Behavior

Walking, Climbing

To move between foraging sites, the Horned Screamer wades or walks for an average of 22.0 seconds (5 Naranjo, L. G. (1986). Aspects of the biology of the Horned Screamer in southwestern Colombia. Wilson Bulletin 98(2):243–256. Close ).

Flight

Flying is rare, especially in comparison with the two other screamer species. Flights are commonly short, lasting 5 seconds on average (5 Naranjo, L. G. (1986). Aspects of the biology of the Horned Screamer in southwestern Colombia. Wilson Bulletin 98(2):243–256. Close ).

Preening

Preening is more common in the early morning, and most preening time is focused on the breast feathers (5 Naranjo, L. G. (1986). Aspects of the biology of the Horned Screamer in southwestern Colombia. Wilson Bulletin 98(2):243–256. Close ).

Sleeping

When sleeping, the bird closes its eyes and rests its bill on its retracted neck or buries it in its back feathers (5 Naranjo, L. G. (1986). Aspects of the biology of the Horned Screamer in southwestern Colombia. Wilson Bulletin 98(2):243–256. Close ).

Daily Time Budget

The most detailed description of the behavior of the Horned Screamer is by Naranjo (5 Naranjo, L. G. (1986). Aspects of the biology of the Horned Screamer in southwestern Colombia. Wilson Bulletin 98(2):243–256. Close ), the primary source for the following summary:

A Horned Screamer's time is mainly spent standing, sleeping, preening, and foraging. Standing is the most common behavior, especially as the day progresses. In a typical posture, the bird stands with its neck partially retracted, wings folded, and sometimes with one leg raised (5 Naranjo, L. G. (1986). Aspects of the biology of the Horned Screamer in southwestern Colombia. Wilson Bulletin 98(2):243–256. Close ).

Other behaviors are associated with standing and preening, such as wing-shake, head-shake, and tail-wag. Between bouts of standing and preening, the Horned Screamer also performs a jaw-stretch, wing-and-leg-stretch, and both-wings-stretch (5 Naranjo, L. G. (1986). Aspects of the biology of the Horned Screamer in southwestern Colombia. Wilson Bulletin 98(2):243–256. Close ).

No information available.

Mating System and Operational Sex Ratio

he Horned Screamer is a monogamous species (5 Naranjo, L. G. (1986). Aspects of the biology of the Horned Screamer in southwestern Colombia. Wilson Bulletin 98(2):243–256. Close ).

Courtship, Copulation, and Pair Bond

The Horned Screamer has a courtship display, unlike other screamer species (Southern Screamer (Chauna torquata), Northern Screamer (Chauna chavaria)). Before copulation, the male walks around a standing female with his bill pointing downward, neck retracted, dorsal feathers partially erected, and wings partially opened with the carpal joint facing towards the floor. After circling 1-3 times, the male bows in front of the female (5 Naranjo, L. G. (1986). Aspects of the biology of the Horned Screamer in southwestern Colombia. Wilson Bulletin 98(2):243–256. Close ). Occasionally, there will also be head-flicking (59 Barrow, J.H., Black, J.M. and Walter, W.B. (1986). Behaviour patterns and their function in the Horned Screamer. Wildfowl 37: 156-162. Close , 5 Naranjo, L. G. (1986). Aspects of the biology of the Horned Screamer in southwestern Colombia. Wilson Bulletin 98(2):243–256. Close ).

Pair-bonding behaviors includes allopreening, calling, head-arching, and mock-preening (5 Naranjo, L. G. (1986). Aspects of the biology of the Horned Screamer in southwestern Colombia. Wilson Bulletin 98(2):243–256. Close , 60 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ). In Naranjo's study, these bonds were stable, but there was one instance of a juvenile male courting an adult female that ended in aggression. The male adult male and the juvenile became engaged in a fight that involved carpal spurs, crop inflation, and neck grappling. After 40 seconds, the adult male left the site and the juvenile and adult female vocalized in duet form (5 Naranjo, L. G. (1986). Aspects of the biology of the Horned Screamer in southwestern Colombia. Wilson Bulletin 98(2):243–256. Close ).

Degree of Sociality

Frequently observed in pairs; sometimes in groups of up to six birds, although solitary individuals are also common (36 Gill, F. B., F. J. Stokes, and C. C. Stokes (1974). Observations on the Horned Screamer. Wilson Bulletin 86(1):43–50. Close , 5 Naranjo, L. G. (1986). Aspects of the biology of the Horned Screamer in southwestern Colombia. Wilson Bulletin 98(2):243–256. Close ). Within a group, birds will engage in social-preening and head-bobbing (5 Naranjo, L. G. (1986). Aspects of the biology of the Horned Screamer in southwestern Colombia. Wilson Bulletin 98(2):243–256. Close ), and groups may call to one another (36 Gill, F. B., F. J. Stokes, and C. C. Stokes (1974). Observations on the Horned Screamer. Wilson Bulletin 86(1):43–50. Close ).

Nonpredatory Interspecific Interactions

Horned Screamer has been reported to interact with Southern Lapwing (Vanellus chilensis), which sometimes mobs the screamer. Naranjo reported that if a Southern Lapwing in flight came near a standing screamer, the screamer stretched its neck in an alarm posture, then bowed and called (5 Naranjo, L. G. (1986). Aspects of the biology of the Horned Screamer in southwestern Colombia. Wilson Bulletin 98(2):243–256. Close ).

No information regarding natural predation; however, the eggs of screamers are consumed in human households in the Amazon (61 Gonzalez, J. A. (1999). Effects of harvesting of waterbirds and their eggs by native people in the northeastern Peruvian Amazon. Waterbirds 22 (2):217-224. Close ).