Signalling of Nutritional Need by Magpie Nestlings

The relationship between begging behaviour, chick nutritional state, and parental distribution of food within broods was studied in 4‐ and 5‐chick magpie Pica pica broods under natural conditions. Three components of the begging display (duration, latency, and posture) were highly correlated with each other and also with the emission and duration of begging calls. Begging performance was strongly influenced by the food intake of nestlings during...