Plight of the whale shark: Largest fish on the planet is under threat from extinction

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Plastic pollution in waters around the remote British island of St Helena is putting one of the largest fish on the planet at greater risk of extinction.  This image shows plastic pollution that has washed up on the island


Plastic pollution in waters around the remote British island of St Helena is putting one of the largest fish on the planet at greater risk of extinction.

Whale sharks, which are already listed as an endangered species, pass through the  island’s water as they migrate from November to June.

The volcanic island lies about midway between South America and Africa in the South Atlantic Ocean, thousands of miles from it’s nearest neighbour.

But it is plagued with plastic rubbish that washes ashore from neighbouring continents.

Experts have warned that filter-feeding whale sharks are threatened because they mistake plastic particles in the water for plankton. 

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Plastic pollution in waters around the remote British island of St Helena is putting one of the largest fish on the planet at greater risk of extinction.  This image shows plastic pollution that has washed up on the island

 Whale sharks, which are already listed as an endangered species, pass through the island's water as they migrate from November to June (stock image)

 Whale sharks, which are already listed as an endangered species, pass through the island’s water as they migrate from November to June (stock image)

Experts from the British Antarctic Survey (BAS) say that marine debris on beaches has increased more than ‘ten fold’ in the past decade. 

One plastic item was found every ten feet (three metres) on the island’s black volcanic beaches back in 2003. 

Ecologists now say that they are finding hundreds of items in the same area, with more and more plastic washing up on shore with every tide.

Dr David Barnes from the BAS told The Telegraph: ‘There has been an absolutely dramatic change in St Helena. There are unbelievable levels of change and it’s happened in our lifetime.

‘The animals that eat plankton and smaller algae are not discriminating between microplastics and their food. 

‘They can process the natural food but the microplastics stay in their stomach and build up until they have a stomach full of plastic which, in some circumstances, can weigh more than the actual organism and then they will die.’  

The remote island only has a population of around 4,500 people. Despite its isolated location, St Helena is now plagued with plastic rubbish which washes in from its neighbouring continents

The remote island only has a population of around 4,500 people. Despite its isolated location, St Helena is now plagued with plastic rubbish which washes in from its neighbouring continents

Last year, the island received £72,000 in funding from the UK Government to monitor plastic pollution and establish a recycling programme for waste. This image shows volunteers from the St Helena National Trust collecting rubbish

Last year, the island received £72,000 in funding from the UK Government to monitor plastic pollution and establish a recycling programme for waste. This image shows volunteers from the St Helena National Trust collecting rubbish

Around 125 flip–flops and shoes were collected by the volunteers during a beach clean-up on St Helena along with more than 1,000 plastic bottles, 1,540 pieces of polystyrene, 50 fishing buoys/floats

Around 125 flip–flops and shoes were collected by the volunteers during a beach clean-up on St Helena along with more than 1,000 plastic bottles, 1,540 pieces of polystyrene, 50 fishing buoys/floats

Whale sharks are listed as endangered by the International Union for the Conservation of Nature due to the impacts of fisheries and vessel collisions.

The reduction in sightings has placed them in a vulnerable situation. According to information of 2016, there are about 7,100 whale sharks in the ocean.

Experts have warned that they are even more at risk because they are filter feeders mainly feeding on plankton in huge gulps, ingesting microplastics and larger pieces of plastic instead.

Microplastics cause significant issues for marine organisms, including inflammation, reduced feeding and weight-loss. 

HOW DO MICROPLASTICS GET INTO THE OCEANS FROM RIVERS?

Urban flooding is causing microplastics to be flushed into our oceans even faster than thought, according to scientists looking at pollution in rivers.

Waterways in Greater Manchester are now so heavily contaminated by microplastics that particles are found in every sample – including even the smallest streams.

This pollution is a major contributor to contamination in the oceans, researchers found as part of the first detailed catchment-wide study anywhere in the world.

This debris – including microbeads and microfibres – are toxic to ecosystems.

Scientists tested 40 sites around Manchester and found every waterway contained these small toxic particles.

Microplastics are very small pieces of plastic debris including microbeads, microfibres and plastic fragments.

It has long been known they enter river systems from multiple sources including industrial effluent, storm water drains and domestic wastewater.

However, although around 90 per cent of microplastic contamination in the oceans is thought to originate from land, not much is known about their movements.

Most rivers examined had around 517,000 plastic particles per square metre, according to researchers from the University of Manchester who carried out the detailed study.

Following a period of major flooding, the researchers re-sampled at all of the sites.

They found levels of contamination had fallen at the majority of them, and the flooding had removed about 70 per cent of the microplastics stored on the river beds.

This demonstrates that flood events can transfer large quantities of microplastics from urban river to the oceans.

Microplastic contamination may also spread from organism to organism when prey is eaten by predators.  

Larger pieces have been found in the intestines of whales and seabirds, where they are thought to be potentially fatal and can pierce stomach linings and block digestive systems.

Beth Taylor from the St Helena National Trust told the Telegraph: ‘Given the remoteness of St Helena, if there are still plastics washing up from other places, it shows how huge a global issue it is and it does need to be highlighted.

‘It’s unfair that St Helena gets plastics from other countries but it’s not the only place that suffers from that – back in the UK you’ll get things washing up on the shore.

‘The message from St Helena is, if an island community of just under 5,000 can really roll up their sleeves and make a difference with plastic collection, reuse and recycling, then there’s absolutely no reason why people living in cities with access to all sorts of facilities can’t do the same.’

Plastic pollution in the South Atlantic Ocean could threaten St Helena’s ‘huge array of fish and marine life,’ along with coral ecosystems, according to Defra. 

Last June, the St Helena National Trust Marine Team and the St Helena Government Marine Section walked to Sharks Valley on the island for a beach clean-up.

‘More than 1,000 plastic bottles, 1,540 pieces of polystyrene, 50 fishing buoys/floats and 124 flip–flops and shoes were collected by the volunteers,’ Defra reported.

The whale sharks inhabit St Helena’s waters from November to June, as they migrate across the South Atlantic. The tiny  island which lies about midway between South America and Africa

The whale sharks inhabit St Helena’s waters from November to June, as they migrate across the South Atlantic. The tiny island which lies about midway between South America and Africa



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