A nature reserve is hoping to attract greater numbers of two of Britain's rarest bird species after landing a £150,000 grant.

The RSPB's Otmoor Reserve in Beckley, near Oxford, is aiming to increase the number of bitterns and snipe that come to the wetland, after securing funding from Viridor Credits.

The money is to be spent installing sluices in the wetland habitat to ensure water stays at the correct level needed by different birds.

Work restoring the site, which was mainly arable farmland 10 years ago, has seen a single bittern recorded at Otmoor in four of the last five years.

But managers of the reserve want to get a breeding pair there to boost numbers of the protected species.

Five pairs of snipe came to the wetland to breed last year, but attracting more pairs is seen as particularly important because Otmoor is the only known site in central England where the bird has been spotted.

Richard Miller, the reserve's estate warden, said: "Although we have only had a single bittern recorded in four out of the last five years, that's exciting because there were only 51 males recorded in the whole of the UK last year.

"They are a solitary territorial bird, but an area has been set out for two bitterns now so we are hoping to get a breeding pair at Otmoor. It is a bird that has had a massive decline, but the RSPB's national project is seeing it start to make a comeback again."

"We are pleased to see the snipe return here too, but increasing their numbers is the challenge now. We hope the new equipment will help the population start to increase and then the birds could start to spread out in other areas of Oxfordshire."

Other notable species of bird coming to the site include hobbies, little egrets, skylarks, tufted ducks and wigeon.