What makes whales and dolphins go ashore and actually deprive oneself of life.
February 10, 2017 on the coast of the South Island of New Zealand Emissions 416 dolphins. They did not float away when the tide began, continuing to slowly die. Volunteers nearby were trying to help mammals by drenching them from buckets, but only a few were saved. This incident has become one of the most notorious such cases in the past decade, and once again raised an exciting question: what is pushing whales and other mammals to such a tragic way to die.
Situation in New Zealand
On the morning of February 10, something made 416 grind (of mammals from the dolphin family) throw itself onto the Farewell shore on the South Island of New Zealand. This was not a novelty for the coast: from November 2012 to the present , about 680 cetaceans died in this place , despite the efforts that local volunteers made to save mammals. Scientists believe that too large a stranded in this place creates to him the reputation of a “cemetery” for cetaceans.
When the mammals were washed ashore on February 10, about 70% died immediately. The remaining 100 grind gave signs of life, lying on the sand in anticipation of death. Local doctors and volunteers rushed to rescue mammals, drenching them from buckets and basins, simultaneously reflecting on the tragedy of the situation. In a conversation with The Guardian journalist resident in New Zealand, Peter Wiles (Peter Wiles) wistfully said that he had never seen a more depressing sight.
Many came to rescue the grind thanks to the warning of the authorities: in the morning they asked people to temporarily suspend work and study in order to help rescue the mammals. Perhaps thanks to this, 100 animals were saved. However, by the next tide, 90 rescuers rushed back to the shore, and more than 500 volunteers were identified to maintain them in a stable condition. They will try again to release into the sea with a morning tide on February 11.
However, it is not a fact that the efforts of volunteers will help. According to Andrew Lamason, an employee of the Department of Conservation, whales and dolphins are social creatures, they are accustomed to move behind a flock, most of which now lies dead on the beach. If they do not find a new leader, then perhaps they will not cease to be thrown ashore until they die.
An operation to clean the dead on February 10 has not yet taken place: the authorities decided to focus on the still living mammals. C 1840 more than 5 thousand whales and dolphins were thrown on the shores of New Zealand. And although in 85% of cases on land there are between one and two mammals, many residents of the country have experience in saving cetaceans from death.
Help on the phenomenon
About 2,000 cetaceans are thrown onto beaches around the world each year. This strange and sad phenomenon occurred for many years before the formation of a modern, emitting smoke and dumping human waste into the sea. Even the Greek philosopher Aristotle, in his scientific works, studied why cetaceans are cast ashore. However, he did not find an exhaustive explanation.
In 2014, British archaeologists found evidence that cetaceans were thrown onto the land about five million years ago, and the first actually recorded case occurred in 1532 in Denmark. And although the direct connection of human activity on Earth with the ejection of cetaceans has not been proven, the frequency of such incidents is increasing.
In the UK, from 1990 to 2010, the frequency of emissions of whales to the coast increased by 25%. During 2013, Scotland recorded 211 cases in which cetaceans or dolphins found themselves on land. In the United States from 2001 to 2009, on the shore of emissions , about 51 thousand of cetaceans. And although there are about 35 institutions in the country aimed at rescuing mammals that have been cast ashore, many cannot be saved.
Since the bodies of dead whales on land quickly rot, threatening the environment and human health, they are usually pushed back into the sea, where carcasses dissolve in natural conditions.
If the body is too heavy, it is lifted with the help of a crane and subsequently buried. However, there are quite tough alternatives, when the carcasses are pushed to the maximum distance in the sea, and then they undermine the explosives already laid in the inside. This way of getting rid of dead mammals is allowed in South Africa, Iceland, Australia and in the state of Oregon in the USA, but sometimes it has terrible consequences . In rare cases, the body is burned.
Scientists have not agreed on why cetaceans are cast ashore. However, there are options that for many years of research entrenched as the main, but unconfirmed theory.
In 2005, British scientist Karen Evans, together with experts from the University of Tasmania, found an interesting detail: over the past 82 years, the frequency of throwing whales in the southern part of Australia and Tasmania increased during changes in the wind.
It was assumed that a sharp change of winds towards the coast knocked the whales off the course and led directly to death on land. Changes in winds could also cause a storm, followed by strong waves driving the whales into dangerous areas.
There are other factors that confirm the influence of navigation on the fate of whales. For example, mammals may accidentally approach the shore in an attempt to escape from predators, often killer whales. Also, scientists note that sandy beaches are not reflected by the whale sonar, forcing them to think that they are deep under water.
Proponents of the theory that the problems of navigation are the main cause of the ejection of whales, note the influence of sonars on ships. According to some experts, locators created by people make the loudest sounds under water, which causes disorientation in whales, and in rare cases – bleeding from the ears.
For example, in 2000, 17 cetaceans with a pronounced bleeding from the ears erupted on the coast of the Bahamas. Later, representatives of the US Navy admitted that it was their fault, as they checked the sonars in the area.
Officially, the US Navy no longer conduct sonar tests in areas of increased whale activity.
Injuries or illness
Even a slight poisoning or injury can knock a whale off course and lead to the fact that it will be thrown onto the land, according to many scientists and specialists in the field of mammals. An example is often given by the fact that many whales die before they are ashore. It happened in February 2017 in New Zealand.
According to experts, this may be a sign that the flock has consumed harmful or poisoned substances – for example, garbage dumped from ships. There is also a serious impact of oil pollution. Even if the whale pack itself does not get into the area of pollution, it can eat fish or algae that have received a dose of toxins. As a result, mammals get sick and weaken.
In 2015, the ecologist of the University of California at Santa Barbara, Douglas McCauley , claimed that humanity inflicts enormous damage on the natural world and on its offspring, including the whales. For example, environmental pollution leads to the fact that fish and mammals have to migrate to unknown territories, risking to become a victim of predators.
There is a hypothesis for the authorship of Australian scientists. From it followsthat there are viruses that adversely affect the hearing aid of marine mammals, because of which the latter start meningitis, encephalitis, and damage to the echolocation system.
As a result, the animals lose their spatial orientation and the ability to move, and then simply suffocate. It is assumed that, throwing themselves onto the shore, the whales are trying to ease their breathing.
Whales are social creatures living in flocks. And where there is a pack, there must be a leader. That is why there is a theory that whales are cast ashore after their leader, and not for other reasons. For example, if the leader of a group gets sick or weakens , this will affect the behavior of the pack, making it less manageable.
In 2012, a group of whales erupted on the coast of Scotland, among which was an elderly one. Then the scientists suggested that if this whale was a leader, then he could lead his flock to death due to aging.
Attachment to the leader, according to some scientists, brings mammals to extremes. For example, if the leader dies on land, the surviving whales only rarely swim away, and are not re-thrown onto the shore where their leader is.
However, not only the leader can lead the group into a trap. There is a chance that several whales will fall ill and weaken to such an extent that they will later be brought to shore. In such cases, the mammals send a “distress signal” to the comrades, on whose call the flock responds. Not realizing that this will lead to her death.
Updated : In the English media, animals were called “whales”, which translates as “whales”. In fact, the dead mammals were dolphins, not whales, or rather, the grindas were black dolphins from the common dolphin family, in English they are called “pilot whale”, which is why the translation error was made.