And they fear the reason is that the number of people allowing their dogs to get too close to the birds has increased.
The Tees Valley Wildlife Trust’s little tern warden, Derek Wood, said he worried any additional stress at the site would lead to the birds abandoning their nests and not returning to the area.
There are currently 55 nesting pairs on the beach at Seaton Carew while volunteers expected there to be up to 110 pairs.
Derek said: “The total dog count in the exclusion zone for May was 427 and that is only from monitoring between 2pm to 8pm, Monday to Friday. The exclusion zone is clearly not working, especially if you consider the 93 violations in one day in June.”
Derek added that, after years of improvement after establishing a safe area around the terns, he had “no idea” why it had changed.
When the first little terns were arriving this year, the protective fencing around their normal nesting ground was washed away in high tides.
The protective barrier has since been repaired and the outer dog exclusion zone has been put in place on the surrounding area of the beach to try to prevent any distress for the terns.
“The birds are arriving already spooked by flooding and disturbance so any additional threat will probably move them on to another site,” he added.
People can report issues – including any breaches of the dog exclusion zone – at online.hartlepool.gov.uk, using the section ‘Report an Issue in the Area’.
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