06.04.2025 – Smells and bells

The English poet, Lord Byron, famously referred to my home country, Malta, as the island of “smells and bells” due to the abundant churches scattered across our villages and the, well, smelly harbours laden with fish caught in the surrounding Mediterranean. I couldn’t help but think of that quote as we searched the ocean for dolphins with a lovely little group of guests today. The animals that made me think of it were our loyal helpers that are nearly always associated with cetacean sightings, the Cory’s shearwaters (Calonectris borealis).

Unlike humans, who rely on vision, or dolphins, who rely on sound, to map their surroundings – the Cory’s use their sense of smell to guide them across the, to us seemingly featureless, oceans. Like the rest of their tuberose cousins, Cory’s follow the distinct smell of a specific chemical, known as Dimethyl sulphide or DMS, to track down their food. DMS is released by plankton and doesn’t easily dissolve in water, lingering in the air and allowing these clever seabirds to navigate to plumes. It’s sort of an olfactory dinner bell – thus my association to Byron’s quote.

This association with feeding areas makes tubenoses reliable markers for cetacean activity and helped our spotter locate a pod of Bottlenose dolphins (Tursiops truncatus) foraging amongst the Sargassum mats and a big pod of Atlantic spotted dolphins (Stenella frontalis) farther offshore….and all this despite the sandy mist engulfing the island. And all thanks to those smells and our smart shearwaters!

By Paula Thake

Sightings of the day

Stenella

09:30 Atlantic spotted dolphins, Bottlenose dolphins