Female dolphins identify males by their calls and keep a record of their past behavior, choosing to avoid the most aggressive males during mating season.
These displays may be to impress females or engage in affiliative behaviors such as touching or petting.
According to , males work together to gain access to females, aggressively driving them into mating events that could last from hours to weeks.
“They restrict the female’s movements. They want to keep her in the areas they prefer, because that way they are close to other males who can help them defend her from rivals”, explained the study’s lead author, Stephanie King.
Females observed these behaviors over time and avoided the most aggressive males.
The investigation involved a population of bottlenose dolphins (Tursiops truncated) from the Indo-Pacific of Shark Bay, Western Australia, which has been studied in depth for more than 40 years. The characteristic whistle of each male, individual behavior and the moment when adult females were ready to mate were analyzed.
Research has shown that males relied on these whistles to recognize each other and manage their relationships.
In a new one, published this Monday in PNAS, scientists collected 34 whistles characteristic of male dolphins and reproduced them underwater to 17 female dolphinsusing drones to observe their reactions.
Reproductively available females showed avoidance responses stronger to the whistles of male dolphins with higher rates of coercion.
According to the researcher, from the female’s perspective it is as if they were saying “I pay attention to the males who are more likely to chase me, and if I don’t want to be chased, I will show an avoidance response”.
“On the other hand, the females unavailablethose that were older, or with offspring and less susceptible to being targeted, did not demonstrate the same response level“, concluded King.
