila maior has a white narrow forehead which joins with white broken spectacles, which is the only noticeable difference with the female shown in the picture(s) taken by some members in the group, where the female has black forehead concolor with cap. This difference rise questions: Maybe a different subspecies isolated by geographic barriers or a hybrid between 2 taxa?. Added by me: We saw two birds moving actively through the bushes, staying more or less together. It was obvious that they were Polioptila (small size, gray upperparts with black cap, white underparts, straight, thin bill). One of them had a complete black cap that extended to the eyes on the sides and reached to the bill on the front, corresponding to a male P. plumbea maior and different from P. bileanata bilieanata. The other bird had dirty white lores, some dirty white above the bill and a faint dirty white eyebrow that hardly extended behind the eye. We supposed this was the female, mainly because the two birds moved around as a pair, but the pattern does not closely correspond to the female maior as depicted in Birds of Peru by Schulenberg et al. Superficially, the female looked like a male with some imperfections in its plumage. The birds were vocalizing regularly and we heard both the monotone, slightly descending, buzzy calls and the more elaborate song, all recorded by Gustavo and included in the eBird checklist. I have seen the species only once before in Gotas de Agua, Cajamarca (and P. bilieanata a handful of times in Lambayeque). As member of the CRALEC, I have been investigating the occurence of P. plumbea and P. bilieanata in the department of Lima and had several discussions about the species. The only possible confusion would be with P. bilieanata, for which the male does not have a complete black cap, while the female's cap is gray, not black. P. bilieanata is only expected at lower altitudes. I distinguished it from bilieanata by appearance, not by song, although I know there is a difference. Our main target for this visit was White-throated Earthcreeper, but we knew that Tropical Gnatcatcher has been observed before at this location, eleven years ago. We did look out for the species, but I considered it unlikely that we would find it. After observing the earthcreeper everybody except Gustavo walked back to the car. Gustavo stayed on the slope to make some sound recordings. It was at that moment that he heard the calls. After a while, he came down to tell us and we walked back up together, after which Gustavo and David quickly located the species halfway up the slope. The conditions for taking photos were very difficult, because of the harsh light conditions, the very steep slope without any path and the continuous activity of the birds. We spent a good time watching them and taking photos right on the slope. When we slowly started walking down, the birds were moving in front of us, perching on different bushes and cactuses, but never staying for more than a few seconds at the same location. The kept moving in front of us until will we has almost reached the dirt road. Between the first and the last observation, an hour had past.

Technical information

Model

COOLPIX P1000

ISO

100

Focal length

38.6 mm

Flash

Flash did not fire

f-stop

f/4.5

Shutter speed

1/1000 sec

Dimensions

912 pixels x 683 pixels

Original file size

381.24 KB