Cocaine in rivers harming endangered eels, study finds

Tests show drug causes eels to become hyperactive and damages their muscles, possibly hindering their ability to migrate

Patrick Barkham

Thu 21 Jun 2018 16.54 BSTLast modified on Thu 21 Jun 2018 19.30 BST

Tiny amounts of cocaine flushed into rivers cause eels to become not only hyperactive but to suffer from muscle wastage, impaired gills and hormonal changes, a study has found.

The impact of traces of cocaine on the physiology of European eels could be hindering their epic migrations through the oceans to reproduce, according to researchers who examined the impact of the drug.

The tiny concentrations of cocaine in the laboratory tests are equivalent to the trace levels found in rivers and water systems from illegal drug use, particularly near major cities.

Eels were exposed to 20 billionths of a gram of cocaine per litre (20ng/l) of water for 50 days. The cocaine-exposed eels appeared “hyperactive” and their skeletal muscle showed evidence of serious injury, including muscle breakdown and swelling.

Even after going into “rehab” – clean waters – for 10 days the eels were still found to have damaged muscles and increased cortisol levels. This stress hormone can cause fat wastage, and endangered European eels require fat reserves to make a successful migration to the Sargasso Sea in the west Atlantic, where they breed.

“All the tissues affected by cocaine play a key role in the fish survival,” said Anna Capaldo of the University of Naples Federico II and the lead author of the study, published in Science of the Total Environment.

 “It is likely that the eels exposed to cocaine have a reduced performance. For example, impaired gills could reduce the breathing ability of the eels; a damaged muscle could reduce their swimming ability.”

Continued  

Eels Consume Their Own Bones to Survive Migration

By Charles Q. Choi, Live Science Contributor | October 19, 2016 06:26am ET 

To survive an arduous swim thousands of miles long without eating anything on the way, European eels apparently lose a significant amount of bone in a way that keeps them alive and moving, a new study finds.

This finding could yield insights that will help scientists prevent or reverse human bone loss, the researchers said.

In order to spawn, European eels (Anguilla anguilla) undertake a 3,000-mile-long (5,000 kilometers) migration from European freshwaters across the Atlantic Ocean to the Sargasso Sea, located between the Azores Islands and the Caribbean Sea. During this trek, previous research found that they not only mature sexually, but also abstain entirely from eating. 

During this energy-consuming, months-long journey, eels lose substantial amounts of bone, other research has found. "Their bones become significantly thinner — for instance, their skull loses more than 50 percent of bone volume, while the spine loses about 65 percent of bone volume," said study senior author Björn Busse, a biomedical scientist and biomedical engineer at University Medical Center Hamburg in Germany.

A great deal remains uncertain regarding the specific mechanisms that drive this bone loss in eels. A better understanding of how this bone thinning works could "provide new directions in understanding human bone-loss syndromes," Busse said.

To shed light on how the eel skeleton shrinks as it matures, the scientists analyzed the bones of 30 specimens at different stages of the eel life cycle. Since eel migration takes place in the deep sea, and satellite tags are too big for animals as small as these eels (adults typically reach lengths of about 2.3 feet, or 70 centimeters), the researchers had no way to collect bone samples from actual migrating eels. Instead, they examined eels that were artificially induced in a lab to mature through hormone injections.

Read on 

Eels given paths to help them get around Braunton

By NDJDuncan | Posted: August 05, 2014

EELS are finding it easier to get around Braunton Marshes thanks to a series of “paths” which have been laid out for them.

As part of the Government’s push to increase eel numbers across the UK, the Environment Agency worked with local farmers and the group which maintains Braunton Marshes to improve access for eels.

The recently completed routes are designed to assist elvers – immature eels – on their journey into the marshes’ freshwater where they mature and breed.

It is hoped the project will also help the otters and birds which eat them.

Read more ...

The secret life of the slippery eel

Once they were nearing extinction. Now, down in Somerset, a group of fisherman have assembled to catch a million of them in a single night. What has changed?

