New Publication: Postpartum signature whistle production in bottlenose dolphins

Photo Credit: Donald McMullen/Dolphin Research Center

We are very pleased to announce the publication of our recent study on postpartum signature whistle production in bottlenose dolphins, published in the journal Marine Mammal Science.

Authors; Stephanie L. King, Emily Guarino, Katy Donegan, Jane Hecksher and Kelly Jaakkola.

Summary: Individual vocal signatures play an important role in facilitating maternal care in many animals. In those species where neonates are precocial immediately following parturition, the need for individual recognition between mother and offspring is paramount. In bottlenose dolphins such acoustic recognition signals, termed signature whistles, have been shown to be pivotal in mother-offspring recognition. Here we explored how female bottlenose dolphins used their signature whistle in the weeks leading up to and following the birth of their calves. We show that females significantly increased signature whistle production immediately after the birth of their female calves (LMER, P < 0.0001). Average signature whistle rate increased from 0.14 whistles/min to 0.78 whistles/min, representing a > five-fold increase in postpartum signature whistle production, with rates remaining high for four weeks after birth. Our findings complement those of Fripp and Tyack (2008), and offer further support to the imprinting hypothesis, where calves imprint on their mothers’ signature whistles immediately after parturition. The increase in maternal signature whistle use facilitates the calf’s recognition of its mother’s call before mother-calf separations occur. These results highlight the importance of postpartum signature whistle use in aiding mother-calf recognition in bottlenose dolphins and provide insight into one of the underlying mechanisms that aids mother-offspring recognition in species with precocial young.

You can access the paper here: http://onlinelibrary.wiley.com/doi/10.1111/mms.12317/full