Renewed hope for rare Roseate Terns

This year, the UK’s only Roseate Tern colony at Coquet Island, Northumberland, broke a record with 191 chicks hatched and 92% of those young birds successfully fledged. This is welcome news, particularly after this precious colony was heavily affected by avian flu in 2022 and 2023.

Roseate Terns are one of the UK’s rarest breeding birds. The species has long been admired for its elegance – a trait that it shares with its close relatives, like the Arctic and Common Tern, and has earned the family the nickname of ‘sea swallows’.  
 
Long streamers trail behind its short tail when in flight, while its glossy black cap and black bill contrast its dazzling white underparts. But the Roseate Tern’s most unique feature is its chest, which is a blush pink in the breeding season.  
 
In the 19th century, their beauty made ‘rosies’ a target for egg collectors and hunters. Their feathers were highly desirable during the fashion for feathered headwear. As these birds became scarcer, they became more sought after, and soon, they were extinct as a breeding species in the UK.

While Roseate Terns began to breed on Coquet Island again after protective legislation was introduced, the population of these birds has always been precarious. In the 1970s, there were just 16 pairs here. 

These terns are ground-nesting birds, often raising their brood in short vegetation or in rocky crevices. This means they’re especially vulnerable to predation and disturbance. They forage in shallow, sandy waters near their nests, where much of their diet is made up of declining sandeels. The nature of a seabird colony – thousands of individuals packed tightly together to nest – also means that disease can easily spread among breeding birds.  
 
Avian flu caused devastation on Coquet Island in 2022 and 2023. It is not known exactly how many Roseate Terns died from the flu, but surveys had revealed a 21% drop in the Coquet breeding since the outbreak. 

Coquet Island lies a mile off the Northumberland coast. Despite being just below 20 acres in size, it’s a seabird paradise and is home to around 45,000 breeding seabirds.  
 
The majority of the island is a flat, grassy plateau, and full of Puffin burrows! It is surrounded by low sandstone cliffs, and the shallow waters offer Roseate Terns and other seabirds prime feeding opportunities. 
 
The island supports breeding Puffins, as well as Common, Arctic and Sandwich Terns, Eiders, Razorbills, Fulmars, Kittiwakes, and Herring, Lesser Black-backed and Black-headed Gulls, and is protected under international and UK law. 

Coquet Island is managed specifically to increase the numbers of breeding seabirds. Nestboxes and tern terraces have been built for Roseate Terns, offering a place to nest with a lower risk of predation. There’s no public access to Coquet Island, which reduces the risk of disturbance to vulnerable species.  

The average number of chicks fledged per nest in 2024 was 1.39 from 126 breeding pairs. This number has only been beaten once before in the history of the colony when in 2017, 111 breeding pairs fledged 1.45 chicks (155 in total). This means that the island also saw its second most successful breeding season yet for Roseate Terns this year – but it is too early to say if this is a sign of recovery from avian flu.  

Despite the good news, the numbers of Roseate Terns returning to nest on the island this year were lower than in recent years and the hope now is that these numbers will increase next spring on the birds’ return from West Africa. 

For long lived species, such as terns, the recovery process could take many years and avian flu has not gone away - but the figures this year bring new hope for Coquet’s seabirds.  
 
Stephen Westerberg, RSPB Northumberland Coast Site Manager, explains: