Individual variation in pup vocalizations and absenceudof behavioral signs of maternal vocal recognitionudin Weddell seals (Leptonychotes weddellii)

摘要

Individually stereotyped vocalizations often play an important role in relocationudof offspring in gregarious breeders. In phocids, mothers often alternate between foraging at sea and attending their pup. Pup calls are individually distinctive in variousudphocid species. However, experimental evidence for maternal recognition is rare.udIn this study, we recorded Weddell seal (Leptonychotes weddellii) pup vocalizationsudat two whelping patches in Atka Bay, Antarctica, and explored individual vocaludvariation based on eight vocal parameters. Overall, 58% of calls were correctly classified according to individual. For males (n = 12) and females (n = 9), respectively,udnine and seven individuals were correctly identified based on vocal parameters. Toudinvestigate whether mothers respond differently to calls of familiar vs. unfamiliarudpups, we conducted playback experiments with 21 mothers. Maternal responsesuddid not differ between playbacks of own, familiar, and unfamiliar pup calls. Weudsuggest that Weddell seal pup calls may need to contain only a critical amountudof individually distinct information because mothers and pups use a combinationudof sensory modalities for identification. However, it cannot be excluded that pupuddevelopmental factors and differing environmental factors between colonies affectudpup acoustic behavior and the role of acoustic cues in the relocation process.