Buff-necked Ibis

Scientific Name: Theristicus caudatus

Classification: Order: Pelecaniformes; Family: Threskiornithidae

Buff-necked Ibis

Brief Description

A large, terrestrial ibis with a distinct orange-buff neck, a long downward-curved black bill, and pink legs. It is often seen walking in open fields and wetlands.

Additional Information

  • Region of Origin: South America, broadly distributed across northern and central South America and the Southern Cone, excluding the Andes and the Amazon rainforest interior.
  • Typical Sighting Period: Year-round in most of its range, as it is largely non-migratory.
  • Plumage Details: Features a buff/cream neck and breast, with dark grey to black wings and underparts. The crown is rufous-brown. It lacks significant sexual dimorphism, though juveniles may appear duller with more streaking on the neck.
  • Ecological Significance: Acts as an important predator of terrestrial invertebrates and small vertebrates, helping to control insect and rodent populations in grassland ecosystems.
  • Conservation Status: Least Concern (IUCN); Population is stable and the species is relatively common in its range.
  • Observation Tips: Look for them in open pastures, grasslands, and marshes. They are often vocal and easily identified by their loud, metallic, trumpeting calls, especially at dawn and dusk.

Size & Weight

Length: 71-76 cm (28-30 in); Weight: approximately 1.1-1.4 kg.

Diet

Opportunistic carnivore; eats insects, spiders, frogs, lizards, snakes, and occasionally small rodents. It probes the soil or grass with its long bill.

Habitat

Open grasslands, savanna, marshes, pastures, and sometimes agricultural fields or suburban lawns.

Migration

Resident or sedentary; some populations may undertake local movements in response to water availability or rainfall patterns.

Voice (Call & Song)

A loud, piercing, metallic series of honks or 'klee-klee-klee' sounds, often delivered in flight or from a perch.

Nesting & Breeding

Typically nests in colonies. Nests are platforms of sticks built in trees or on cliffs. They seasonal breeders, laying 2-4 eggs per clutch.

Key Field Marks

Buff-colored neck, rufous crown, large dark wings with white patches visible in flight, long curved bill, and bright pinkish-red legs.

Similar Species

Black-faced Ibis (Theristicus melanopis) is similar but has a black face, a darker grey body, and is generally found in more southern or high-altitude regions.

Interesting Facts

Unlike many other ibis species, the Buff-necked Ibis is highly terrestrial and is often found far from standing water. Its genus name, Theristicus, comes from the Greek word for 'harvester'.