Ever heard of the Sussex Diving Beetle?  It was common in ditches on the Lewes Levels in the 1970s but steadily declined and was last seen in 2002.  Experts fear that the source of water for the ditches is polluted by the runoff from the A27.

How about the Brighton Wainscot Moth?  The last three were seen on Salisbury Plain eight years ago.

These are two sad local examples of a national and international phenomenon: animal species which have been lost altogether.

The latest Government assessment shows that six of the species on its ‘Biodiversity Action Plan' list have been lost from the UK since the Plan was published in 1994.

Wildlife habitats are also in trouble with over half of habitats deteriorating compared with just a fifth improving.  386 of the Government's sub-targets for biodiversity - that's nine out of ten - have been missed.

These losses, caused by climate change, pollution and development, really matter.  Biodiversity - which means the variation of life in the natural world around us - supports the ecosystems which give us clean water, clean air, natural flood alleviation and pollination.

As Sussex beekeepers have told me, the serious current decline in British bees is extremely worrying as they play a vital role in making crops grow - insects pollinate a third of everything humans eat.

So this Friday, I'm visiting a nature reserve in Oxfordshire with David Cameron, where we'll be announcing an exciting new plan for "conservation credits", to enable new investment in wildlife and habitat projects where development causes biodiversity loss.

And on Saturday I'll be visiting an exhibition in Arundel of photographs and drawings in aid of the Butterfly Conservation Sussex Branch.   Butterflies have just had their second worst year since records began.

With greater determination we can arrest these declines in our species and habitats - but we need new incentives to enhance nature conservation, rather than failed government ‘Action Plans' where targets keep being missed.

Michelle Taylor