05.08.2025 – Gold nuggets

The ocean surrounding our island are teeming with life during the summer months. Stronger stratification of the water column decreases access to nutrients for deep sea animals, like squid, forcing them to migrate to shallower depths. This attracts a number of predators, including several toothed whales that enjoy gorging on these cephalopods. These include several dolphin species including the incredible Rough-toothed dolphins (Steno bredanensis) as well as the Atlantic spotted dolphins (Stenella frontalis).

But mid- and late summer are especially exciting because of the many beaked whales that visit Madeira. Unlike other toothed whales, beaked whales do not have rows of teeth in their lower jaw but rather pairs of teeth, with numbers varying according to species. They are suction feeders that spend most of their time in the deep, so its not wonder they go for the soft-bodied, nutritious deep-sea squid.

Despite their increased presence in the summer months, seeing a beaked whale is like discovering a gold nugget in Madeira, quite literally! The bodies of both species we saw today, the Blainville’s beaked whales (Mesoplodon densirostris) as well as the Cuvier’s beaked whales (Ziphius cavirostris) have a golden brown colour which comes from the presence of diatoms, an abundant phytoplankton at the surface. It’s this golden colour that usually gives them away,

By Paula Thake

Sightings of the day

Ribeira Brava

09:00 Atlantic spotted dolphins, Blainville’s beaked whales

13:00 Blainville’s beaked whales, Rough-toothed dolphins

16:30 Blainville’s beaked whales, Rough-toothed dolphins

Stenella

09:30 Atlantic spotted dolphins, Blainville’s beaked whales, Cuvier’s beaked whales

13:30 Blainville’s beaked whales, Rough-toothed dolphins

16:30 Blainville’s beaked whales, Rough-toothed dolphins