What are Pilot Whales ?
Pilot whales are cetaceans that belong to the genus Globicephala. Well now you must be wondering what cetaceans are right ? Cetaceans are aquatic mammals constituting the infraorder Cetacea. There are around 89 living species. The smallest cetacean is the vaquita, at 1.5 m (4 ft 11 in) and 43 kg (95 lb); the largest is the blue whale, at 29.9 m (98 ft) and 173 t (381,000 lb)
Getting back to the main subject “Pilot whales”, there are two main species of pilot whales. They are;
- Long-finned pilot whale (G. melas)
- Short-finned pilot whale (G. macrorhynchus)
These two species of pilot whales aren’t that distinguishable at first sight. The best way to distinguish these two species from each other is by conducting an analysis of their skulls.
Pilot whales can be found throughout the world. Long finned pilot whales are most likely to be found living in cold waters whereas short finned pilot whales are found in more warm tropical and sub-tropical waters.
Pilot whales aren’t actually whales
Pilot whales, even though they possess the name whales aren’t actually whales. According to Dr.Emma Betty, of the Cetacean Ecology Research Group at Massey University in New Zealand, pilot whales are actually large dolphins.
“The name doesn’t fit them – they’re actually a large dolphin,” – Dr Emma Betty
According to history, evolution and research, Pilot whales are more related to bottlenose dolphins than to humpback whales.
Behaviour of Pilot whales and living in pods
- Pilot whales prefer to eat squid, but they’ll also consume fish. They are estimated to eat about 70 pounds of food daily.
- Pilot whales usually travel in matriarchal pods containing on average 7-15 individuals and can range up to hundreds when they gather in groups.
- They are highly social animals, and researchers say that both males and females remain in their mother’s pod.
- Pilot whales have one of the longest birth intervals of all cetaceans, calving once every three to five years. Once a female is no longer able to reproduce, she contributes in providing important ecological knowledge of where to find food, etc. as well as helping in the care of the group’s juveniles.
Why are pilot whales getting stranded?
Since of recent, several news have emerged of Pilot whales being found stranded on beaches. The pilot whale received its name due to the belief that the pod follows a single leader. Studies have shown that group strandings tend to be of mostly healthy pilot whales. Scientists are not certain why these mass strandings occur, especially when so many of the beached whales are healthy, but it’s believed that their strong social bonds contribute to these events. Other reasons being studied include navigational errors made when following prey or caused by irregularities in the earth’s magnetic field, or possible parasitic infections resulting in neurological disorders
One of the main issues for mass pilot whale strandings are navigational errors by the leader of the pod. As these animals use echolation for navigation, foreign geographical features affect their technique of navigation.
Studies have shown that these groups are also susceptible around beaches which gently slope across a wide area – because the whales’ sonar pulses can fail to detect the shoreline in shallow waters.
Major Pilot Whale Strandings
- In September 2020, some 470 pilot whales were stranded in Strahan, Tasmania. As of 25 September around 350 of the whales had died, while 94 had so far been rescued.
- In November 2020, 120 pilot whales were stranded in the Panadura coastline in Srilanka. Due to the efforts of country’s navy and volunteers all but 5 whales were rescued.