Identification Guide

Most cetaceans spend only limited time at the surface and even then they are only partly visible above the waterline or are travelling in a fast blur of froth. So, identifying the different whales and dolphins can be frustrating if you don't know what to look for. To help you cope with these limitations, the following guidelines - together with the characteristics described in whale descriptions - will help you distinguish between the different species of cetaceans found in these waters.

Group of dolphins porpoising

Dolphin surfacing to breath

Dolphins are especially easy to recognise when they show (off) their typical behaviour: porpoising
The way they surface to breath (see figure on the right) also sets them apart from larger fish, like sharks, which have their tail fins vertically above the water.

Risso's dolphin Pilot whale

Though risso's dolphins are much smaller than pilot whales, both lack the dolphin type beak and tend to log at the surface. You shouldn't see a blow or a "flukes up" with these two.
The most striking differences between these two cetaceans are:

Scars: Risso's dolphins (especially older males) tend to be covered in scars, whereas pilot whales are darker and have no scars at all.

Visible contours of body: The pilot whale is more rectangular and squad. Risso's dolphins are more curved, yet more "barrel-shaped" then other dolphins. The pilot whale's dorsal fin is typically pointing aft.
Behaviour: Risso's dolphins are much more agile and playful, and - although both are very inquisitive - pilot whales are much less boisterous.

Diving Fin whale

Diving Sperm whale

Finally, size matters and an animal larger than ten metres indicates either a sperm whale or a fin whale. The most striking differences between these two cetaceans are :

Blow: A blow that is projected forward-left indicates a sperm whale. A vertical (narrow) blow indicates a fin whale.
Flukes: If the animal dives "flukes up" then again it is a sperm whale. Have a look at some animated photos of this behaviour.
Visible contours of body: Fin whales display a curved section of their body above the surface, contrary to sperm whales, which resemble floating objects like containers or timber.
Number of blowholes: The Mysticeti (fin whales) have two blowholes or nostrils, whereas the Odontoceti (sperm whales, dolphins, pilot whales etc.) have just one.