Nestling vocalization development in the European Starling (Sturnus vulgaris)

Abstract

Nestlings vocalize while begging to elicit food from parents, and although many studies examine their begging behaviour, surprisingly little is known about vocal development in nestling passerines. European Starlings (Sturnus vulgaris) are a cavity-nesting passerine commonly found in anthropogenic environments. Adult males are open-ended learners, increasing the complexity of their songs with age. The objective of my study was to determine the ontogeny of vocalizations in nestling European Starlings over the nestling period (0 to ~22 days old). Using spectrograms, I observed and catalogued their calls every four days during the period between hatching and fledging. I found that the largest variation in vocalizations occurred when the nestlings were 5 to 13 days of age, and not when they were older. Nestlings appear to have increased consistency in their vocalizations as they grow older and settle in to their voices. It was predicted that a larger variation in call types would occur in larger brood sizes, however it was determined that there was no correlation between brood size and number of call types.