A £2,000 reward has been offered to help catch thieves who stole rare bird’s eggs.
The RSPB and Teesmouth Bird Club are offering the reward for information leading to a conviction after the incident at Crimdon.
In the early hours of June 19, more than 50 little tern eggs were stolen from Crimdon beach, where 65 pairs of the birds had been nesting.
The crime was discovered by horrified local volunteers from the Little Tern Project, funded by Teesside’s Industry Nature Conservation Association to protect the site.
Little terns are one of the UK’s most threatened seabirds.
The theft of the eggs could have had a catastrophic effect on the survival of species in the North-East, say the experts.
Following the theft, some of the birds flew to another breeding ground on the Humber.
Fortunately, enough remained to lay eggs and ensure the future of the nest site.
Little terns nest on sand and shingle, often using public beaches, which means they are susceptible to human disturbance.
But it also means they are vulnerable to attack from natural predators like kestrels, sparrowhawks and foxes.
In recent years, the number of little tern nest sites has declined, making the species a cause of concern for conservationists.
Stealing wild bird eggs is illegal and carries a maximum six-month custodial sentence and or a £5,000 fine.
The little tern theft is a particularly serious crime because of the vulnerability of the species and the large numbers of eggs that were stolen, say officials.
Alistair McLee, of Teesmouth Bird Club said: “The club members were outraged to discover this financially motivated theft.
“This attractive, and locally rare species, has enough problems to contend with whilst breeding, without this criminal action.
“The dark ages of egg theft are still with us, threatening our local wildlife heritage.”
Mark Thomas, senior investigations officer for the RSPB, said: “Little terns are placed within the top five birds for which egg collecting has a serious impact.
“A robbery of this scale is highly significant at both regional and national level.”
Anyone with information should contact Durham Police on 101 and quote incident number DHM19/06/2013-0202.
Alternatively, people can call the independent charity Crimestoppers anonymously on 0800 555111.