Why do Whales Beach Themselves?

Reasons Why a Whale Becomes Stranded on Land

Sep 18, 2009 Roberta Goli

Beached whales often die despite the best efforts of those trying save them. Often the damage is already done as a result of being out of the water.

Whales become beached or stranded for a number of reasons. Beaching or stranding is when a whale becomes stuck on a beach or sand bar and is unable to move. Often the help of humans is futile because the mammal has already suffered severe damage due to being out of the water for a length of time.

Why Whales Beach Themselves

It is common knowledge that from time to time whales beach themselves. It is not common knowledge as to why they do this; however, there are several likely causes. These are:

Due to illness or injury
Interference with the whale's navigation system, causing confusion – military SONAR use in area
Confusion caused by unusual coastline formations - it is thought that echolocation may not be able to detect slight slopes in seabed and coastline
Whales become stranded during low tide
Group beaching is believed to be as a result of a "follow the leader" type of scenario where the leader unfortunately is confused, or when pod members respond to a distress call from a stranded whale
Lack of food causes weakness and dehydration
Hunting too close to shore
Natural reasons such as rough weather
Old age
Difficulty giving birth
Due to attacks from predators (i.e., killer whales)

Why Beached Whales Often Die

Despite people’s best efforts to save beached whales, many die anyway as a result of being out of the water. Due to their large size and body weight, without the supporting water, whales can suffer from kidney failure and their weight causes damage to muscles causing the release of the protein myoglobin.

Myoglobin transports oxygen throughout the whale’s body, but when a whale is out of the water, the extra myoglobin that is released is toxic to the kidneys. The whale’s respiratory muscles also suffer due to its weight and fail to function properly. Damage can also occur to areas of the body that are in contact with the ground. There is also risk of drowning if high tide arrives and the water covers the whale's blowhole.

Euthanasia is often a kinder alternative to returning beached whales to the sea, because often the damage is already done and returning the animal can cause more suffering. Beached whales will often die of complications that they endured from being out of the water and many continue to re-beach themselves.

Resource and further reading:

For more information visit the New Scientist story Killing Beached Whales is Kinder, experts say.

You may also like to read Echolocation in Whales and Dolphins and Humpback Whale Facts.