PHNOM PENH, May 31, 2024 – Researchers conducting dolphin surveys in Prek Tnaot, Kampot, have made a fascinating discovery—a newborn Irrawaddy dolphin calf accompanied by a group of Indopacific humpback dolphins. This unusual sighting raises intriguing questions about interspecies interactions.

Typically, these two dolphin species share overlapping territories and are observed together while foraging, but seldom do they interact closely. However, during this latest sighting, the calf, which exhibits all the defining characteristics of an Irrawaddy dolphin, was seen under the care of an adult Irrawaddy, assumed to be its mother. While hybridization between these species has occurred on rare occasions, researchers believe this is unlikely to be the case here.

Experts are exploring two possible explanations for this phenomenon:

Alloparenting, where an adult provides care for a non-biological offspring, sometimes even across species lines. Such behavior has been previously documented among these dolphins, though it remains a rarity.

Instances of aggression or sexual aggression, as observed in past interactions where male Indo-Pacific dolphins have been known to attempt separating mothers from their calves.

The research team continues to monitor the group closely, with repeated sightings of the calf suggesting that it has been accepted and is receiving care from the presumed mother. Identification efforts through photo recognition have been successful, though determining the sex of the dolphins relies on observing their social interactions.

As observations continue, further details about these unique interspecies dynamics will be forthcoming.