Last Monday, an hour after sunset on the Taunton Road in Bridgwater, a cluster of white vans gathered behind the BMW garage. Beside them, a small crowd of fishermen laden with plastic buckets and wooden trays of baby glass eels stood waiting for the night's haul to be weighed. The eels slithered and roiled. High tide and a full moon had brought an extraordinary number to these shores. And on the banks of the River Perrett and the Severn, fishermen and conservationists assembled with the aim of catching a million of the creatures in a single night and – since their migratory route had been blocked by dams, weirs and flood defences – redistributing them further along the river.

The first ever eel conference was held here in 2009. It had been a hard year for eels; numbers had dwindled starkly. Over the past 200 years, we have drained and destroyed 80% of our wetlands, while 25,000 hydropower stations and tens of thousands of unscreened waterpumps across Europe threatened the species further. Early the following year, the Sustainable Eel Group (SEG) was established, and a regulation introduced, requiring each country to devise an eel-protection plan. "In Britain," says Andrew Kerr, chairman of SEG, "we lead in unblocking the eels' migratory pathways."

Continued

Eels to be helped back into Lake Windermere

Critically endangered eels are to be helped back into Lake Windermere, Cumbria, where they have not been seen in significant numbers for 30 years.

The European eel has seen a huge decline, partly because of barriers to migration including dams and weirs on rivers and flood defences.

Two chutes - or "eel passes" - are being put in the River Leven to enable access into England's largest lake.

Conservationists hope to get numbers back to 40% of those seen in the 1980s.

Over the past three decades, there has been a 95% decrease in the number of European eels due to migration barriers as well as overfishing and loss of habitat.

The eels begin their lives in the Sargasso Sea, near Bermuda, before swimming thousands of miles across the Atlantic and heading up UK rivers to grow.

They later make the return journey to spawn.

Read on

Thousands of Dead Eels Wash Ashore in China

Tens of thousands of dead eels have washed ashore in China over the past few weeks.

The eel is just the latest animal to die en masse in China's waters. In March, thousands of dead pigs were dumped by farmers into the Hangpu River in Shanghai, and hundreds of dead ducks and fish have also turned up in Chinese waterways.

Although no one knows the cause yet, some suspect the China National Offshore Oil Company may be responsible, the website Quartz reported. That company is doubling its crude oil production. 

read further

Eel influx heralds new beginning for Dearne

Published on 17/07/2013 08:56

Over 50,000 slippery customers have been welcomed to the Dearne under a plan to boost nature under water at a nature reserve.

An avalanche of eels was released in to the River Dearne at Wombwell’s RSPB Old Moor site, to boost dwindling fish numbers.

Industrial pollution saw eel presence in the river dip by 95 per cent and they became an endangered species.

But the river has been cleaned up and The Don Rivers’ Trust received £92,000 from DEFRA to support the eel re-introductions.

The trust teamed up with the RSPB to identify suitable watery homes for eels, and the Dearne washlands of Old Moor, Bolton Ings and Edderthorpe Flash was found to be ideal.

A number of eel-passes were installed to allow the creatures to make their way up river and past the weirs to breed.

http://www.epworthbells.co.uk/news/isle-news/eel-influx-heralds-new-beginning-for-dearne-1-5861979

Eel migration study reveals porbeagle shark predation in the Gulf of St. Lawrence

Eel migration study reveals that most of them are eaten!

March 2013. A tagging study has revealed that porbeagle sharks in the Gulf of St. Lawrence could severely impact the number of migrating American eels in the region.

Eight eels tagged
Canadian researchers tagged eight adult eels in the St. Lawrence River as part of the Ocean Tracking Network's investigation to uncover the eels' pathway through the Gulf to spawning grounds in the Sargasso Sea- a journey that has mystified scientists for over a century.

Adult eels have never been seen in the Sargasso Sea. The researchers hoped to track their eels right into the Sea to precisely document spawning areas. Eight eels from the St. Lawrence River in Quebec were tagged with satellite "pop-up tags." All eight tags detached from the eels and surfaced prematurely, suggesting the eels' untimely death.

Tags swallowed
Seven tags transmitted data which included swimming depths, times, dates, and sea temperatures. Six tags recorded a sharp and sustained spike in temperature. Water temperatures in the Gulf of St. Lawrence in October range between 0 - 10°C. Tags recorded temperatures of 22 - 28°C-stomach temperatures of warm-bodied pelagic fishes.

