(Table 1) Mean statistics for acoustic parameters measured for both brown skua (Catharacta antarctica lonnbergi) sexes

• Main Authors: Janicke, Tim, Ritz, Markus S, Hahn, Steffen, Peter, Hans-Ulrich
• Format: Dataset
• Language: English
• Published: PANGAEA 2015
• Subjects: Amplitude; standard deviation; Bandwidth; Biological sample; BIOS; Duration; Frequency; Number; Percentage; Potter_Pen; Potter Peninsula; King George Island; Western Antarctica; Priority Programme 1158 Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas; Relief type; Repetition rate; Sex; Species; common name; SPP1158; Time in seconds; Antarc*; Antarctic; Antarctica; Brown Skua; Sea ice
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.848403; https://doi.org/10.1594/PANGAEA.848403

Bird vocalisations are often essential for sex recognition, especially in species that show little morphological sex dimorphism. Brown skuas (Catharacta antarctica lonnbergi), which exhibit uniform plumage across both sexes, emit three main calls: the long call, the alarm call and the contact call. We tested the potential for sex recognition in brown skua calls of 42 genetically sexed individuals by analysing 8-12 acoustic parameters in the temporal and frequency domains of each call type. For every call type, we failed to find sex differences in any of the acoustic parameters measured. Stepwise discriminant function analysis (DFA) revealed that sexes cannot be unambiguously classified, with increasing uncertainty of correct classification from contact calls to long calls to alarm calls. Consequently, acoustic signalling is probably not the key mechanism for sex recognition in brown skuas.