Olivaceous Woodcreeper
Sittasomus griseicapillus
The olivaceous woodcreeper is one of the smallest members of its subfamily. It has a slim body and a short straight bill, and unlike most other woodcreepers has no streaks or spots. The sexes' plumages are alike but females average smaller than males. Adults are 13.1 to 19.3 cm (5.2 to 7.6 in) long. Males weigh 9.0 to 18.0 g (0.32 to 0.63 oz) and females 8.6 to 16.0 g (0.30 to 0.56 oz). Length and weight vary geographically. All subspecies have a dark iris, a dark gray to black maxilla, a black to light gray mandible with a darker tip, and gray, bluish gray, or black legs and feet. Voice: The olivaceous woodcreeper's vocalizations vary widely across the subspecies. There are at least six song types and can be sorted into two groups. Subspecies in Middle America, northern South America, and west of the Andes make "a rapid staccato trill or thin rattle". Those in Amazonia and eastern and southeastern Brazil make "a rapid, alternating series of clear whistles". The song of S. g.
ID text from Wikipedia, CC BY-SA 4.0
Wedge-billed Woodcreeper
Glyphorynchus spirurus
The wedge-billed woodcreeper is the smallest woodcreeper, with a short, upturned, wedge-shaped bill resembling those of the three members of genus Xenops. It is 13 to 16 cm (5.1 to 6.3 in) long and weighs 10.5 to 21 g (0.37 to 0.74 oz). The sexes are alike. The nominate subspecies G. s. spirurus has a grayish forehead, a rich brown to russet-brown crown and nape, light buff lores, a thin buff to buff-white supercilium, a buff eyering, sooty-brown auriculars, and a brown malar stripe. Voice: The wedge-billed woodcreeper sings mostly at dusk and dawn, though occasionally during the day as well. The subspecies in the pectoralis group of Central America into Colombia sing "a rapidly ascending, accelerating and somewhat slurred series of c. 25 bubbly notes...'twee-lee-lee-le-le-ee-ee-eeeeeé' ". It is also described as "weet-weet-WEEET-WEEET-weet-peet-peeet't't't't't't'teu".
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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