Porbeagle predators
The ingested tags continued to record data on the dive patterns and depths of the animal. By comparing the known diving and depth patterns of porbeagle sharks and bluefin tuna to those recorded by the tags, investigators identified porbeagle sharks as the predators.

On March 11, the Convention on International Trade in Endangered Species voted for greater protection of five shark species including porbeagle sharks.

Julian Dodson, professor at Laval University and OTN principal investigator, co-authored the study. "Both species are in trouble, and measures to conserve one may well be at odds with efforts to protect the other. What we really need now are studies to quantify just how important eels are in the diets of sharks and just what impact shark predation has on eel abundance."

113 acoustic tags fitted - 4 survive
In addition to pop-up tags, investigators also fitted an additional 113 eels with acoustic tags. These simpler tags broadcast only their identity and are detected by receivers moored in the ocean. Only four of the 113 eels leaving the Gulf of St. Lawrence for the Atlantic Ocean were detected on the OTN acoustic array in the Cabot Strait. The information suggests that the porbeagle sharks are taking a heavy toll on the migrating eels.

MAP OF THE ESTUARY AND GULF OF ST. LAWRENCE SHOWING RELEASE SITE OF EELS (PURPLE CIRCLES), SHARKS (RED TRIANGLES) AND TUNAS (GREEN POLYGONS) AS WELL AS LOCATION OF FIRST TRANSMISSION OF TAGGED EELS (BLUE CIRCLES).

"We could hope that there will be increased pressure to protect eels in fresh water, particularly during downstream migration through power dams," says Mélanie Beguer-Pon, OTN researcher at Laval University. "We can't do anything about shark predation, but we can limit mortality in turbines."

The study was conducted by Mélanie Beguer-Pon, José Benchetrit and Julian Dodson (OTN, Laval University), with Martin Castonguay (OTN, DFO-IML), Kim Aarestrup (OTN, NIAR-Denmark), Steven Campana (DFO-BIO) and Michael Stokesbury (OTN, Acadia University). Read the full paper here

http://www.wildlifeextra.com/go/news/eel-migration-013.html

Mysterious Eels' Mating Migration Tracked

Rare European eels from the Mediterranean to Scandinavia make an epic journey when it's time to mate. They leave rivers and brackish habitats, swimming hundreds of miles across the Atlantic to the Sargasso Sea, an open ocean region that is warmer, saltier, bluer and clearer than the surrounding waters.

This trek had remained a mystery to science since no eggs or adult eels have ever been caught in the Sargasso Sea. But researchers recently attached satellite tags to about 600 eels from different places in Europe and were finally able to map the route of the spawning fish.

"We could track the satellite tags as far away as the Azores. This suggests that the eels take a different route to the Sargasso Sea than previously thought. It seems as if they’re saving energy by hitching a ride on the Azores Current," researcher Kim Aarestrup, of the Technical University of Denmark, told youris.com.

Continued:  http://www.livescience.com/26201-mysterious-eels-mating-migration-tracked.html

French eel conservation work viewed by Gloucestershire team

Conservationists from Gloucestershire are travelling to France to look at ways of stopping the decline of eels.

The group will see work being carried out in Normandy where two dams on the Selune River are being removed.

The visit is part of a wider campaign to draw attention to river barriers which stop the migratory European eel from reaching its home waters.

It is estimated there are 1,500 river barriers, tidal gates, flap valves and weirs in France.

Dr Gordon McGlone, from the Gloucestershire Wildlife Trust, said he feared the county would lose its elvers and silver eels forever unless UK and European countries take rapid action.

"This once common fish is now in such decline that commercial fisheries are in crisis," he said.

http://www.bbc.co.uk/news/uk-england-gloucestershire-20761800

Huge eels found swimming in the streets after 'weather bomb' hits New Zealand

They are one of the least attractive of all fish species and are normally found lurking in oceans and rivers.

But when part of New Zealand was hit by a 'weather bomb' recently, a number of eels suddenly sprung up in some surprising locations.

Residents in one street in Masterton, Wellington, were left shocked to discover dozens of the slimy creatures swimming in large puddles and gutters in the road.

People could be spotted in the streets attempting to help the eels back into deeper water as a number became stranded on the side of the road.

It follows days of appalling weather in the region.

Read more: http://www.dailymail.co.uk/news/article-2110473/New-Zealand-Huge-eels-swimming-streets-weather-bomb-hits.html#ixzz1od1bcg9p 

Migrating Somerset eels tracked by camera

A high-tech camera is being used to track eels as they begin their migration to the North Atlantic from Somerset.

The acoustic camera has been placed in the Huntspill River to record the number of eels setting off on the 3,000 mile (4.800km) journey to the Sargasso Sea.

Scientists had previously been unable to record eel numbers, the Environment Agency said.

The cameras, which operate by using sound waves, were originally designed to detect cracks on oil rigs.

Environment Agency spokesman Pete Sibley said the introduction of the technology was "our first real chance to record and capture eel numbers by direct observation and increase our understanding of the creature's mysterious life cycle".

The eel population has suffered a 95% decline over the past 30 years as a result of over fishing, pollution and disease, the agency said.

http://www.bbc.co.uk/news/uk-england-somerset-16687544

Trust turns to eels in war against US crayfish

By Nicholas Christian

THE battle against invading American signal crayfish is being stepped up in one of Scotland's biggest lochs.

 

Millions of crayfish have infested picturesque Loch Ken, north of Castle Douglas in Dumfries and Galloway, and efforts to control their numbers have failed.

Now thousands of European eels, which eat crayfish, are being introduced into a river that runs into the loch in the hope that they will reduce the population.

Fishing in the loch, the biggest in the south of Scotland, has been badly hit by the infestation of the American crayfish, costing the region tens of thousands of pounds.

The Galloway Fisheries Trust, which is behind the project to introduce the baby eels, believes that once they are fully grown the eels will leave the River Dee for the loch, where they are expected to devour large numbers of crayfish.

Rownan Armstrong, a biologist with the Galloway Fisheries Trust, said: "The eels are still young and it will take time for them to grow."

The loch and the River Dee used to be home to a healthy population of the eels, but following the construction of Tongland Dam, near Kirkcudbright, the numbers fell dramatically.

But now eels are being trapped below the dam and are being transported above it and placed in small burns in the lower river.

A Scottish Government-backed cull of the invading crayfish resulted in the deaths of two million two years ago, but it has made little impression on the fast-growing American species, which was introduced to the United Kingdom 20 years ago.

http://scotlandonsunday.scotsman.com/nature/Trust-turns-to-eels-in.6850154.jp

Eel swims up man's penis

A Chinese man who tried a beauty treatment for bathing with live eels was left in agony - when one slipped up his penis.

Vain Zhang Nan, 56, had been told bathing with eels would make him look years younger because they nibbled off layers of dead skin.

So he bought ten from a local market, in the city of Honghu, Hubei Province, and decided to give it a try at home.

But one of the 6in long elvers squirmed up his urethra and swam right into his bladder.

He needed a three-hour operation to remove the eel - by which time it was dead.

Zhang said: "I climbed in the bath and could feel the eels nibbling my body, then I felt a severe pain.
"I tried to grab the eel to pull it out again but it was too slippery and disappeared."

Initially, he was too embarrassed to seek help but when the eel didn't reappear naturally he went to the Wuhan People's Hospital.

Doctors used an ultrascan to locate the eel in Zhang's bladder and operated to remove it.

http://web.orange.co.uk/article/quirkies/Eeel_swims_up_mans_penis

France signs death warrant for the eel

Europe's eel populations face being wiped out because France has refused to accept a continent-wide complete ban on the export of glass eels.


European countries are trying to hammer out a deal to allow eel populations to recover – eel numbers have declined by more than 90 per cent in the past 20 years.

Britain has imposed its own temporary ban on fishing for mature eels, and places quotas on the capture of glass eels, the tiny translucent juvenile fish that are born in their millions in the Sargasso Sea and travel to European estuaries to mature into adults.

But demand from China for glass eels has pushed up prices to more than €1,000 (£850) a kilo – similar to cheap caviar – providing fisheries with a major incentive to continue trawling.


Last year, the Convention on International Trade in Endangered Species called on trade in European eels to be controlled. The EU's Scientific Review Group has recommended a complete ban on exports this winter. But at a meeting in Brussels, France – Europe's largest eel exporter – refused to sign up to a ban. The result is that no quota has been set just as the eel season kicks off.

