First seals, now a sea horse - but is this a sign of cleaner water in the Thames, or global warming?

A A A

The discovery of a sea horse in the Thames estuary has been hailed as a sign that what was once the outlet for the dirtiest river in Britain is returning to ecological health.

The discovery of a sea horse in the Thames estuary has been hailed as a sign that what was once the outlet for the dirtiest river in Britain is returning to ecological health.

The short-snouted sea horse, Hippocampus hippocampus, last seen in the estuary nearly 30 years ago, was spotted among the seaweed by a fisherman, Brian Baker, as he hauled in his nets to return to Leigh-on-Sea, Essex.

Measuring no more than 15cm in length, it has now been placed on display at the Southend Sealife Adventure centre, where it is seen as proof of the Thames' new ability to support aquatic life. Some also see it as an indication that the waters are steadily warming.

There are other indications of that trend. Red mullet, once almost unheard of, is becoming increasingly common in the estuary. Anchovies, a stalwart of the Mediterranean, have also been caught, and the river is said to be "alive" with mackerel this summer.

The common European sea bass, once at the northern limit of its range, is so at home that the estuary has become a designated nursery for the breed. Fisherman are also seeing increasing numbers of little egrets off the Essex marshes, once considered an extremely rare visitor.

These new arrivals are finding an hospitable environment. Water quality has been greatly improved by the overhaul of two sewage outlets at Crossends and Beckton. Factories and power stations dotted along the Kent and Essex banks have also cleaned up their act.

David Knapp, of the sealife centre, believes the discovery of the sea horse is dramatic proof of the improving lot of the Thames. The last recorded find was in the gates of a power station in 1976. "The sea horse is extremely sensitive to dirty water and would simply not be here if there was significant pollution," Mr Knapp said.

Mr Baker, 56, has been fishing out of Leigh-on-Sea for 30 years. He works alone on board his trawler, the 22ft (7m) Nyella, specialising in harvesting the estuary's muddy floor for Dover sole. "The water is getting a lot cleaner, but its also getting a lot warmer, despite what the politicians might say," he said yesterday.

Sea horses are typically found in southern waters, such as the Bay of Biscay. They are unique in the animal kingdom in that the female passes the eggs to the male, where they are fertilised in a "marsupial-style" pouch. It is the male that gives birth to live young and couples normally stay faithful for life.

Although it is a fish, it has no scales. Its ringed appearance comes from bony plates and the pattern on the head of each is as individual as a human fingerprint.

While the sea horse has been around for more than 40 million years, it is coming under increasing pressure in its main habitat, coastal tropical and temperate waters. One of the biggest threats comes from its reputation for possessing magical and healing powers, which have made it a popular "cure" in traditional Chinese medicine. Their beauty and behaviour have also made them vulnerable to collectors, with millions living out their lives as aquarium curiosities.

"This is an exciting sighting," said Kelvin Boot, director of the National Marine Aquarium at Plymouth. "These are wonderful, charismatic fish. They are instantly recognisable, may have given rise to the dragon legend and even breathe 'smoke', a soupy exhalation of its food. We still don't really understand their distribution but here they would be on the northern limits of their range."

There are two species of sea horse in Britain, the other being the long-snouted ( Hippocampus guttulatus), normally seen around the Channel Islands and the South-west coast. The Great British Sea Horse Survey, established in 1996, reports increasing numbers.

Yet the cleaner waters that attracted this sea horse are presenting new challenges for fishermen. While a generation ago there were more than 50 boats operating from the Thames estuary ports, now there are fewer than a dozen.

The fishing quota for sole is 110 tonnes a year for the entire North Sea fleet below 10 metres, and Mr Baker says it is not unusual to see more than 20 seals bobbing around in the estuary channels. "Each eats four to
five tonnes of fish a year. It doesn't take many for the entire British quota to be going down their throats. I like to see them about, but there are more and more every year."

NEW ARRIVALS

Red mullet

Growing up to 30cm long, the red mullet is fished for around the Canary Islands, in the Mediterranean and in the Black Sea. The fish are commonly found on the gravel, sand and mud bottoms of the sea.

Common seal

The most common of the pinnipeds (fin-footed mammals), there are about 500,000 worldwide.
Growing to nearly 6ft in length, it tends to stay within 12 miles of shore.

Little egret

Formally listed as a rare breeding species, this small white heron migrated to Britain for the first time in 1989.
A distinctive bird with a long black bill, the little egret is now breeding on south coast sites, where it huntsfish in shallow waters.

