Fire ants and skin-burning plants are expected to invade Britain’s shores as climate change brings more extreme weather to the UK.

Nature groups, including The Rivers Trust, Plantlife and Buglife, are calling on the Government to do more to stop a “flood of new nature invaders arriving and spreading” across the country.

Over the past 18 months England has experienced its wettest period since records began in 1836. At the same time, 2022 was the UK’s hottest year on record, while a number of heat records were also broken last year, including the hottest ever June and September.

Nature groups warn the wetter and warmer weather is likely to lead to a surge in new species that thrive in these conditions, some of which are known to cause economic damage, harm to people, and declines in already struggling native species.

These include Giant Hogweed, with sap that can burn skin, and the Red Imported Fire Ant, which carries a venomous sting.

David Smith, Social Change and Advocacy Officer at Buglife, said some of the issues nature groups are already seeing include “earthworms being predated by non-native flatworms to American Signal Crayfish damaging riverbanks and undermining flood defences”.

Erin Shott, Communications and Policy Officer at Plantlife, said many invasive plants, such as rhododendron ponticum and himalayan balsam, were first introduced for “aesthetic value” but “are now having a dire impact on native British wildlife”, particularly in temperate rainforests.

The ‘nature invaders’ coming to Britain’s shores

Britain is already home to a number of invasive species that thrive in wet conditions, including:

• Japanese Knotweed. Every homeowner’s worst nightmare, Japanese Knotweed can cause damage to buildings and leaves native plants struggling for space and light. It is known to spread to new locations during flooding.
• Himalayan Balsam. Introduced to the UK in the 19th Century, the weed is a particular problem on river banks, where it spreads quickly at the expense of native flowers. The plant also increases flood risk by leaving large areas of eroded exposed banks when it dies in the winter. It’s also easily dispersed to other areas during flooding.
• Giant Hogweed. Also known to spread across river banks, Giant Hogweed can cause burns to people’s skins and reduce native plant populations
• Zebra Mussels. Originating from the lakes of Russia and Ukraine, these mussels were first spotted in the UK in the 1800s and are believed to have travelled over on the hull of ships. Research by the University of Cambridge has previously found that these non-native molluscs clog up water pipes, costing water companies millions per year in damage. Experts have warned that flooding is causing the invaders to spread to new waterways.
• Chinese Mystery Snail. These large freshwater snails have been discovered in recent years in Sussex and Hampshire. In the US they have been found to carry parasites and diseases.

Other invasive species has been discovered in Europe and are feared to be making their way to the UK:

• Red Imported Fire Ant. An established colony of what experts described as one of the most damaging invasive species was first spotted in Europe in Italy last year. It is feared they could arrive in the UK via contaminated plant or cargo ship. The insects, which are known to travel via floodwater, have a range of negative impacts, including on ground-nesting birds, buildings and public health.
• Golden Apple Snail. A ban on importing the eye-catching mollusc for aquariums was lifted in 2021, but there are fears a warming climate could increase the risk of it establishing in the wild. They are listed as one of the top 100 most invasive species in the world, largely due to their impact on crops

The charities warn that recent extreme weather in the UK is also hampering existing efforts to control invasive species.

For example, heavy rain and flooding earlier this year thwarted attempts by conservationists to trap American mink: predatory mammals blamed for the decline of native species such as water voles.

Heavy rainfall has also led to increased growth of some invasive plants, such as Japanese Knotweed.

Nature groups warned that low budgets and uncertain funding is leaving local groups with reduced capacity to control the spread of invasive species.

Dr Rob Collins, Director of Policy and Science at The Rivers Trust, said invasive plants are “growing faster than ever” and “local Trusts across the country struggling to keep a wave of invasive species at bay”.

How flooding is hampering the eradication of the American mink

After escaping Scottish fur farms in the late 1930s, American mink have spread across most of the UK, preying on native species such as water voles and ground nesting birds.

Once a regular feature on British waterways, water voles have declined by 96 per cent since 1950, largely due to American mink.

Conservationists in East Anglia have used hundreds of “smart trapping” devices to drastically reduce the mink population. Cage traps are placed in tunnels on rafts, with remote monitoring telling conservationists when a trap has been activated.

However, the work has been hampered this year due to flooding, which has made it difficult to reach some of the rafts, while some have been overturned.

Simon Baker, Vice Chair at Waterlife Recovery Trust, which has been running the project, said their work has been “battered by this winter’s persistent rain and flooding”.

“It’s clear that an escalating climate crisis will likely continue to be a challenge but one that will not stop us achieving our objective of a mink free Great Britain,” he said.

They have made a number of recommendations for the next Government to tackle invasive species, including long term funding for local groups to create a “biosecurity citizens army”.

Politicians should also triple the invasive species biosecurity budget to £3 million and provide a further £3 million to fund a permanent dedicated Invasive Species Inspectorate, the nature experts said.

It comes after leaders of four leading nature charities, the National Trust, RSPB, The Wildlife Trusts and Woodland Trust, sounded the alarm over the declining state of the UK’s nature.

The Government was contacted for comment.

In a joint op-ed for i, the CEOs said the UK had become “one of the most nature-depleted countries in the world” and criticised politicians for failing to do enough to reduce biodiversity decline.

Since 1970, UK species have declined by 19 per cent on average, with one in six species currently at risk of extinction, according to a landmark report published last year by the Government in collaboration with non-governmental organisations.