Whale strandings - what causes them?

Keskiviikko 22.2.2023 klo 16:00 - Mikko Nikinmaa

The stranding of whales almost invariably result in the death of the animals before they can be returned to water. This is because when whales start to dry, their temperature increases since the surrounding water is not there to cool the body. The body temperature increases until it is lethal. To limit the temperature rise, stranded whales are flushed with water. During the recent past whale strandings have become more and more common. They are one of the symptoms of disturbances in oceanic environments, and may have various reasons. Regardless of the ultimate reason, it is possible that the whales make a decision to commit suicide because of the environmental stress. This can happen, as whales have very complex brains, and appear capable of conscious choices, as, e.g., commit suicide.

However, many of the strandings take place to injured whales. One of the biggest causes of whale injuries is a collision with ship. Because of the injury, the whale may not be able to swim properly and is washed ashore. Also, whales use sea currents to help them in swimming. As a result of climate change, the direction and strength of the currents may have changed so that when the whale thinks that it is swimming normally using the help of the current, it ends up stranded. By far the most important disturbance to whales is noise pollution. This is because long-distance acoustic communication is a major feature of whale life. If acoustic communication is disturbed enough, the whale may decide to commit suicide.

Sounds travel long distances in water. As a result, whales can communicate with their mates tens of kilometres away. This is the way they find partners for reproduction, inform of good food sources etc. Ships and motorboats make a lot of noise in the oceans. The noise levels may disturb whale communication. And the sea traffic has become more intensive and noisier in the recent past disturbing the whales more and more.

Kommentoi kirjoitusta. Avainsanat: noise pollution, climate change, ship traffic