Natterer's Slaty Antshrike

Natterer's slaty antshrike (''Thamnophilus stictocephalus'') is a species of bird in subfamily Thamnophilinae of family Thamnophilidae, the "typical antbirds". It is found in Bolivia and Brazil.

Taxonomy and systematics

Natterer's slaty antshrike was described by the Austrian ornithologist August von Pelzeln ''Thamnophilus stictocephalus''.

Natterer's slaty antshrike has two subspecies, the nominate ''T. s. stictocephalus'' ( Pelzeln, 1868) and ''T. s. parkeri'' (Isler, ML, Isler, PR & Whitney, 1997). The nominate subspecies previously had long been treated as a subspecies of ''T. punctatus'', which was then called the slaty antshrike. Following the results of a study published in 1997, the slaty antshrike was split into six species. One of them is Natterer's slaty antshrike; the same study determined that the former ''T. p. stictocephalus'' was actually the two subspecies that make up Natterer's. To avoid confusion the remnant ''T. punctatus'' was given its present name of northern slaty antshrike.Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, G. Del-Rio, A. Jaramillo, D. F. Lane, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. Version 4 March 2024. A classification of the bird species of South America. American Ornithological Society. https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm retrieved March 5, 2024Isler, M.L., Isler, P.R. and Whitney, B.M. (1997). "Biogeography and systematics of the ''Thamnophilus punctatus'' (Thamnophilidae) complex". Pp. 355-381 in "Studies in Neotropical Ornithology Honoring Ted Parker" (J. V. Remsen, Jr., ed.). Ornithological Monographs No. 48.

Description

Natterer's slaty antshrike is long and weighs . Members of genus ''Thamnophilus'' are largish members of the antbird family; all have stout bills with a hook like those of true shrikes. This species exhibits significant sexual dimorphism. Adult males of the nominate subspecies have a black forehead with gray spots and a black crown. Their back is mixed black and gray with a hidden white patch between their scapulars. Their face is gray. Their wings and wing coverts are black with white spots and edges. Their tail is black with white tips on the feathers. Their underparts are gray with a whitish belly. Adult females have a rufous crown and reddish yellow-brown upperparts with dark brown scapulars. Their wings are dark brown with white spots on the coverts and clay colored edges on the flight feathers. Their tail is dark brown with white tips on the feathers. Their underparts are a mix of light clay and light gray that is paler on the throat and belly. Males of subspecies ''T. s. parkeri'' have a gray forehead, a gray back with a few black spots, and paler underparts than the nominate; their belly center is white. Females have less reddish upperparts than the nominate.Zimmer, K. and M.L. Isler (2020). Natterer's Slaty-Antshrike (''Thamnophilus stictocephalus''), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.natsla1.01 retrieved March 27, 2024

Distribution and habitat

The nominate subspecies of Natterer's slaty antshrike is found in Brazil south of the Amazon between the Madeira and Tocantins rivers and southwest into Rondônia and northern and western Mato Grosso Brazilian states and northern Beni Department in extreme northern Bolivia. Subspecies ''T. s. parkeri'' is found only in the Serranía de Huanchaca in extreme northeastern Bolivia's Santa Cruz Department. The species inhabits different landscapes across its range. Along the Amazon it mostly occurs in patches of forest on white-sand soil, on the edges of humid evergreen forest, and in forest clearings such as those caused by fallen trees. At the southern end of its Brazilian range it occurs in semi-deciduous forest and gallery forest. In the Serranía de Huanchaca it occurs on the edges of evergreen forest within grasslands and ''cerrado''. In elevation it ranges from near sea level to .

Behavior

Movement

Natterer's slaty antshrike is presumed to be a year-round resident throughout its range.

Feeding

The diet of Natterer's slaty antshrike has not been detailed but includes insects and other arthropods. It usually forages singly or in pairs and is not known to join mixed-species feeding flocks. It usually forages in the understorey to mid-storey, mostly between of the ground. It hops through vegetation, gleaning prey while reaching or lunging from a perch; it also makes short upward sallies. It takes prey from leaves, branches, and vines. It occasionally follows army ant swarms in its territory.

Breeding

Nothing is known about the breeding biology of Natterer's slaty antshrike.

Vocalization

The song of Natterer's slaty antshrike is a "series of level, nasal notes, starting slowly, but accelerating to a level, bouncing rattle (3-4 sec)". Its calls include "short and long 'caw' notes" and an "abrupt growl".

Status

The IUCN has assessed Natterer's slaty antshrike as being of Least Concern. It has a large range; its population size is not known and is believed to be decreasing. No immediate threats have been identified. It is considered locally fairly common across its range and occurs in large protected areas in both countries. " bstantial populations exist within humid-forest regions that are largely intact and under no threat of development."

References

{{Taxonbar, from=Q1076020

Natterer's slaty antshrike
Birds of the Bolivian Amazon
Birds of the Brazilian Amazon
Birds of Southern Amazonia
Natterer's slaty antshrike
Taxa named by August von Pelzeln
Taxonomy articles created by Polbot