For the first time in more than 30 years hundreds of threatened sandwich terns have settled to nest at a Suffolk nature reserve - providing a spectacular sight and sound for visitors.

For the first time in more than 30 years hundreds of threatened sandwich terns have settled to nest at a Suffolk nature reserve - providing a spectacular sight and sound for visitors.

The terns were once a familiar sight at RSPB Minsmere, regularly breeding there until 1978, but since then only a handful of pairs have nested at the reserve.

Now, to the delight of bird enthusiasts, the terns have suddenly returned, joining record numbers of gulls at the site.

During the last fortnight more than 1000 terns have arrived en-masse on the Scrape and nearly 400 pairs have started to nest on the shingle islands.

It is not known why the terns have suddenly come back to Minsmere, but as they arrived late, experts say it suggests that they may have moved from a site elsewhere, possibly in North Norfolk, following some unknown disturbance.

But Adam Rowlands, senior site manager at Minsmere, said their return was no coincidence. 'Sandwich terns are known for nesting among large colonies of black-headed gulls, where they benefit from the extra protection offered by the gulls against larger predators, especially big gulls,' he said. 'It is no coincidence that the terns have returned to Minsmere, with record numbers of black-headed gulls on the Scrape.'

He added: 'Minsmere's Scrape is a true seabird spectacle this year, with 1100 pairs of gulls, nearly 400 pairs of sandwich terns and 190 pairs of common terns - the most since 1974. If you're lucky you might even spot a rare roseate tern or Mediterranean gull among them.'

The RSPB said that unlike their larger cousins, it looks like being a poor year for the scarce little tern, with only two or three pairs nesting on the beach at Minsmere.

After a good season last year, it appears that the tiny seabirds have relocated further north, with some nesting on the shingle beach between Dunwich and Walberswick, and good numbers settling within the main colony on Yarmouth's North Denes.

Like most terns, sandwich terns nest in large colonies. Their chosen nest sites, usually on coastal lagoons, islands or beaches, are easily disturbed, leaving colonies vulnerable.

There are about 12,500 pairs at various colonies around the coast. Up to 750 pairs nested at Minsmere form 1965 to 1978, but apart form 23 pairs in 1995 there have only been occasional nesting attempts since then.