Pilot Whale

There are two species of Pilot whales in Western Australian waters, the Long Finned pilot whale, found mainly in the southern part of the state in cool temperate waters and the Short Finned Pilot whale, which primarily habituates tropical waters. Both species are very similar and extremely hard to differentiate. The main difference being that the Long Finned pilot whale has longer pectoral fins. These whales are different to Humpbacks and Southern Right whales in that they are toothed whales, they do not have baleen plates and because of this, their diet is vastly different. They eat larger oceanic fish like tuna & salmon. Pilot whales are deep divers and their main diet consists of squid for which they dive deep to hunt. Other whales that are toothed whales include Killer whales, False Killer whales and Sperm whales.

Pilot whales are also much smaller than a Humpback or Southern Right, with the male on average, being up to 7.5 metres in length and females around 5.5 metres in length. Pilot whales have a very distinct body shape. Their skin is jet black and their dorsal fins are large, curved and very wide. Their most distinctive feature is their big round head. Their pectoral fins are reasonably long, swept back and curve to a very fine point at the tip. Unlike baleen whales like Humpbacks and Southern Rights that are primarily lone animals, pilot whales are highly sociable animals and live in relatively large family groups of up to 50 animals with some groups exceeding a thousand animals. One of the reasons for this is that these animals primarily live offshore in deep water and living in a group provides better protection from predators.

Because both species of pilot whales inhabit deep, offshore waters it is very rare to see them close to shore. However, pilot whales are notorious for stranding on shallow beaches and this is when they are mainly sighted. It is unknown why they strand, but many factors may combine to make them do so. These factors include sick or injured animals in the group, bad weather conditions and even gently sloped sandy beaches is thought to confuse their navigation system, causing the animals to become disoriented, making navigational judgement errors and beaching themselves. When these whales strand they cause major problems for rescuers.

Because the bond with the animals in the group is so strong they all stay together. If one animal is sick and strands itself in shallow water, even if the other animals in the group are healthy, they will stay with it and then eventually they too become stuck in the shallows. Once a big group is stranded they succumb to sunburn and dehydration due to being out of the water and the problem compounds itself. If the group has young calves, they cannot feed from their mothers and eventually, they too, become sick and die.

There have been many mass strandings of pilot whales along the Western Australian coast. The Department of Environment & Conservation (DEC), has constant training programs and emergency contingency plans in place to react to these events. With the help of concerned members of the public, DEC has been extremely successful in rescuing and returning this species of whale to the wild. Although not in Australian waters, unfortunately, both species of pilot whale are still hunted in some places around the world.