Hertfordshire Natural History Society and the Herts Bird Club have formally objected to proposals for a 6,000 home village to be built on a site used by nesting Tree Sparrows and other rare and protected wildlife.

The 'Bowmans Cross' development included by Hertsmere Borough Council in its draft Local Plan threatens the last known colony of Tree Sparrows in Southeast England and more than a dozen other bird species on the adjacent Tyttenhanger gravel pits area that have been nationally 'Red-listed' due to conservation concerns. Other protected species recorded in and around the site include Brown Hare and Hedgehog, Common Toad, Great-crested Newt and the Small Heath and White-letter Hairstreak butterflies.

The HNHS does not normally comment on planning proposals, viewing its role as one of collecting, verifying and collating local wildlife records. It has taken the unusual step of objecting to the 'Bowmans Cross' proposals in recognition of more than 20 years hard work led by the Bird Club to conserve the last Hertfordshire Tree Sparrow colony, including nest boxes, supplementary feeding, ringing and tagging.

The Society welcomes recent practical steps taken with the would-be developer Urban & Civic in hope of extending and shifting the Tree Sparrow's breeding site towards land around the Tyttenhanger gravel pits. However, it insists that it is only a step towards the kind of comprehensive biodiversity mitigation strategy needed to match the proposed scale of development.

The response proposes that the scale of development to be reduced and limited to land south of Coursers Road. It also calls for a large, new nature reserve to be created and maintained in perpetuity north of the road, centred on the Tytenhanger lakes.

It adds that: "Unless a substantial area is created for wildlife to the north of the  road (acting as a ‘cordon sanitaire’ for humans and predatory pets) we anticipate that the proposed settlement will fall far short of national planning policy requirements by failing to mitigate, let alone enhance local biodiversity."

The HNHS response includes a letter of concern sent to Hertmere Council two years ago when the 'garden village' proposal was first mooted. It also incluoded a list prepared by the Herts Environmental Record Centre (HERC) of more than 250 species recorded in and around the site that have been internationally and nationally listed or legally protected because of conservation concerns. They include Herts-rare invertebrates, mosses and plants.