The Red-necked Falcon, a medium-sized raptor, boasts a striking rufous crown and nape, contrasting with its bluish-grey wings and upper body. The bird's tail features narrow bars and a distinctive broad subterminal black band tipped with white. The legs, ceres, and eyering are a vibrant yellow, while the bill's tip is black and the base a greenish yellow. The species exhibits sexual dimorphism, with females being larger than males.
Adults have a wingspan of approximately 85 cm and measure 30–36 cm in length. The wingtip does not extend to the tail tip when at rest. The second and third primaries are nearly equal in length, with the first being significantly shorter. The species' call is a piercing ki-ki-ki-ki, and juveniles can be identified by their buff underparts and less pronounced barring.
In Africa, the Red-necked Falcon inhabits semi-desert, savannah, and other dry open areas with sparse trees, including riverine forests. It is often seen perched atop Borassus palms, which are also used for breeding. In India, the species favors open habitats and avoids dense forests and high elevations.
The Red-necked Falcon has two distinct populations: one in India and another in sub-Saharan Africa. The Indian subspecies was historically found as far west as southeastern Iran, while the African subspecies is sometimes considered a separate species due to its unique geographic range and pattern.
These falcons hunt primarily at dawn and dusk, often in pairs. They employ a unique hunting strategy where one bird flushes out prey by flying low, while the other captures the startled prey from above. They are known to feed on a variety of birds, bats, and squirrels.
The Red-necked Falcon's vocalization is characterized by a shrill ki-ki-ki-ki.
Breeding seasons vary by region, with January to March in India and beginning in August in Zambia. Courtship feeding is a unique behavior where the female feeds the male. They typically reuse old nests of corvids or build their own in tree forks or palm crowns. The female incubates the eggs, which hatch after about 32 to 34 days.
The African subspecies, sometimes considered a separate species, has a white face with black moustachial stripes and a rufous foreneck band, distinguishing it from the Indian form.
The Red-necked Falcon preys on open-area birds, bats, and occasionally small mammals and large insects. They have been observed caching prey for later consumption.
The Red-necked Falcon is currently listed as Near Threatened on the IUCN Red List, indicating that it faces threats that could lead to its vulnerability in the near future.
Historically, the Red-necked Falcon was a favored bird among Indian falconers, particularly for hunting the Indian roller due to the engaging aerial chases it would provoke.
Captive Red-necked Falcons can be susceptible to Newcastle disease virus and various parasites, including Trichomonas and nematodes like Cyrnea eurycerca.