24.08.2024 – Friend or Foe ?

An interesting sighting. On both our morning and afternoon tours (09:30 and 17:00), we saw short-finned pilot whales (Globicephela macrorhynchus), and on both tours, we noticed the family group was joined by an interesting stranger—one singular bottlenose dolphin (Tursiops truncatus). It is not uncommon to see Bottlenoses associating with other species. Over the last months, I’ve seen bottlenose following, swimming with or just being suspiciously close to Common (Delphinus delphis), Spotted (Stenella frontalis), and Rough Toothed (Steno bredanesis) dolphins. But what’s at the root of these interactions? They’ve not only been observed in bottlenoses, but both common and spotted dolphins have been recorded playing, hunting, and even babysitting each other’s calves. It seems, in a similar vein, bottlenose likes to interact with larger members of the dolphin family, especially pilot whales, as weve seen. These interactions are mainly peaceful and could occur because both animals are reacting to similar chemical cues when hunting for fish or squid. 

However, Bottlenose have a huge brain-to-body ratio (second amongst the mammals only to humans (Homo sapiens). As with humans, “intelligence” comes not only with good but also sometimes a propensity for violence. Bottlenose are known for cruel intraspecific behaviour, which is part of the reason why, to myself and other guides, they often have a bad distrustful reputation. So while I will spare you the sometimes brutal details, it should be known that when these interactions occur (especially with smaller dolphins), they are not always peaceful. Ultimately, unlike the beautiful coastal waters of Madeira Island, things aren’t always clear when it comes to arguably one of the most intelligent creatures.

By Peter Worth

Sightings of the Day

Ribeira Brava

09:30 Pilot Whales, Bottlenose Dolphin

13:30 Bottlenose Dolphin

Stenella

09:30 Pilot Whales, Bottlenose Dolphin, Sperm Whale

14:00 Bottlenose Dolphin

17:00 Pilot Whales, Loggerhead