Table 2. Behavioural ethogram of the study.

The behaviour list has been prepared based on preliminary observation of the flock and on previous studies on the Northern bald ibis as well as on relative species (Hirsch, 1979; Kopij, 1998; Pegoraro & Föger, 2001; Mark, 2007; Vargas-Ashby & Pankhurst, 2007; Clark et al., 2012; Fernández-Juricic, 2012; Moulton et al., 2013; Frigerio et al., 2016).

Individual behaviour
	Alertness	Moving the head, stretching the neck listening or watching something in the surrounding.
	Attentive behaviour	Being vigilant, scanning the environment.
	Comfort behaviour	Tidying and cleaning the own feathers with the bill, scratching, bathing and sunbathing (fanning the wings to warm up in the sun).
	Exploration	Looking for food probing the ground, tree branches, crevices and other elements of the aviary with the bill.
	Flight	Flying or hopping from one point to the other of the enclosure.
	Walking	Walking around the aviary.
	Maintenance	Eating the food provided in the feeding point, defecating, drinking.
	Manipulation/play	Manipulating food, objects, twigs, rocks or other inanimate items found in the aviary using the bill or the legs.
	Resting	Standing on one or both legs, with the head turned back and tucked beneath the wings.
Social behaviour
	Social affiliative behaviour
	Preening	Tidying and cleaning the feathers of a conspecific with the bill.
	Other affiliative	Greeting displays including head tossing, head rubbing, mutual bill shaking; observing conspecifics.
	Social agonistic behaviour
	Aggression	Pecking towards approaching birds, hitting a conspecific with the bill or with the legs.
	Agonistic display	Bill gaping, ruffling the helmsman feathers, moving or lunging toward conspecifics, touching slightly with the tip of the bill. Anti-predatory behaviour (e.g.: mobbing).
Not visible
	Out of sight	The ibis spends time “out of sight” and it is not possible to see what the individual is doing. In particular, the bird is in sheltered areas such as nest boxes, rock crevices or behind trees and bushes.