Adopted or kidnapped?
Something very interesting is happening with a local pod of bottlenose dolphins. The pod has either adopted or kidnapped a calf of an entirely different species, the common dolphin.
Bottlenose dolphins are a familiar site around the Hibiscus Coast because they frequently come close to shore, especially around this time of year. They are big dolphins, sometimes mistaken for orcas, and they often delight nature watchers by doing spectacular leaps and jumps.
In late July, there was a sighting of a pod of ‘bottles' at Little Manly Beach that was reported on the whale and dolphin watch Whangaparāoa Facebook page, and so I went around to have a look. There was about a dozen of them, including little ones, and they hung about for a quite a while– it was wonderful to see.
Later, I posted some video footage I had shot of the dolphins on social media, and Blair Outhwaite and Catherine Lea, local marine mammal experts, immediately picked up on something very unusual. One of the calves was not a bottlenose, but a common dolphin.
Commons are a much smaller species, and not often seen so close to shore. There are decent numbers of common dolphins in the Hauraki Gulf, but you typically see them from a boat because they have a much more pelagic (open sea) lifestyle.
I asked Massey University Associate Professor Karen Stockin, a leading dolphin biologist, what this common dolphin calf could be doing with the bottlenose dolphins. One possibility is that a mother bottlenose may have lost her own calf and kidnapped the calf of a common dolphin. Dr Stockin suggested, however, there was a higher likelihood that the pod of bottlenoses had adopted a deserted or orphaned calf. She remarked that the calf looked to be struggling somewhat, appearing weak – with the bottlenose dolphins initially needing to support the calf up at the surface. The size of the common dolphin indicates it may be partially weaned, so we can't be sure if the calf has nursed from a bottlenose or not. However, given the calf's condition, the prospects of the common dolphin surviving seemed low.