A very English ark: New homes for wildlife

In the UK's biggest exodus of creatures, thousands are being relocated from the Thames estuary to make room for a container port.

In what is described by many as the largest wildlife relocation programme in the world, tens of thousands of animals are being removed from a major development in the Thames estuary to new homes in nature reserves throughout the UK.

Tomorrow, 100 water voles will be driven in ventilated lorries to the River Colne in Essex, where they will be joined over the next month by at least 200 more of the endangered species from the Thames site.

About 50,000 animals have already been captured from the 1,500-acre site, 25 miles east of central London on the north bank of the Thames. There are at least 100,000 more animals left to move before the site's owners, DP World, can construct London Gateway – the UK's first 21st-century deep-sea container port.

To date, more than 350 endangered great crested newts and approximately 30,000 smooth newts have been moved from the site and placed in 23 newt ponds about 500 yards from the Gateway site. Four species of reptile, including thousands of grass snakes, adders, slow worms and lizards, have also been removed to locations spanning from Wiltshire to West Mersea, Essex. Fifty-two species of birds are on the site and 7,000 of them will have to be provided with new habitats by DP World. Those involved in the scheme hope the wildlife will relocate naturally, but this remains to be seen.

It took almost eight months and more than 500 traps to capture the hundreds of water voles on the DP Gateway site. They were caught as they stepped into the tunnelled boxes looking for food and bedding. They were then held in the traps until released by an ecologist on the site.

In partnership with the Essex Wildlife Trust and two contracted ecology consultants, DP World will start the water vole relocation project tomorrow, when it places 100 of them in soft pens along a four-mile stretch of the River Colne. According to water vole ecologist Rebecca Northey, who is working on the project, the animals will be placed in release pens and fed for five days, after which they are free to burrow out into the surrounding water. Twenty voles will receive "radio collars" so that ecologists can track their movements for the first three months. DP World has received a licence from Natural England, the Government's adviser on the natural environment, which allows relocation to take place.

According to Darren Tansley, the Water for Wildlife officer for Essex Wildlife Trust which is helping to co-ordinate the release, more than 90 per cent of all water voles in the UK have been lost in the past 30 years – a big problem considering they provide food for a number of animals higher up the food chain. He blames the North American mink for their near-extinction, claiming they can wipe out whole populations of water voles after a year of being present along rivers.

After admitting that he would have preferred a "natural recolonisation" process to have taken place instead of a human-led relocation, Mr Tansley stressed that DP World had agreed to fund the continued removal of mink in Essex for the next five years. "There is always some risk in any movement of animals between habitats, but I am hoping that they will adapt well to their new environment, breed and recolonise the whole river," he told The Independent on Sunday.

DP World's animal relocation project comes under its £50m environmental programme, which is looked after by 17 different consultants. Marcus Pearson, the environmental manager for the £1.5bn London Gateway project, said he thought that DP World's "relocation project was one of the biggest in Europe, or indeed, the world".

DP is not yet able to say when the deep shipping channel would be open. The Independent on Sunday has also not seen a detailed list of the animals so far relocated, despite several requests, receiving only an estimated breakdown by Mr Pearson.

While DP World is bound by law to create alternative habitats for the wildlife that it removes from the London Gateway site, it is not required to do the same for marine life. Mr Pearson said there are more than 80 species of fish in the Thames estuary, including the juvenile Dover sole, which is found here in higher concentrations than anywhere else in the North Sea.

Mr Pearson said: "Europe's most expensive marine monitoring programme ever" is being undertaken to keep a constant track of the levels of contaminants in the sediment that is dredged up during the port's construction. He said that if it ever rises above suggested levels, it can be automatically modified, adding that the fish should naturally leave the area during this process, returning three or four years later once it is complete.

However, local fisherman Paul Gilson from Leigh-on Sea said that this was known in the industry as the "Disney effect" and thought highly improbable by those in the industry. He said: "Fish just don't have this ability to understand when they are in danger, and if their environment changes, we don't know if they will come back."

The chairman of Kent and Essex Sea Fisheries Committee, John Lamb, said he had concerns about the information that was being received. "Their scientists say the nursery beds will re-establish themselves after the main dredge, but we need to make sure this does happen," he said. "I think that DP World should try to re-establish habitats for the marine species as they have with the water voles and birds. There are concerns that they could be affected for many years."

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Water Voles are being released into the River Colne this week. By July 300 will have been relocated

350

Great Crested Newts (Endangered) have been removed so far into 23 ponds north of the site, along with 30,000 smooth newts

2,000

Grass Snakes and Adders have been relocated to sites in Wiltshire and West Mersea

52

Species of Birds about 7,000 birds in total on the site are not being artificially captured but will have to relocate. These include the cettis warbler, reed bunting, corn bunting and skylarks

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Species of Fish will also be affected, as the estuary provides important nursery and feeding grounds for many, including herring, whiting, plaice, sprat, Atlantic cod, and sand eels

6,000

Lizards have been relocated to sites in Wilshire and West Mersea