Learn all about the unmistakable pilot whale, from their diet and size to life in the pod and why, sadly, they’re prone to beaching

By Whale and Dolphin Conservation (WDC)

Published: Monday, 17 July 2023 at 12:00 am


What do pilot whales look like?

Pilot whales are long, robust whales and have a thick-set, curved (sometimes hooked) and very prominent dorsal fin. The head is bulbous with no beak.  Male pilot whales are larger than females, and they have a more bulbous forehead and chunkier dorsal fin.

Adult pilot whales are black or dark grey and have a lighter grey saddle patch on the back behind the dorsal fin and an anchor-shaped patch on the underside. Pilot whale babies are paler coloured.

Where do pilot whales live?

Pilot whales live throughout the cold and temperate waters of the southern hemisphere and in the North Atlantic Ocean; they have a wide distribution around the globe.

How many species of pilot whale are there?

Long-finned pilot whales are one of two species of pilot whale, the other being short-finned pilot whales – both named for the ‘relative’ length of their pectoral fins. Their distributions do overlap in some parts of the world and it’s very difficult to distinguish between the two.

They differ only slightly in physical size, features, colouration and pattern. Other close relatives of the pilot whale are the melon-headed whale, the pygmy killer whale, the false killer whale and Risso’s dolphin.

Why are they called pilot whales?

The ‘pilot’ part of their name comes from an old theory that each pod is piloted by a single leader, but this is not actually the case (although the name has stuck).

How big are pilot whales?

Male pilot whales are up to 6.7m long, while females are slightly shorter at 5.7m. Calfs are approximately 1.8m long. Males are heavier than females – weighing around 2,300kg compared to the the female’s 1,300kg

How many teeth do pilot whales have?

As with other squid consumers, an evolutionary reduction of teeth means that long-finned pilot whales have notably fewer teeth than most other delphinids with between 9 and 12 teeth in each row. It’s almost impossible to distinguish the species at sea as there are only subtle differences between the two species of pilot whale. The long-finned pilot whale has a narrower skull, slightly longer flippers and more teeth – a short-finned pilot whale has between 7 and 9 teeth in each row.

Do they form pods?

Yes, they live together in multi-generational, tight-knit, stable pods. There are usually more females than males as their pods are built on units of mothers and their offspring.

Older females, or those who are not giving birth themselves, help mothers in the pod care for their babies. Pilot whales are strongly bonded to each other and do everything together – resting, hunting, socialising, playing and travelling as a unified pod.

The most important thing in their lives is each other and they are incredibly loyal. There can be anything from 10 to 20 all the way up to 100 pilot whales living together in a pod. Huge multi-pod get-togethers of hundreds or even a thousand pilot whales give ample opportunity for males to mix and breed with females from other families.

How long will the calf stay with their mother?

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Pilot whale with her calf © Getty Images

Baby pilots grow up within the safety of the pod they are born into and remain within the same pod for life. Calves can be nursed for around 3 years, one of the longest in all mammal species.

What do pilot whales eat?

Mainly squid and octopus – these cephalopods are definitely their favoured food. They do sometimes eat fish such as mackerel, hake, herring and cod. Pilot whales ‘ram and suck’ squid into their mouths, which are adapted for sucking rather than grasping prey.

How do they track their prey?

Pilot whales can dive to depths of over 600m for 10-16 minutes at a time to hunt. They mostly feed at night in deep water using echolocation to find prey.

Do they use teamwork when feeding?

Possibly. They use echolocation to forage but studies show that they are more vocal when socialising than any other time.

Do they come to the surface for long?

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Short-Finned Pilot Whale Breaching © Getty Images

Pilot whales are often active at the surface; they may spyhop (poke their heads out of the water), or lobtail (lift their flukes out of the water and splash them down). They are also regularly seen resting (logging) in unison, close to each other at the surface.

 

How long do pilot whales live for?

Females generally live longer than males. Their lifespan is 60 years, compared to a male’s 45 years.

 

How fast can pilot whales swim?

Fast! They’ve been known to engage in chases with orca and Risso’s dolphins, both of which aren’t slow!

How intelligent are pilot whales?

The current best predictor of quantifying ‘intelligence’ of a species is the number of neurons in the forebrain. The long-finned pilot whale has almost twice as many as humans and more than any mammal studied to date, with the exception of the orca.

Do they interact with other species of whale or dolphin?

The sociable nature of pilot whales means they are often seen swimming with dolphins in mixed-species pods including common dolphins and bottlenose dolphins, but also other species such as Atlantic white-sided dolphins and minke whales.

What sounds do pilot whales make?

As with other species of cetacean they make a variety of different sounds including squeaks, whistles, buzzes and echolocation clicks. Long-finned pilot whales also appear to use ‘repeated sequence’ calls primarily when socialising.

Are they aggressive?

Long-finned pilot whales have strong social bonds and have been observed harassing, mobbing and chasing other species including Risso’s dolphins and orca.

Do pilot whales have natural predators?

An adult will have no natural predators. However, a calf may be appealing to orcas, which explains why sightings of ‘aggression’ between the species has been documented.

What are the main threats to pilot whales?

Hunting – the social nature of pilot whales means that unfortunately it is easy for humans to herd them together and push them in a certain direction. Around 850 long-finned pilot whales are still hunted every year in the Faroe Islands.  The hunts are controversial as killing methods are considered inhumane and whale meat is no longer needed for human survival. Hunters use small boats to frighten the whales and herd them into shallow bays in the Faroes. They then slaughter the whole pod in shallow water using large knives. Pilot whales are also hunted elsewhere, such as in Greenland and Saint Vincent and the Grenadines.

Pollution – toxic chemicals from plastics, litter and oil spills build up in pilot whales, seriously harming their health and their ability to have young. The toxic nature of their meat also means they pose a risk to human health if eaten.

Fishing gear – pilot whales get accidentally caught in fishing nets and lines, injuring or even killing them.

Noise pollution – pilot whales live in a world of sound, and increased noise in the oceans from human activities has an impact on their lives.

What causes pilot whales to strand on beaches?

Sadly, perhaps the thing that pilot whales are most famous for is their tendency to mass strand on beaches. We simply do not know why large numbers of healthy whales strand together like this. In many cases the cause simply cannot be determined.

We are sure that the strong bonds between them and their propensity to stick together and follow one another plays a big role in these stranding events, whatever the underlying reasons might be. Possible causes are navigation mistakes when following prey or travelling (perhaps due to irregularities in the magnetic field), or possible parasitic infections resulting in neurological disorders, or perhaps the whole pod simply sticks together to support an ill whale.