Campaigners are concerned that France will continue to fish eels in unsustainable numbers this winter. French fishermen have threatened to go on strike if a ban is brought in.

Compared to Britain, which accounts for only 2 per cent of Europe's annual eel catch, France is a major exporter of glass eels to Asia and uses mechanised trawlers in the Bay of Biscay to fish for them.

Last year the total Cites-recommended French export quota was 14 tonnes, but campaigning groups that track fishing exports accuse France of shipping more than this to China alone.

"Exploitation of eels by any one member state impacts the region's entire eel population and therefore management purely at the national level makes no sense," said Stephanie von Meibom, the European programme co-ordinator of the conservation group Traffic. "It is inconsistent with EU policy which emphasises harmony, consistency and coherence between member states."

Pollution, climate change and unsustainable fishing practices have led to a 90 per cent drop-off in worldwide eel populations, scientists say.

Although the Japanese usually insist on eating their indigenous eels, the Chinese and Koreans are less fussy and import millions of European glass eels, which are then grown to maturity before being eaten.

Iceland, Norway, Ireland, Holland, Britain and parts of Spain have brought in their own quotas or bans. But the comparatively lax approach by the French authorities has placed pressure on other European fishermen to flout those bans.

Peter Wood, managing director of UK Glass Eels, accused the French of behaving selfishly and of feeding off the sacrifices of other nations. "They do seem very keen in France to continue to export everything to Asia, and that seems to me a huge loss of a valuable resource," he said.

"They've got this idea that they have this resource of glass eels and it is theirs to do with as they see fit. But it's a collective resource. Most of the glass eels came from breeding stock from other European nations. Some have come from comprehensive restocking programmes in the past, like in Northern Ireland and Sweden. Stock from these countries has gone back to the Sargasso Sea to breed."

By Jerome Taylor and Lewis Smith


http://www.independent.co.uk/life-style/food-and-drink/news/france-signs-death-warrant-for-the-eel-2130869.html

Man f-eel-ing blue after op

By STAFF REPORTER
Published: 03 Aug 2010
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A FISHMONGER has told how he nearly died after he slipped into a tank of eels — and one shot straight up his bum.

Horrified Li Chang, 43 — who suffered severe internal injuries — had been sitting on the edge of the tank at his warehouse in Guangzhou, southern China, where the eels were waiting to be cooked.

But he slipped off his perch into the giant tank filled with hundreds of the writhing creatures.

Chang said: "I guess they were scared when I suddenly landed in the tank so they started wriggling everywhere.

"Several shot up my trouser leg. And then to my horror I felt one go up my bottom."

Incredibly Chang was so embarrassed that he carried on working.

He said: "I didn't say anything at first when I climbed out - I was too embarrassed. I dried myself off and tried to carry on working, but it was just too painful."

Colleagues dialled the emergency services when Chang eventually collapsed in agony.

Astonished medics carried out a five hour operation to remove the eel and repair the severe internal trauma caused by it thrashing about.

A hospital spokesman said: "The eel had badly injured the patient. If he had not arrived when he did he would have died. We expect he will make a full recovery though.

"The eel was as wide as two fingers and as long as a man's arm."

Blue ribbon eel snapped in photo contest

Click to enlarge

http://e-edition.metro.co.uk/2010/06/01/ - p21.

Story of the monster of Whitewood Lake (via Paul Cropper)

Story of the monster of Whitewood Lake
28 April 2010
Drogheda Independent
English
(c) 2010 Independent News & Media PLC

Many years ago, while casting a line or two out at Lough Mentrim, I heard the tale of the local 'Loch Ness' monster. Over 40 years ago an eel-like ceature was sighted by Dennis Barnes of Doncaster while fishing on the shores of the deep 10acre Whitewood Lake near Nobber.

'It was raining,' he said at the time, 'but in the area which joins the part of the lake from the River Dee, I saw something turn in the water'. He then witnessed was appeared to be a Conger eel rise fom the water. 'It resembled a smaller version of what has been photographed on a number of occasions in Loch Ness,' Mr Barnes claimed. 'The part protruding from the water seemed to be about nine inches high and two foot long and was dark brown and green. It resembled an eel and although it was near to my bait it didn't bite.

