Whisper Song in the Grey Thrush Turdus cardis Immediately Before and After Feeding Their Young

Abstract

Abstract. Many bird species utter a "whisper song" at the nest site, e.g., during nest relief. However, studies on the song and its function tend to be wholly descriptive, and very few quantitative analyses have been conducted. The male Grey Thrush Turdus cardis emits the whisper whistle song immediately before and after feeding his young. In this study, the male's behavior was examined in relation to the female's presence, for four nests. The male sang on 59.5% of the occasions immediately before arrival at the nest, and on 44.6% of the occasions immediately after departure. In most males, the frequency of singing before arrival did not relate to the presence of the female at the nest. However, on occasions when the male sang before arrival, the female tended to fly away before the male's arrival, suggesting that the song was used as a sign of nest relief. The male tended to sing immediately after departure more frequently when the female was absent from the nest than when she was present, although the singing did not a#ect the timing of the female's next arrival. According to observations made immediately before fledging, nestling activity was synchronized with the frequency of the male's singing behavior. Thrushes might be suitable subject species to study the role of songs within the family group.

Why signal softly? The structure, function and evolutionary significance of low-amplitude signals

“…The begging calls of altricial songbirds, for example, signal information relating to offspring quality and level of need (Horn & Leonard, 2002;Soler & Aviles, 2010). The parents of some bird species produce low amplitude feeding calls that may serve to signal the arrival of food to the offspring and/or as a sign of nest relief to the other parent (Ishizuka, 2009). Female superb fairy-wrens (Malurus cyaneus) are also known to produce a vocalization during incubation, which the offspring appear to learn in the egg and produce after hatching thereby allowing the parents to distinguish their own offspring from the offspring of brood parasites (Colombelli-Négrel et al, 2012).…”

Is the Soft Song of the Brownish‐Flanked Bush Warbler an Aggressive Signal?

“…Soft songs can be used in combination with broadcast songs (Lampe & Espmark ; Dabelsteen & Pedersen ) or separately in the contexts of aggression or courtship (Dabelsteen et al. ; Morton ) or in the feeding of young (Ishizuka ).…”

“…Soft songs share some acoustic features with broadcast songs but differ in others (Anderson et al 2008;Ballentine et al 2008;Reichard et al 2011). Soft songs can be used in combination with broadcast songs (Lampe & Espmark 1987;Dabelsteen & Pedersen 1990) or separately in the contexts of aggression or courtship (Dabelsteen et al 1998;Morton 2000) or in the feeding of young (Ishizuka 2009).…”