Have you tried new the Independent Digital Edition apps?
Life and Style
love + sex
Arts and Entertainment
Victoria Wood, Kayvan Novak, Alexa Chung, Chris Moyles
tvReview: No soggy bottoms, but plenty of other baking disasters on The Great Comic Relief Bake Off
Sport
Ashley Young celebrates the winner for Manchester United against Newcastle
footballNewcastle 0 Man United 1: Last minute strike seals precious victory
Life and Style
Tikka Masala has been overtaken by Jalfrezi as the nation's most popular curry
food + drink
Arts and Entertainment
Seth Rogan is one of America’s most famous pot smokers
filmAmy Pascal resigned after her personal emails were leaked following a cyber-attack sparked by the actor's film The Interview
News
Benjamin Netanyahu and his cartoon bomb – the Israeli PM shows his ‘evidence’
people
Arts and Entertainment
80s trailblazer: comedian Tracey Ullman
tv
News
i100
Life and Style
A statue of the Flemish geographer Gerard Kremer, Geradus Mercator (1512 - 1594) which was unveiled at the Geographical Congree at Anvers. He was the first person to use the word atlas to describe a book of maps.
techThe 16th century cartographer created the atlas
Arts and Entertainment
Stephen Tompkinson is back as DCI Banks
tvReview: Episode one of the new series played it safe, but at least this drama has a winning formula
News
i100
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
iJobs Job Widget
iJobs General

Recruitment Genius: UI / UX Designer

£25000 - £35000 per annum: Recruitment Genius: This firm are focussed on assis...

Recruitment Genius: General Processor

£7 per hour: Recruitment Genius: A vacancy has arisen for a General Processor ...

Recruitment Genius: Outbound Sales Executive - B2B

£18000 - £22000 per annum: Recruitment Genius: A great opportunity has arisen ...

Recruitment Genius: Online Sales and Customer Services Associate

£14000 - £16000 per annum: Recruitment Genius: Full time and Part time positio...

Day In a Page

War with Isis: Iraq's government fights to win back Tikrit from militants - but then what?

Baghdad fights to win back Tikrit from Isis – but then what?

Patrick Cockburn reports from Kirkuk on a conflict which sectarianism has made intractable
Living with Alzheimer's: What is it really like to be diagnosed with early-onset dementia?

What is it like to live with Alzheimer's?

Depicting early-onset Alzheimer's, the film 'Still Alice' had a profound effect on Joy Watson, who lives with the illness. She tells Kate Hilpern how she's coped with the diagnosis
The Internet of Things: Meet the British salesman who gave real-world items a virtual life

Setting in motion the Internet of Things

British salesman Kevin Ashton gave real-world items a virtual life
Election 2015: Latest polling reveals Tories and Labour on course to win the same number of seats - with the SNP holding the balance of power

Election 2015: A dead heat between Mr Bean and Dick Dastardly!

Lord Ashcroft reveals latest polling – and which character voters associate with each leader
Audiences queue up for 'true stories told live' as cult competition The Moth goes global

Cult competition The Moth goes global

The non-profit 'slam storytelling' competition was founded in 1997 by the novelist George Dawes Green and has seen Malcolm Gladwell, Salman Rushdie and Molly Ringwald all take their turn at the mic
Pakistani women come out fighting: A hard-hitting play focuses on female Muslim boxers

Pakistani women come out fighting

Hard-hitting new play 'No Guts, No Heart, No Glory' focuses on female Muslim boxers
Leonora Carrington transcended her stolid background to become an avant garde star

Surreal deal: Leonora Carrington

The artist transcended her stolid background to become an avant garde star
LGBT History Month: Pupils discuss topics from Sappho to same-sex marriage

Education: LGBT History Month

Pupils have been discussing topics from Sappho to same-sex marriage
11 best gel eyeliners

Go bold this season: 11 best gel eyeliners

Use an ink pot eyeliner to go bold on the eyes with this season's feline flicked winged liner
Cricket World Cup 2015: Tournament runs riot to make the event more hit than miss...

Cricket World Cup runs riot to make the event more hit than miss...

The tournament has reached its halfway mark and scores of 300 and amazing catches abound. One thing never changes, though – everyone loves beating England
Katarina Johnson-Thompson: Heptathlete ready to jump at first major title

Katarina Johnson-Thompson: Ready to jump at first major title

After her 2014 was ruined by injury, 21-year-old Briton is leading pentathlete going into this week’s European Indoors. Now she intends to turn form into gold
Syrian conflict is the world's first 'climate change war', say scientists, but it won't be the last one

Climate change key in Syrian conflict

And it will trigger more war in future
How I outwitted the Gestapo

How I outwitted the Gestapo

My life as a Jew in wartime Berlin
The nation's favourite animal revealed

The nation's favourite animal revealed

Women like cuddly creatures whilst men like creepy-crawlies
Is this the way to get young people to vote?

Getting young people to vote

From #VOTESELFISH to Bite the Ballot