Squat lobsters, bright red sea toads and deep-sea dragon fish were among more than 160 species never previously seen in the region that were spotted on a recent expedition exploring an underwater mountain range off the coast of South America. Researchers from the California-based Schmidt Ocean Institute believe that at least 50 of those species are likely to be new to science.

Underwater mountain ranges are oases of life and biodiversity, where communities of different organisms band together: some creatures make the most of the elevation and unique currents that the peaks provide, while others find refuge in the nooks and crannies of the rocky slopes to build intricate structures.

Erin Easton, of the University of Texas Rio Grande Valley, was the chief scientist on the 40-day research voyage along the Salas y Gómez ridge, which spans the waters from Chile to Rapa Nui, also known as Easter Island. “We’re still astounded by what we observed,” she says.

It’s a political earthquake! The common earthworm, the soil-maker, food provider and grand recycler, is the landslide winner of the inaugural UK invertebrate of the year competition.

Lumbricus terrestris, also known as the lob worm, dew worm and nightcrawler, took a mighty 38% of the popular vote after readers nominated it to be added to the shortlist for the Guardian contest.

The rare and endangered shrill carder bee demonstrated the popular affection for bumblebees by coming second with 15% of the vote while the romantics’ choice, the glowworm, narrowly beat the unexpectedly popular distinguished jumping spider into bronze medal position with 9% of the vote.

Chris Packham, whose plea for the disrupter of the shortlist, the Asian or yellow-legged hornet made the front page of the Daily Star, said: “Through constant wriggling and extraordinary ecological commitment it’s great to see the earthworm take top spot. Although I suspect vote rigging by blackbirds, badgers and moles.”

The nature writer and campaigner Dr Amy-Jane Beer said: “Stop the press, here’s an award that really means something! In a media obsessed with the rare and beautiful, for the overwhelming importance of a cold, slimy, mostly unseen creature long associated with a kind of mute, spineless, humility to receive public recognition is a big deal.”

The invertebrate charity Buglife also welcomed the earthworm’s triumph. “It’s great news,” said David Smith, Buglife’s advocacy and social change officer. “These ecosystem engineers go about their lives often unnoticed yet are vital for producing the food we eat and easing the impacts of flooding. Unfortunately, earthworms are under threat from multiple sources including chemical use, invasive species, and intensive land use, hopefully with its new title, the public will support these vital invertebrates and take action to help them thrive.”

“A man may fish with the worm that hath eat of a king, and eat of the fish that hath fed of that worm,” declared Hamlet, baffling Claudius the King in Shakespeare’s play but hailing the recycling prowess of the earthworm.

Earthworms can bring 40 tonnes of soil to the surface per hectare a year in Britain. Their usefulness is increasingly hailed in an era where regenerative farmers and many others are paying new attention to soil health.

Worms make soils less prone to flooding in winter and less baking hard in summer, they boost microbial activity and, of course, are vital in supporting plant growth, including the crops that feed us.

As well as being important, earthworms lead long (up to six years in captivity) and wondrous lives, and their charisma is well appreciated by those great connoisseurs of the living world, children. One of many readers who nominated the earthworm was Lily, four, who appreciated their “soft” feel in the hand and their general wiggly appeal.

The common earthworm appears on the surface – especially during damp and wet times, hence its other names, dew worm and rain worm – and is one of those precious invertebrates who we can see almost daily, and help too. I always feel better about myself if I stop mid-stride and rescue a stranded worm from the pavement or road.

Unfortunately, like so many other common invertebrates, earthworms are disappearing: the UK’s first national assessment, in 2023, found that populations are estimated to have declined by a third over the past 25 years.

It is not just on farmland where declines are occurring, probably due to pesticides and intensive ploughing, but in broadleaved woodlands – suggesting that wider factors such as climate change and pollution from animal worming including treatments for pets are driving losses.

Surprisingly the most traditionally beautiful animals on the shortlist, the swallowtail butterfly and the Clifden nonpareil moth, polled modestly, finishing in sixth and 10th place respectively.

The naturalist and author Dominic Couzens said: “There’s no doubt that the earthworm is a worthy winner, but perhaps that reflects the grey sky of our troubled times? Perhaps one day we will go with a feelgood selection, such as the sumptuously glamorous Clifton nonpareil or swallowtail?”

Bringing up the rear on the shortlist with just 0.8% of the vote was the Asian or yellow-legged hornet, an invasive species known for attacking honeybee colonies which was nevertheless championed by Packham, who made the case for tackling the biodiversity crisis rather than scapegoating one species, which humans are to blame for spreading.

Europe removed a record number of dams and other barriers from its rivers in 2023, a report has found, helping to restore its disturbed waterways to their natural states.

Nearly 500 barriers were taken out of European rivers last year, according to figures compiled by Dam Removal Europe, an increase of 50% from the year before.

France led the way in helping rivers recover, with 156 removals, the report found, followed by Spain, Sweden and Denmark. The UK removed 36 barriers.

“It is amazing to witness another record-breaking year for dam removals in European rivers,” said Herman Wanningen, the director of the World Fish Migration Foundation and co-founder of Dam Removal Europe.

Europe’s rivers have been fragmented by dams, weirs, culverts and fords – many of which are no longer needed. An estimated 150,000 of the 1.2m barriers in European waterways are obsolete and possibly dangerous, according to the report, which documented 113 deaths involving river barriers in Europe since 2000.

Dam Removal Europe, a coalition of seven environmental groups including WWF and The Nature Conservancy, which aims to restore the free-flowing state of rivers and streams, said the pace of removals was rising.

It highlighted the removal of a quarry weir in Scotland, where a steep gorge blocked heavy machinery and meant the weir had to be removed by hand, along with the removal of a series of dams on the Hiitolanjoki River in Finland, where 34 miles (54km) of river has been opened up to salmon after being blocked for more than a century.

The EU’s proposed nature restoration law – the fate of which hangs in the balance after last-minute lobbying from member states – aims to reconnect 25,000km of fragmented river by 2030. But achieving this “will require a paradigm shift in river restoration”, according to a study in Nature that highlighted the “widespread impacts” caused by small barriers. Although large dams get the most attention, the researchers found that nine in 10 European river barriers are less than 5 metres high.

Connecting rivers helps wildlife travel and allows migratory fish to reach breeding grounds. Removing dams also allows water levels to vary over the year, which can cause habitat changes that increase the diversity of plants and animals, said Pol Huguet, a city councillor in the Spanish town of Manresa, whichremoved a dam as part of a rewilding project. He said: “Thanks to this change, for the first time, we have seen some fish going upstream to this part of the river.”

Dam removals are not always popular. When Poland removed its first big dam in 2021, most people in the area objected despite risks to their safety due to poor construction, a study found in February.

As carbon pollution heats the planet, allowing air to hold more moisture, the risks of extreme rainfall collapsing ageing river barriers is rising. At least three river barriers collapsed last year due to heavy rain in Norway, Northern Ireland, and Slovenia, the report found. Last week, a dam burst in the Orsk region of Russia as heavy rains flooded the area and forced more than 100,000 people across Russia and Kazakhstan to flee.

Obsolete barriers that were built to cope with different climates harmed the river and increased nature loss, said Wanningen. “It’s time to rethink the way we manage our rivers by removing all obsolete barriers and letting as many rivers as possible flow freely. A river that does not flow freely is slowly dying.”