30.03.2019 – Cosmopolitan

Our Stenella set out onto a placid ocean to meet a group of calm, logging Short-finned pilot whales (Globicephala macrorhynchus) that didn’t seemed disturbed by our presence in the very least. Before long, we continued to a group of Bottlenose dolphins (Tursiops truncatus) that were travelling not too far from the pilot whales.

Bottlenose dolphins are extremely widely distributed with the genus containing three species that are segregated in their distribution; the Common or Atlantic Bottlenose dolphin (the species we regularly encounter), the Indo-Pacific Bottlenose dolphin (Tursiops aduncus) and the Burrunan dolphin (Tursiops australis). The genus is also particularly notorious for its curiosity and is often seen socializing with other cetacean species. Such associations are generally harmonious, particularly those with Short-finned pilot whales or with False orcas (Pseudorca crassidens). However, Bottlenose dolphins can also be real bullies, with smaller delphinids like the Short-beaked common dolphins (Delphinus delphis) or the Atlantic spotted dolphins (Stenella frontalis) often actively avoiding them. We even once caught them annoying a young Sperm whale (Physeter macrocephalus) calf in the midst of a socializing situation amongst these large giants of the oceans. So they aren’t just curious, they’re also quite gutsy.

Their interactions with pilot whales are the ones we observe most frequently but their broad distribution and opportunistic nature also means that the species come into contact with all sorts of marine organisms. Research is still being done on the motives of these interspecial interactions but many scientists agree on one thing; they are usually instigated by this highly cosmopolitan cetacean.

By Paula Thake

Sightings of the day

Stenella

15:00 Bottlenose dolphins, Short-finned pilot whales