05/03/2026
Today the ORCA Foundation, together with the team, joined forces for a Humpback Dolphin survey in Plettenberg Bay. It was also a great opportunity to learn from Dr Alejandra Vargas, who shared her knowledge about hydrophones and helped ensure that our acoustic monitoring equipment is working at 100%.
Humpback dolphins (Sousa plumbea), also known as Indian Ocean humpback dolphins, are one of the most fascinating and vulnerable marine mammals found along the South African coastline. They are coastal specialists, meaning they live very close to shore—often within just a few hundred meters of the coastline and in waters less than 25 meters deep. This makes areas like Plettenberg Bay incredibly important habitat for them.
Humpback dolphins are typically seen in small groups moving through the bay, often travelling or feeding along the coastline. Unlike some dolphin species that form large pods, these dolphins usually travel in groups of 2–10 individuals, making each sighting a special moment for researchers and ocean lovers alike.
Humpback dolphins are currently classified as Endangered on the International Union for Conservation of Nature (IUCN) Red List, highlighting the importance of monitoring and protecting the habitats where they occur.
Because they live so close to shore, humpback dolphins face several threats, including coastal development, boat disturbance, fishing gear entanglement, and noise pollution. This is where tools like hydrophones become incredibly valuable. By listening to underwater sounds, researchers can monitor dolphin presence, behaviour, and the acoustic environment without disturbing them.
The work being done in Plettenberg Bay contributes to protecting this important population within the Mission Blue Hope Spot network, helping scientists and conservationists better understand how these dolphins use the bay and how we can safeguard their habitat for future generations.
And a big thank you to for always providing us with the use of a skipper and vessel.
