The colourful insects are being forced out of their natural habitats by growing human populations.

The British Dragonfly Society (BDS) has said 36 per cent of the 39 British dragonfly species are in decline, and three species – Dainty damselfly, Norfolk damselfly and Orange spotted emerald – have disappeared altogether, thanks to a loss of natural habitats.

Northamptonshire had 25 species spotted last year according to the local branch of the British Dragonfly Society and they are usually spotted from the end of April.

Henry Stannier, ecology groups officer for Northamptonshire Wildlife Trust, said dragonflies spent the majority of their lives under water and it was there that they were most under threat.

He said: "They are very dependent on water, that's where they spent most of their lives.

There are improvements being made to rivers but there are still some problems.

Dragonflies used to benefit from winding rivers and shallow areas, but we have gone through a period where everything has been cleaned up and sanitised, and now we are going back again."

Popular breeding sites for Northamptonshire dragonflies are around the River Nene and Ouse, and in the many gravelpit sites like Storton's Pits in Sixfields and Stanwick Lakes, near Rushden. Under the water, dragonflies breathe through gills and hunt the larvae of smaller insects like midges and mosquitoes.

But once they have left the water they breathe air through their mouths and eat the fully formed versions of midges and mosquitoes.

Mr Stannier said: "Most people don't realise how important water is to dragonflies as when they see them they are not in that environment."

He said anyone who wanted to help dragonflies would do well to install a pond in their back garden, but more importantly, to be wary of wasting water.

He said: "The more sustainable the use of water, the more there will be left for wildlife, don't waste so much."