Beacon Lagoons is run by the Spurn Bird Observatory Trust with support from the RSPB, Yorkshire Wildlife Trust, Natural England, the Environment Agency, Humber Nature Partnership and South Holderness Countryside Society.
During the breeding season, three wardens and a team of volunteers protect the colony with 24-hour watches.
They also clear away some of the vegetation so the terns have access to the sand to build their nests.
Lead warden Tate Lloyd, who has travelled from south Wales for the past three years, said watching the birds return each year and raise their chicks was “something very special”.
He added: “The local community here has helped us to protect these precious birds, too, helping to ensure the little terns have been given the space they need to nest and breed.
“Everyone is proud of what’s been achieved.”
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