A petition calling for the protection of marshland where the UK's largest theme is set to be built has been signed by more than 20,000 people.

The Save Swanscombe Marshes campaign fighting to designate the area as a site of special scientific interest (SSSI) stepped up today as dozens of ecology experts and campaigners pressed Natural England to grant an application for tougher conservation rules.

Jamie Robins is from Buglife

Conservationists say the case for the Swanscombe Peninsula ­– between Dartford and Gravesend where the proposed £2.5 billion London Resort project would be located – is the strongest case they have ever seen for "SSSI designation and wildlife protection".

The RSPB, Buglife and the Kent Wildlife Trust – along with 77 other representatives from nature organisations and public bodies – have written to Natural England to "urgently consider the evidence and recognise the special interest of the Swanscombe Peninsula".

The petition set up by Buglife five months ago today passed the 20,000 mark.

London Resort Holding Company's (LHRC) application to build a 1,245-acre theme park, hotels and water park and is being dubbed the UK's Disneyland.

Its proposals will be scrutinised by the Planning Inspectorate – the government's planning authority – over the next 18 months to decide whether to grant planning permission through a development consent order (DCO).

But conservation groups say recent surveys show the peninsula is home to more rare and threatened species than any other brownfield site in the country.

Opponents have also claimed LHRC has used outdated environmental assessments in its submissions to the Planning Inspectorate, which will be reviewed by inspectors.

SSSI designation gives protection to important conservation sites and makes it harder for developers to achieve planning permission but does not prevent it entirely.

Strict land management conditions are imposed to ensure the land, rare species and wildlife are protected and Natural England would have to agree to works taking place and planning permission would still be required.

That decision will ultimately come down to the government-appointed planning inspectors and the Secretary of State for Housing, Communities and Local Government.

LHRC says it aims to run the first carbon-neutral theme park and is aiming to leave much of the Peninsula undeveloped and enhance the landscape and integrate it into the park designs. Its proposals include integrating a public rights of way and green network and access to the river Thames for visitors and residents.

But critics say the land should be not be developed at all.

Conservation groups say the Swanscombe Peninsula has "returned to nature over time and rewilded itself" with 250 rare and threatened invertebrate species calling the marshes home.

Along with the critically endangered jumping spider – which can only be found at one other location in Britain – there are a host of other beetles, spiders, bees and rare flora on the site. It is also home to breeding birds such as nightingales and black redstarts and other animals including bats, reptiles and water voles.

Richard Bloor, wilder towns manager at Kent Wildlife Trust, said: “At a time where the UK is seeing a devastating loss of nature and wildlife, it is essential that we formally protect nationally important sites like the Swanscombe Peninsula for the wildlife that depends on them and for the survival of our natural world and future generations."

Matt Shardlow, chief executive of Buglife, said: “Biodiversity is in crisis, wildlife populations, particularly of insects, are in steep decline, many habitats and specialist species are increasingly rare and their fragmented populations are at risk of extinction.

"Too few wildlife-rich brownfield sites like Swanscombe Peninsula are protected, and this is the last chance to protect a large Thames Estuary brownfield site before it is too late.

"This is one of only two sites nationwide for the distinguished jumping spider. If the development is allowed on the Swanscombe Peninsula, this will push this special spider a step closer to national extinction.”

Emma Marsh. RSPB England Director, said: “The RSPB is increasingly concerned about the cumulative threat of unsustainable development on nature across England.

"In September, the Prime Minister announced the government’s “30 by 30” pledge – a commitment to protect 30% of UK land for biodiversity by 2030 – calling for immediate action and avoiding dither and delay.

"Saving nationally-important wildlife sites like Swanscombe is surely an easy win on the road to meeting that commitment.”

A grass-roots campaign group has seen its numbers swell with hundreds of members joining the newly formed Swanscombe Marsh Protection Campaign, which is working with the Kent Wildlife Trust and Buglife, Campaign to Protect Rural England (CPRE) and the Ramblers Association.

Founder Elizabeth Anderson said: "We are really glad to have ever growing support. We have 105 local people who have signed up to our campaign which launched one month ago.

'It is essential that we formally protect nationally important sites like the Swanscombe Peninsula...'

"The marshes provide a unique home for nature in an area of Kent which is being ever more corroded by development.

"The whole of the peninsula is falling within the development area. The environmental studies by the LHRC team left a lot to be desired.

"Various key checks had not been done. Air quality data was based on out of date information.

"The whole site is being considered for SSSI status, and none of it should be built on in my view.

"LRCH did not consider alternative sites, and have described it as a former industrial site with pylons - which completely neglects to realise that this is now a green space reclaimed by nature and much loved by locals.

"The site has been a source of escape through lockdown, and they wish to destroy this tranquil haven."

Ms Anderson said along with the rare jumping spider, a scarce lagoon worm found in very few places is also a protected species under the Marine Conservation Zone approval granted for the area in 2019.

She added: "The Tentacled Lagoon Worm lives in the estuary mud of the Thames, exactly where London Resort wants to put a pier and churn mud with ferries."

A spokesman for LHRC says inspectors have considered whether the documents provided in its 25,000-page application are appropriate for consideration and were accepted for examination last month.

The company says "any and all complaints or queries about the process of the application" should be raised with the Planning Inspectorate, which is now due to publish details on when views on the application can be submitted.

Ms Anderson added: "We will be submitting a full response covering a range of points, including on wildlife, the impact on local people and air quality.

"We will also look to ensure that all environmental legal obligations have been followed.

"We are also planning a local action campaign of leaflets and posters to show the strength of feeling in the local area, to coincide with the period of the Inquiry, and we will continue to work with local and national organisations to ensure that we can join together to fight this."

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