'About 10 seconds later something frightened my son Peter out of the water where he was standing. If it was the same creature it traversed about 100 yards of water in 10 seconds'. If it was an eel, he feels it must have weighed up to 60lbs About 12 years earlier, three local fisherman, Paddy O'Brien of Robertstown, Patrick Finnegan, jun and David McDowell of Boynagh were reported to have seen something similar in the lake.

The Inland Fisheries Trust were asked to investigate the lake and possibly lay nets to try and catch the monster.
Whatever happened to the Whitewood 'monster' can anyone tell me?

Document DROGH00020100428e64s0004m

Thames eel populations crash by 98% in five years, scientists warn

Concerns grow over dramatic drop in numbers of mysterious creatures that migrate across the Atlantic

guardian.co.uk, Thursday 21 January 2010 17.34 GMT

Eel populations in the river Thames have crashed by 98% in just five years, scientists warned today.

The eel, which has been a traditional east London dish for centuries, now appears to be vanishing from the capital's river, according to researchers from the Zoological Society of London (ZSL).

Each year, ZSL's Tidal Thames Conservation Project places eel traps in a number of the river's tributaries, to catch the fish and allow scientists to record numbers before setting them free.

While 1,500 were captured in the traps in 2005, just 50 were recorded last year.

The eels are thought to take up to three years migrating as larvae from the Sargasso Sea to European rivers, where they spend up to 20 years before making the 4,000-mile return journey across the Atlantic to spawn and die.

But conservationists are concerned the species is not returning to the Thames, or is facing problems in the river and its tributaries.

European eels and flounders were the first species to recolonise the Thames estuary after it was considered "biologically dead" in the 1960s, and there are fears the rapid collapse of the eel population could have knock-on effects for other species in the still-fragile ecosystem.

Other rivers in the UK are also seeing declines in eel populations, ZSL said.

Dr Matthew Gollock, tidal Thames conservation project manager, said: "Eels are mysterious creatures at the best of times but we are very concerned about the rapid disappearance in the Thames.

"It is difficult to say what is going on – it could be due to a number of potential factors including changes in oceanic currents due to climate change, man-made structures such as dams and the presence of certain diseases and parasites."

And he said there was a need to find out why the declines were happening, in order to save the eels and help other species in the estuary's food web who would be affected by its disappearance, such as birds which feed on it.

"Time appears to be running out for eels in the river Thames and this could have a domino effect on other species in the Thames," Gollock said.

"The Thames is a very urban, developed estuary. It's much healthier than it was 50 years ago, but there is constant pressure on it.

"It's quite a precarious ecosystem and the fast removal of any species — whether it is a fish or a plant - is going to upset the balance," he said.

http://www.guardian.co.uk/environment/2010/jan/21/eel-thames-population-crash
(Submitted by Tim Chapman)

Mysterious monster lurking beneath British Isle lake captured on video

September 28th, 2009

London, September 28 (ANI): Scientists have got hold of incredible new footage that could shows a mysterious monster lurking beneath one of the deepest lakes in the British Isles, which is unlike any creature ever seen.

According to a report in The Sun, Jonathan Downes spotted the “creature” thrashing around in one of the Lakes of Killarney in County Kerry, Ireland, while on holiday.

His eerie sighting was in the Upper Lake one of three interlinked lakes that make up the area.

The mystery comes just a few years after bizarre unexplained sonar recordings showing a large body were made in the adjoining Muckross Lake.

Along with his wife and friends who also had cameras, Downes, from Crediton, Devon, managed to capture shapes moving across part of the lake.

Downes, who is director at the Centre for Fortean Zoology, said that he had heard of the sonar reading before visiting the lake, but was “ridiculously” lucky to see anything.

“What we saw was a thing about nine to 10ft long. I’d love to say I saw long necks and humps and things but I didn’t,” he said.

Downes, who studies cryptozoology – which investigates unknown species of animals, described seeing what he see described as appearing to be “a long thin eel-like creature appearing about 10ft long”.

“I believe it must be a large eel. It was a pale colour. What I saw didn’t actually really come out on the picture as well,” he said. (ANI)

http://www.sindhtoday.net/news/1/54900.htm

http://blog.taragana.com/n/mysterious-monster-lurking-beneath-british-isle-lake-captured-on-video-180196/