Ways of developing acoustic signals in birds

Abstract

An analysis of Russian and foreign literature data on the ways of developing acoustic signals in birds is presented. The physical analysis of acoustic signals is given for six species of birds: long-tailed skua (Stercorarius longicaudus Uicill), herring gull (Larus argentatus Pontopp.), sabine’s gull (Xema sabini sab.), curlew sandpiper (Calidris ferruginea Pantopp.), red-throated diver (Gavia stellata Pontopp.), and black-throated diver (Gavia aterica L.). Signals of embryos, baby birds, and adult birds are considered. The denervation of the syrinx in baby and adult birds was investigated to obtain a pattern of generation of acoustic signals in the absence of syrinx innervation. The temporal-frequency signal characteristics are compared to those of decapitated birds. The examples of acoustic signals of these birds confirm the significant role of the physical characteristics of morphological structures participating in the generation of acoustic signals in birds.