This secretive forest-inhabiting hawk is mostly seen either flying or sitting at low heights.

- Uncommon to scarce forest resident (Global Raptor Information Network 2011).

- One of the sympatric Accipiter species which are widespread in the Lower Guinea forest block (Louette & Herroelen 2007).

West and Central Africa: from Nigeria to the Congo River basin (Kemp 1994).

Simulated distribution for the present (based on recent observed climate change), for 2025, 2055 and 2085 (based on projected future climate change) is available (BirdLife International and Durham University 2011) at: http://www.birdlife.org/datazone/speciesfactsheet.php?id=3424&m=2

Identification features (Louette 2010):

- Adult:

Upperparts: blackish

Throat: white, finely streaked

Breast and belly: dirty white with bold blackish-brown bars (sometimes with chestnut traces)

Flanks: chestnut

Thighs: plain chestnut

Tail: blackish with 3-4 relatively large spots

Irides: usually red

Legs and feet: bright yellow with black cast

- Immature:

Upperparts: dark brown

Throat: white with central streak

Breast: heavily spotted

Belly: white with a variable amount of spots

Flanks: heavily streaked or barred

Thighs: barred with wider bars than toussenelii paraspecies

Legs and feet: yellow with black cast

c. 30-35 cm (Kemp 1994).

Medium-sized, among the Central African forest-inhabiting hawks (Louette & Herroelen 2007).

Saturated colours and heavy grey and brown barring below distinctive; A. castanilius is smaller, but longer-tailed than A. toussenelii (Kemp 1994).

Apparently fairly close to A. toussenelii and A. tachiro, but distinguished by smaller size and long inner claw (Kemp 1994).

• Terrestrial
• Freshwater

Lowland tropical evergreen forest, sometimes extending into dense adjacent secondary growth (Kemp 1994) or even into plantations (Global Raptor Information Network 2011).

Adaptation to a life in dense forest or darker environment is suggested by its relatively large eyes and its proportionally broader skull in comparison with the African Goshawk population Accipiter tachiro/toussenelii (Louette& Herroelen 2007).

Probably resident and sedentary (Kemp 1994).

Non-migratory, but juveniles disperse from breeding areas (Bildstein 2006 in Global Raptor Information Network 2011).

It feeds on small vertebrates, including birds, reptiles, amphibians and mammals (Brosset 1973 in Global Raptor Information Network 2011), and invertebrates, such as grasshoppers and beetles (Louette and Herroelen 2007).

The global population size has not been quantified, but the species is described as common in larger tracts of forest (del Hoyo et al. 1992 in BirdLife International 2011).

Sitting on posts a few metres high repeatedly during consecutive days: regularly observed flying fast and low, e.g. over road, dyke, often in or near village (hunting chickens; entered house) and in plantations or secondary vegetation; observed hunting insects in trees; quite vocal (Louette & Herroelen 2007).

Herroelen (2006) stated that the main breeding period for this species in the Democratic Republic of Congo is January-April. The breeding period in Gabon is also reported as January to April (Ferguson-Lees and Christie 2001 in Global Raptor Information Network 2011).

A. castanilius does not belong to the African Goshawk group but is the most closely related sister species of the African Goshawk group tachiro/toussenelii (Jordaens et al. 2011, in prep.).

IUCN Red List Status: Least Concern (LC)

The population is suspected to be in decline owing to ongoing habitat destruction (Ferguson-Lees and Christie 2001 in BirdLife International 2011).