Deadly mutating virus blamed for mass dolphin strandings


Animal conservationists are concerned that large rising numbers of dolphins being stranded on the coasts of Spain are caused by a deadly virus that mutates like the coronavirus.

Dolphin strandings have increased dramatically in south-eastern Spain since the beginning of the year and the experts believe that they are dying because of a virus that is affecting their immune systems.

Every single day since 15th January 2021, they have recorded the death of a dolphin on the coast of Almeria province, in south-eastern Spain, which means that more than 20 dolphins have died so far.

It is a high number of dolphin strandings, as the average is usually around 50 per year. The last one took place yesterday, on 11th February, on the coast of Almeria, where a striped dolphin was helped by animal organisation workers to go back to the sea, but their effort was in vain as it died a short while later.

Eva Maria Moron, 48, coordinator of the animal organisation Equinac, said that ‘it is not normal to have such a high number of dead animals in such a short period of time’.

Sixteen of those animals are striped dolphins (Stenella coeruleoalba), whose main physical characteristic is the dark blue line from their eye to their flipper and they tend to avoid human contact. The rest are common bottlenose dolphins (Tursiops truncatus), very well known in the area as they like to swim behind boats and other vessels.

However, the dead dolphins have something different about them compared to the ones recorded last year. Most of them displayed injuries consistent with an interaction with a fishing vessel, such as becoming trapped in fishing nets or colliding with the boats.

Moron explained that ‘those dolphins are arriving to the seashore with empty stomachs and with some symptoms linked with problems in the general nerve system that makes them lose orientation’.

This health condition could be linked with two different causes that could be also happening together. The expert suspects that these symptoms could be linked with a special virus called morbillivirus, that affects cetaceans, especially those with weakened immune systems.

But this theory still needs to be confirmed and therefore organ samples have been sent to laboratories thanks to the cooperation with the General direction of Biodiversity, Forests and Desertification, which is part of the Ministry for Ecological Transition and Demographic Challenge.

The expert also said that the problem with this virus is that it is lethal for the dolphins and it mutates, like the coronavirus. In fact, in 1990, a morbillivirus outbreak killed more than 1,000 striped dolphins in the south-eastern coast of Spain and two more outbreaks were detected in 2007 and 2011.

The symptoms are always the same, the animals seen stranded on the beach were suffering from health conditions linked with their immune system, such as pneumony or encephalitis.

The second cause is dolphins becoming trapped in fishing nets, but this could be also happening due to the virus, as they become disoriented. Moron added: ‘Both causes could be linked.’

According to Moron, the fact that the virus could be affecting the dolphins could be also linked with metals polluting the sea, such as mercury. She added: ‚ÄúThis metal pollution in the sea is causing immunosuppression and the virus affects those with weak immune systems.” She said that this in turn makes them more susceptible to the virus.

According to Moron, the sea is being polluted with metals and this is caused by human activity, because the chemical industry is discarding tonnes of waste directly into the sea. Other causes are the fuel used by boats. She said: ‘You only have to go to the port of any city and you will see how the water is covered in oil, that is the pollution caused by boats and other problems.’

There are other problems linked with the health conditions of the animals, such as overfishing, climate change and the high temperatures of the water and treatment systems discharging untreated waste material into the sea. Moron said: ‘for the most part, climate change is being sped up by human activity.’

The expert also said that the morbillivirus, in its current state, cannot affect humans. The results of the analysis will be released in the following days.