title: Maternal signature whistle use aids mother-calf reunions in a bottlenose dolphin, Tursiops truncatus.
abstract: Individual vocal signatures play an important role in parent-offspring recognition in many animals. One species that uses signature calls to accurately facilitate individual recognition is the bottlenose dolphin. Female dolphins and their calves will use their highly individualised signature whistles to identify and maintain contact with one another. Previous studies have shown high signature whistle rates of both mothers and calves during forced separations. In more natural settings, it appears that the calf vocalises more frequently to initiate reunions with its mother. However, little is known about the mechanisms a female dolphin may employ when there is strong motivation for her to reunite with her calf. In this study, we conducted a series of experimental trials in which we asked a female dolphin to retrieve either her wandering calf or a series of inanimate objects (control). Our results show that she used her vocal signature to actively recruit her calf, and produced no such signal when asked to retrieve the objects. This is the first study to clearly manipulate a dolphin's motivation to retrieve her calf with experimental controls. The results highlight that signature whistles are not only used in broadcasting individual identity, but that maternal signature whistle use is important in facilitating mother-calf reunions.
authors.affiliation: Dolphin Research Center, 58901 Overseas Highway, Grassy Key, FL 33050, USA; Centre for Evolutionary Biology, School of Animal Biology (M092), University of Western Australia, Crawley 6009, Australia. Electronic address: stephanie.king@uwa.edu.au.
authors.forename: Stephanie L
authors.initials: SL
authors.lastname: King
authors.affiliation: Dolphin Research Center, 58901 Overseas Highway, Grassy Key, FL 33050, USA.
authors.forename: Emily
authors.initials: E
authors.lastname: Guarino
authors.affiliation: Dolphin Research Center, 58901 Overseas Highway, Grassy Key, FL 33050, USA.
authors.forename: Loriel
authors.initials: L
authors.lastname: Keaton
authors.affiliation: Dolphin Research Center, 58901 Overseas Highway, Grassy Key, FL 33050, USA.
authors.forename: Linda
authors.initials: L
authors.lastname: Erb
authors.affiliation: Dolphin Research Center, 58901 Overseas Highway, Grassy Key, FL 33050, USA. Electronic address: kelly@dolphins.org.
authors.forename: Kelly
authors.initials: K
authors.lastname: Jaakkola
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D000819:Animal Communication; D000818:Animals; D050681:Bottle-Nosed Dolphin / Q000502:physiology* / Q000523:psychology; D005260:Female; D009034:Mother-Child Relations / Q000523:psychology; D009035:Mothers / Q000523:psychology; D013018:Sound Spectrography; D014828:Vocalization, Animal / Q000502:physiology
keywords: Bottlenose dolphin; Maternal care; Mother-calf reunions; Signature whistles; Vocal learning