Slaty Elaenia Elaenia strepera Scientific name definitions

The Elaenias are known for their dull and greenish plumages, often species are quite difficult to separate visually. The Slaty Elaenia is an entirely different story, it is the only species in the genus where the plumage is actually rather distinctive in the field. It is also well named; the males of this species are indeed slaty. This is another interesting aspect of this elaenia, females are much more olive above and yellower below, making it the only one in the genus that is noticeably sexually dichromatic. Also unique is the voice of this Elaenia, it is a very harsh, unpleasant chatter that stutters at first and finishes in a louder, and longer nasal chattering note. The overall sound is more likely to be considered that of a large orthopteran, or perhaps a frog rather than a bird. Slaty Elaenias breed in Yungas Forests of S Bolivia and NW Argentina, they are fond of forest edge and tend to forage in the mid story taking elevations between 500 and 2000m. However, they are highly migratory and make their way north along the Andes to Venezuela in the non-breeding season. Here they are found in lower elevations, usually as high as 500 m, but no higher. Although well known from the breeding and wintering areas, next to nothing is known about its migration and there are very few records in intervening areas.

15·5 cm; 18–20 g. Small elaenia with grey plumage, rounded head only slightly crested, tail comparatively long. Male has slate-grey head, slightly paler on cheek, white coronal patch (semi-concealed), narrow white eyering; upperparts slate-grey, wings darker dusky grey, slightly paler edgings on wing-coverts (only indistinct wingbars) and remiges; tail dusky; paler below, throat whitish to pale grey, breast and flanks grey, belly and undertail-coverts whitish; iris dark brown; bill flat and wide, black, basal half of lower mandible dull orangish; legs black. Female resembles male, but with olive wash above, more prominent wingbars tinged ochraceous, throat and breast olive-grey, contrasting with yellowish-white belly. Immature is similar to female, but with 3–4 ochraceous wingbars, paler below.

Insects, also berries. Generally inconspicuous, often remains in dense foliage, although sometimes sits erect and quietly on open branches for longish periods; often jerks tail. Usually solitary or in pairs; during migration often joins mixed-species flocks in canopy of primary forest. Perch-gleans and hover-gleans; also takes aerial insects by sallying from open perches, then reminiscent of a swallow (Hirundinidae).

Distinctive call a dry, gravelly “eh-eh-ehhhhhh” , unlike that of congeners, more like a frog or locust (Orthoptera) than a bird; silent on passage and in non-breeding quarters.