A recent seminar organised by HuDoNet (Indian Ocean Humpback Dolphin Conservation Network) brought together six researchers to share their research on Indian Ocean humpback dolphins and other coastal cetaceans. Originally presented at the Society for Marine Mammalogy’s Biennial Conference (SMM24), the talks highlighted challenges facing these endangered animals, as well as the cutting-edge methods scientists are using to protect them. The quality of all six presentations was exceptional!
Imran Samad set the tone for excellence, sharing how he combined particle tracking and stranding data to infer humpback dolphin mortality in Goa, India. By modelling the effects of ocean currents on carcass stranding probability, he demonstrated that the number of dolphins washing ashore represented only 70-80% of the total mortality, and emphasised the need for seasonal population surveys to accurately assess the impact of mortality. He considered how to improve our understanding of the causes of mortality and ways to refine the model.
From bustling Mumbai, Shaunak Modi set the scene of prolific coastal development, unchecked sewage pollution, and intense fishing, all within the spaces humpback dolphins use. He conducted a risk assessment using boat-based observations and interviews with fishers. He found local fishers had surprisingly positive attitudes towards dolphins despite net depredation and that large scale commercial fisheries, coastal development and climate change are larger, more immediate threats to dolphins and the fishers. Note that Shaunak won the Leatherwood Award for his presentation!
Further south in Sindhudurg, Ketki Jog used a mix of ecological and social surveys to investigate fishery interactions with dolphins. She found much overlap between dolphins and fishers, identifying eight high-risk areas. And while dolphins damage fishing gear and reduce catches, small-scale fishers ranked other challenges—such as resource depletion from industrialised fishing, extreme weather, and inflation—as more pressing concerns and called for stricter fisheries regulations to curb illegal practices. Ketki’s research highlights the need for a livelihoods-based approach to managing human-wildlife interactions, ensuring that conservation efforts address both ecological and socio-economic concerns.
Switching species but still in Sindhudurg, Isha Bopardikar demonstrated how acoustic monitoring can help track Indo-Pacific finless porpoises, which are notoriously difficult to study visually. By deploying a hydrophone array that detects the porpoises’ high-frequency clicks, Isha was able to produce the first reliable density estimates in her study area. Her findings point to worrying declines, likely driven by overlapping pressures from fishing, especially trawlers. It will be interesting to see how this compares when Isha analyses the Sousa data.
Presenting from Dubai, Bryana Cope shared a cautionary tale of dolphins on another highly urbanised coastline. Boat-based surveys, citizen science reports, and passive acoustic monitoring all revealed the year-round presence of bottlenose dolphins and finless porpoises, yet a dramatic drop in humpback dolphin sightings compared to a decade ago. Rapid development is likely a major factor in this alarming decline, underscoring the urgent need for stricter conservation measures.
Finally, nearly-Dr. Sasha Dines showcased her SWORD framework (Signature Whistles for Occurrence, Recapture, and Density), developed to monitor humpback dolphins off South Africa. By identifying individual dolphins via their unique “signature whistles,” she mapped their movements and estimated population sizes across their south coast range. This acoustic approach could transform how scientists monitor elusive coastal species, providing a reliable and cost-effective alternative to traditional mark–recapture studies.
Overall, these six presentations underscored both the severity of threats facing coastal cetaceans and the ingenuity of researchers determined to protect them. Whether through community-focused initiatives, sophisticated acoustic tools, or multi-method monitoring, these studies take us closer to evidence-based strategies to conserve humpback dolphins.
Watch this space. Future seminars are already being planned…
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