of Free-Swimming Female Indo-Pacific Bottlenose Dolphins (Tursiops aduncus)
Mating tactics have been studied more in male than female dolphins. In some populations of Indo-Pacific bottlenose dolphins (Tursiops aduncus), males are aggressive and females may have limited control of mates. If females exercise active mate choice, we predicted their responses to male behaviors would differ from chance expectations. Fourteen underwater video recordings were analyzed of mating-affiliated sequences off the coast of Hurghada, Egypt. The videos were transcribed in Transana and individual behaviors were tallied from an ethogram containing nineteen behaviors. A log likelihood test was used to determine if females responded differently to particular male behaviors.
Behaviors were pooled into four categories for females and six categories for males. Female behavioral responses to preceding male behaviors varied from chance expectations (G2=72.13, d.f.=1.5, and p<0.01). Furthermore, each female behavior was preceded by a different male behavior more than expected. However, female behaviors did not vary from chance following male copulation attempts. Female behaviors appear to be influenced by preceding male behaviors, suggesting females are capable of active discrimination among males. Variable female responses immediately following copulation attempts could indicate high costs associated with resistance. Recordings of mating behaviors of free- swimming dolphins can broaden our understanding of female mate choice.
Jessica Hillhouse ¹, Dara N. Orbach ¹, Angela Ziltener ² ³, Bernd Würsig ¹
¹ Department of Marine Biology, Texas A&M University at Galveston
² Dolphin Watch Alliance, Switzerland
³ Anthropological Institute and Museum, University of Zurich, CH-8057 Zurich, Switzerland
Texas A&M University at Galveston