Conservationists in Oxfordshire say the drought has already had a noticeable effect on the county’s wildlife.

It comes as the Environment Agency warns that some ponds and streams could dry up completely in the looming drought.

Thames Water announced last week that a hosepipe ban will be imposed from April 5 following one of the driest two-year periods in southern and eastern England since records began.

Since March 2010 the region has had 35cm less rain than normal.

Robin Buxton of Oxfordshire Nature Conservation Forum, said: “It is still March and there is still dew and frost so on land there isn’t that appearance of drought.

“At the moment the really critical thing is water bodies so I’m concerned about species that live in or around them.

“I’m concerned about species such as toads, frogs and newts. Even dragonflies because their larvae all live in the water.”

Alan Hart, warden of Boundary Brook Nature Park, said: “Normally we have a lot of frogs spawning but this year we haven’t had one. We’ve got two large ponds and one smaller one and there’s nothing in any of them.”

In its latest briefing, the Environment Agency said that after the previous week’s “welcome” rain, the past week had been the driest in England and Wales for around six months.

No more than a few millimetres of rain fell across the country, with the South East region receiving the most rain in the week – just 4mm.

Debbie Lewis, of Berkshire, Buckinghamshire and Oxfordshire Wildlife Trust, said: “There is very little that we can do because obviously we can’t make it rain.”

But Alexis Pym of the Earth Trust felt the county’s wildlife would be able to adapt to the dry weather.

She said: “The only impact I have seen is lower levels in ponds but wildlife is quite adaptable and while there are still rivers and streams it will find a way to survive.”

On Monday, the Environment Agency warned that, in drought-affected areas, it was likely some streams, ponds and shallow lakes would dry up.

Alistair Driver, Environment Agency national conservation manager, said: “The amount of water we use at home and in our businesses has a direct effect on the amount of water available in our rivers and for wildlife.

“We would urge all water users to use it wisely to help protect our valuable natural environment.”