The conservation charity has suggested 71 sites which are important for breeding seabirds and require protection, including Coquet Island, the Northumberland Shore and The Farne Islands.

The RSPB said under current law, the land where seabird colonies nest are protected but their offshore feeding areas are not and, as a result, their breeding levels can be threatened.

The extent of marine sites around the UK which are fully protected is one square mile in every 100,000.

The RSPB described the existing level of protection as "like a tea bag floating on the surface of an Olympic-sized swimming pool".

The charity said birds such as the black guilliemot, the gannet and the roseate tern could benefit from marine-protected areas which could tackle problems such as overfishing, offshore industry and pollution.

There is no mechanism for protecting the areas suggested in the Safeguarding our Seabirds: Marine Protected Areas for the UK's Seabirds report, the RSPB said.

They could be established under the Marine Bill, a draft of which is due to be published soon by the Government.

Kate Tanner, marine policy officer for the RSPB, said: "We have plundered the riches of the UK's seas for centuries at great cost to wildlife.

"The sea has shaped our islands' history, geography and culture and now, as time runs out for marine wildlife, it is crucial that we act decisively to protect the environment that defines us.

"From basking sharks to barnacles, cod to cold-water corals, the UK's seas contain an immense variety of threatened and beautiful wildlife.

"Our seas also support huge populations of seabirds, with some species occurring around the UK in larger numbers than anywhere else in the world."

She said marine wildlife deserves far better than the current level of protection.

A Defra spokesman said: "Over 1.8 million hectares of UK waters that hold important marine species and habitats are already protected and we welcome the RSPB's work to highlight the importance of protecting sea birds.

"As Ministers have said we are committed to protecting marine species, habitats and birds, and the forthcoming Marine Bill will provide a variety of measures including a network of protected areas."
Last autumn the Government faced criticism from conservation groups for its failure to include a full Marine Bill in its programme for the current session of Parliament – including only a draft bill.