BULLDOZERS converting Calne's former allotment site into a housing estate have slithered to a halt after a colony of slowworms were discovered on site.

Petitions, public meetings and numerous letters failed to stop the town council selling the six-acre allotment site to Hills Property Ltd in March for just over £1.3 million.

But heavy machinery ground to a standstill within 20 minutes of work starting, after developers discovered a colony of residents who were not turfed out when the allotment holders were evicted a year ago.

Slowworms are shy reptiles, which can grow up to 50cms in length. They are snakelike in appearance but are in fact legless lizards. The creatures are protected under the Wildlife and Countryside Act of 1981, but their habitats are not.

The diggers have now been withdrawn from the site and work delayed indefinitely to allow environmental consultants to conduct a survey of the slowworms and decide how best to deal with them.

Hills Property Ltd's commercial director, Nick King, said: "When these creatures were discovered, our company production director immediately got in touch with English Nature and the Wiltshire Wildlife Trust.

"The next day our heavy machinery was removed from the site and we have been working very closely with those parties concerned to resolve the situation."

The developers plan to build more than a hundred houses on the site and 17 flats for social housing. The plan also set aside land in the western corner of the site for 26 allotments.

The developer's environmental consultant, Colin Menendez, said the delay could last all summer or even until next year.

Slowworms eat slugs, spiders and beetles and live in rough grassland environments. They can be seen from March to October, but in winter they hibernate underground.

Mr Menendez said the most likely solution is that the slowworms will be gathered up and then relocated to a new home nearby, but he added little can be done at the moment because it is their breeding season.

Plastic sheet fencing is now being installed around the perimeter of the site to form an exclusion zone, which will prevent slowworms on the site escaping.

Corrugated pieces of metal are also being placed around the site to help the consultants conduct their survey.

The slowworms hide under the sheets and enable the consultants to estimate numbers and gather the reptiles for relocation.

English Nature Conservation Officer for North Wilts, Katie Lloyd, said English Nature was surprised to hear about the slowworms because it has no record of their presence at the site.

English Nature is now waiting for the consultants' report, which it will either approve or amend.

Local residents' groups opposed to development of the land have started a campaign to raise awareness about the slowworms.

Calne Town Councillor Ellie Bland, said: "We are concerned about what's going to happen to them, but we have been reassured by English Nature that they will be taken to a place of safety."