We were working in the Peel Inlet on Sunday October 16 when we came across a deceased dolphin.
The female dolphin, identified as Hakuna, was floating at the surface belly up, and she was not alone.
A male dolphin very well known to us, Squeaky, was by her side, carrying her body by swimming under her and grabbing her by locking their pectoral fins together.
Sometimes Squeaky would also swim directly behind Hakuna’s body and push her forward from her tail or swim to the side and rest his rostrum on her underside.
We followed the pair for five hours and during this time Squeaky did not rest, nor did he eat.
He was also very protective of Hakuna’s body, placing himself between her and our boat.
It is not unusual to see mothers carry their deceased newborn calves for a period of time after the calf’s death.
An adult dolphin carrying another is, however, a very rare occasion to witness with only a couple of such events reported in the world.
After a couple of hours of following Squeaky, we were surprised by an even more rarely observed behaviour: Squeaky proceeded to copulate with deceased Hakuna.
There is nothing unusual about dolphins engaging in nonreproductive sexual behaviour but engaging in necrophilia is something that has not been reported or observed many times before.
Mandurah dolphins keep surprising me with their complex and varied behaviour.
This time I cannot help but wonder whether dolphins have the capacity to perceive death and whether they engage in some form of mortuary practices.
Unfortunately Hakuna leaves behind a calf Matata, the second orphaned dolphin that we know of in the Mandurah waterways.
Matata should be old enough to survive on her own and we have already seen her once spending time with other mums and calves in the Mandurah Channel.
The Mandurah Dolphin Research Project is a partnership between Murdoch University, City of Mandurah and Mandurah Cruises that commenced in January 2016.
They are measuring how many dolphins use the Peel-Harvey waterways and how they are connected to dolphins in nearby coastal waters.
You can follow the project on Facebook or through this fortnightly column.
