Australian humpback dolphins are dark gray, with slightly fewer vertebrae than their white-and-pink neighbors, the Chinese humpback dolphins.
Given this discovery, "IUCN Red List designations for the four species will need to be assessed or revised, and the national status listings of many countries (e.g., Australia, China, South Africa) will also need to be reexamined," the scientists write in Marine Mammal Science. It's likely there are only a few thousand Australian humpback dolphins, all told, although this rough population estimate is based on sightings of the rare cetaceans.
Humpback dolphins face three major threats: commercial fishing, impacts with watercraft and "development in their coastal habitats," says Wildlife Conservation Society biologist Howard Rosenbaum, who worked with Jefferson to name the new species. "Efforts to protect humpback dolphins and other coastal dolphins, and their most important habitats, are essential for the survival of these species."