A wildlife haven earmarked for the development of a multi-billion pound theme park has retained its special protected status.

The Swanscombe Peninsula has been confirmed as a Site of Special Scientific Interest (SSSI) for its grassland, wetlands, birds, and invertebrates – including one of the rarest spiders in the country.

Natural England, the government's nature adviser, initially granted protected status to the 260-hectare marshland site between Dartford and Gravesend in March due to its importance to rare wildlife.

Parts of the peninsula are currently earmarked for a new £2.5bn theme park, the London Resort.

Developers behind those proposals claim the scheme will bring jobs, money and regeneration of a brownfield site, while also providing much-needed investment into the environmental aspects of the site, leading to its protection rather than destruction.

They accused Natural England of trying to "frustrate" its plans and labelled its initial SSSI assessment as "unreasonable and unjustified".

But environmental campaigners have consistently argued the plans are at odds with the abundance of wildlife on site and lobbied the government's nature adviser to protect it.

The decision taken at a public board meeting today by Natural England to confirm the SSSI marks the last step in the designation process.

It heard how the site has been shaped by a number of industries including power generation, dredging, landfill and more than 150 years of chalk quarrying for cement production.

These processes have left an incredible assortment of grassland, scrub, wetlands, grazing marsh and saltmarsh habitat, providing ideal conditions for a unique variety of wildlife.

As such the area is home to more than 1,700 invertebrate species, which includes over a quarter of the UK’s water beetle species and more than 200 species that are considered of conservation importance.

It is also one of just two places in the UK where the critically endangered distinguished jumping spider is found, the other being West Thurrock Marshes in Essex.

The rich and varied habitats on the Peninsula also provide great conditions for breeding birds such as marsh harrier and bearded tit, and for nationally scarce plants threatened with extinction in Great Britain.

The meeting also took into account the benefits for humans with a large population living close by.

The England Coast Path, due to open in early 2022, will run around the northern boundary of the site, and with existing rights of ways provide people with important places to enjoy nature.

Tony Juniper, chair of Natural England, said: “The exceptional variety of birds, invertebrates, plants and geology on this site is an important reminder that nature often thrives in places that might seem scruffy and derelict at first glance.

"It also emphasises the need to ensure that nature is protected and restored in places where people live, so that they have easy access to the health, wellbeing and joy that nature can provide.

“In confirming the designation today Natural England again reiterated its commitment to continuing to work with developers and planners to ensure that nature can thrive alongside developments proposed for this area.”

James Seymour, Sussex and Kent area manager, Natural England, added: “The confirmation of Swanscombe Peninsula as an SSSI is great news for one of the richest known sites in England for invertebrates, providing a mosaic of habitats to support nature recovery across the wider landscape.

“This area is living proof that some of our most important species can thrive right on the doorstep of some of our most densely populated towns and cities, and this new SSSI will offer opportunities for people to connect with nature via the England Coast Path.

"Working in collaboration with our partners, special places like this will form the vital backbone of a national nature recovery network.”

Hilary Newport, director of CPRE Kent said they were "hugely relieved" by the decision and called for London Resort bosses to now scrap their plans.

'We believe London Resort should drop its plans to destroy this wonderful place.'

She said: “We are hugely relieved that the SSSI designation has been confirmed.

"The wildlife on Swanscombe Marshes is extraordinarily rich and varied, while the site provides an invaluable green lung for local people in an otherwise heavily over-developed part of the world.

"We believe London Resort should drop its plans to destroy this wonderful place.”

Local campaigner, Donna Zimmer, who is part of the Save Swanscombe Peninsula group, said: ”Natural England have completed a thorough and professional assessment which formally recognises Swanscombe Peninsula as one of the best wildlife sites in England.

"As a local campaign group, we are absolutely thrilled that our irreplaceable green space with such wonderful wildlife receives this much needed protection.

"We expect London Resort to recognise this and so withdraw their theme park proposal.”

The SSSI status does not mean the area is exempt from planning applications but it must fully be taken into account.

PY Gerbeau, the man behind the multi-billion pound plans, has vowed it will be built despite the "naysayers and doom-mongers".

But an examination of the theme park plans was delayed after London Resort asked for a a four-month extension to respond to the original SSSI decision in March.

Meanwhile business owners say the progress of the theme park and impact to their company is like "being on death row" amid uncertainty which could see hundreds of firms being "turfed out".

London Resort was contacted for comment.

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