Every year, dozens of cetaceans and Whales stranded on coasts around the world. This phenomenon is intensively studied, but remains a great enigma for science. The reasons and hypotheses proposed by researchers vary according to the species, the coasts, and even the climate. These strandings can affect a single individual, but can also involve entire groups.
Mass vs. individual strandings
There are two types of strandings main: massive and individual. In the mass strandings, up to hundreds of whales strand together, as has happened off the coasts of Tasmania and New Zealand. The species most affected by such incidents are pilot whales and sperm whales. Places such as New Zealand, Western Australia and Patagonia are tragically known for such events.
On the other hand, individual strandings, which are more common, usually affect baleen whales, such as humpback whales or gray whales. A recent case in Australia revealed a worrying increase in the number of young humpback whales stranded due to malnutrition, which has alarmed the scientific community.
The causes behind whale stranding
Studies have not reached a definitive conclusion on a single reason why whales run agroundHowever, multiple causes have been identified that may influence these incidents, including:
- Natural disorientation: Many whales, especially pilot whales and sperm whales, depend on the echolocation for navigation. However, in areas with shallow coasts or semicircular bays, their orientation system fails due to the lack of a clear sound rebound.
- Geomagnetic factors: Whales, like some migratory birds, are guided by the Earth's magnetic field. Variations in this field, such as those caused by solar storms, could seriously disrupt their navigational ability, leading the cetaceans to unsuitable places.
- Underwater noise: Noise generated by human activities, such as military sonar or oil drilling, can interfere with whale communication and orientation. These loud noises are especially damaging to deep-water species, such as beaked whales. Mass strandings have been documented following military manoeuvres in regions such as Cyprus or the Canary Islands.
- Malnutrition: Overfishing and climate change are severely reducing whales' food reserves, such as krill. This has led to an increase in malnutrition, especially in young whales.
Ultimately, whale strandings are often the result of a combination of natural and human factors.
Impact of climate change
El climate change is another of the causes that scientists consider key in the increase in strandings. For example, the loss of sea ice in the Arctic has reduced the availability of key prey such as amphipods, vital for species like gray whales. Between 2019 and 2023, more than 680 gray whales were counted stranded in the North American Pacific, which shows the seriousness of the situation.
This decline in food availability not only affects the nutritional status of whales, but can also alter their migratory routes, making them more likely to run aground near the coast. The long-term consequences of climate change continue to be seen in the behavior and subsistence of these species.
The social behavior of whales
The Whales are very social animals They usually travel in groups led by one or more individuals. In the case of sperm whales, males take on this role, while killer whales follow a matriarch. If the group leader becomes disoriented for some reason or falls ill, the entire group can follow him to the coast and become stranded.
In some instances, when whales are refloated, they have been shown to return to shore if they hear calls for help from other members of the group. This factor can considerably complicate rescue efforts.
Human interventions: help or harm?
The human interventions They have saved many stranded whales, but rescues are not always successful. Rescue teams work exhaustively to keep the cetaceans hydrated and in good condition, but the damage they suffer out of the water is often irreversible. The immense pressure on their own bodies and dehydration are determining factors in their health.
There are also times when refloating a whale without a prior assessment of its condition can be counterproductive. Some animals are so sick or weak that returning them to the water will prolong their suffering rather than help them. In these cases, experts may recommend euthanasia as the most compassionate option.
However, not everything is bleak. In many countries, emergency hotlines and protocols have been set up to quickly mobilise teams of volunteers and experts, saving the lives of numerous cetaceans. Each rescue operation also provides a unique opportunity to study these animals and learn more about their lives, threats and biology.
Whale strandings are a highly complex phenomenon involving a number of natural and human factors. Further research is needed to better understand their causes and prevent devastating consequences for these species. Cooperation between scientists, rescuers and coastal communities remains essential to mitigate the effects of these incidents in the future.
It's good
The axis of rotation of the earth has changed. Cetaceans and fish are guided by the sun this phenomenon is also happening in the Mediterranean. If the central axis at the north pole was closer to Canada, you will be in Russia in a few years.