Why do whales strand themselves?

As nearly 400 pilot whales died in Australia’s largest mass stranding on record, scientists point to a number of potential reasons which could explain the phenomenon, including navigational errors


Long-finned pilot whale: 
Species of oceanic dolphin 
Max. length: 7 metres
Max. weight: 3 tonnes

Travel in large, close-knit communities which rely on constant communication

ECHOLOCATION: Toothed whales – including dolphins – use type of bio sonar to navigate and find prey

Blowhole
Phonic lips
Melon
Jaw
Nasal passages
Inner ear
Brain

1 2. 3 

1 Sound waves generated by vibration of phonic lips – vocal cord- like membranes – pass through melon – fatty cavity used like sound box

2 Echoes bounce off obstacles and return to animal
 
3 Hollow, fat-filled lower jaw receives sounds, which then travel to inner ear to be interpreted by brain


Some theories link strandings to failure of whales’ sonar pulses to detect shoreline in shallow waters

One leading individual – maybe in poor health – could mistakenly lead whole group to shore

Disruptions of Earth’s electromagnetic field, caused by solar storms or earthquakes, may disturb navigation

There is also strong connection between active sonar – such as naval sonar – and strandings


Sources: Society for Marine Mammalogy, Project Jonah
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