From the Arctic tern to the Atlantic puffin, find out which seabirds are facing a high risk of decline following recent study
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A recent study into the population of seabirds across the UK has found an overall decrease in the populations of many species – with 18 out of a total 26 species assessed found to be threatened with extinction from Great Britain.
The updated status assessment – published by British Birds – was carried out in two stages. The assessment initially took place before the outbreak of the highly-infectious H5N1 strain of Highly Pathogenic Avian Influenza (HPAI), which began in 2021. To ensure this outbreak was taken into account, a further secondary analysis of particular seabird species was rolled out to see the impact of HPAI.
Below are the species from the study which either stayed or moved to the Red List of the UK’s Birds of Conservation Concern (BoCC).
Leach’s storm-petrel (Hydrobates leucorhous)
The starling-sized Leach’s storm-petrel (Hydrobates leucorhous) was added to the Red List due to concerns over its population decline before the outbreak of HPAI. It has experienced a breeding population decline, as well as a localised breeding concern – meaning more than 50 per cent of the UK population is found at ten or fewer sites.
Leach’s storm-petrels breed on remote islands off the UK, and feed even further afield. Spending most of their time at sea, most birds then migrate to the tropics in the winter. The species face threats from mammals inadvertently introduced to the islands they inhabit, such as cats and rats.
The seabird is also considered of international importance due to findings that the UK holds at least 20 per cent of the European breeding population.
Great black-backed gull (Larus marinus)
Much like the Leach’s storm-petrel, the great black-backed gull (Larus marinus) has been added to the BoCC Red List owing to pre-HPAI population declines. Breeding across the North Atlantic and adjacent seas, the species was historically found predominately in Britain and Ireland.
The species has also faced a severe decline of more than 50 per cent of its breeding population in the UK in the long term, and a decline of between 25–50 per cent of its non-breeding population
Between 1985 and 2021, it is estimated that the global population of the species plummeted by 43–48 per cent. Although the reasons for their decline are unclear, research suggests that an overall decline in food availability in their natural habitat, as well as reduced discards from the fishing industry, may be to blame.
Common gull (Larus canus)
The common gull (Larus canus), despite its name, is more scarce than the black-headed gull or herring gull. It is uncommon to find the species in many inland areas, with its preference to breed at the coast. Recently, the seabird has been more regularly spotted around housing estates, landfill sites and towns in winter.
Over the last 25 years, the common gull has also experienced a severe decline of more than 50 per cent its in breeding population. A decline in its numbers can be attributed to pre-HPAI factors, such as predation and changes in land which cause degradation and loss of habitats.
Arctic tern (Sterna paradisaea)
The Arctic tern (Sterna paradisaea) – with its distinct long tail streamers and black cap – is a coastal bird and makes yearly migrations between the United Kingdom and the Antarctic. Their population – as well as breeding range – have faced a severe decline of more than 50 per cent over a period longer than 25 years. It, too, is one of the five birds to be added to the BoCC Red List following the recent assessments.
In the 19th century, the Arctic tern – as well as the common tern – were targeted in the feather trade, but now the species faces threats from fish shortages, degradation of beaches and island nesting habitats, as well as human disturbances at colonies.
Great skua (Stercorarius skua)
Due to severe impacts from HPAI – resulting in at least 2500 reported deaths of skua individuals in Scotland in 2022 alone – the Great Skua (Stercorarius skua) has joined the Red List. More than 50 per cent of the UK population is found at ten or fewer sites –and the UK accounts for at least 20 per cent of the European breeding population – and the species migrate to the northernmost isles of the UK from Spain and Africa.
Kittiwake (Rissa tridactyla)
The kittiwake (Rissa tridactyla) – one of the most sea-loving gulls – was already placed on the BoCC Red List in the previous assessment, but has not changed its status since. The seabird is marked as globally threatened according to the IUCN Red List, and it is facing a severe decline of more than 50 per cent of its UK breeding population over a period greater than 25 years.
A major factor affecting their population is changes to sand eel populations, which may be affected by fisheries and changes to sea surfaces temperatures due to climate change. Appropriate management of fisheries may help to restore the kittiwake to its former numbers.
Roseate tern (Sterna dougallii)
The roseate tern (Sterna dougallii) – which gets its name the pinkish tinge adults get to their underparts during summer – has stayed on the BoCC Red List, and is classed as a rare breeder species due to its UK breeding population falling to less than 300 pairs. The seabird has also suffered a severe decline in its breeding range, with factors such as vegetational changes on breeding areas and competition with gulls causing their decline.
Conservation efforts to protect the species have focused on their wintering grounds in northwestern Africa, as well as management of their breeding sites.
Herring gull (Larus argentatus)
The herring gull (Larus argentatus) has faced a series of threats, from oil pollution to pesticide contamination, meaning its status on the BoCC Red List has not changed since the last assessment. The seabird has an extended breeding range – southward along the Atlantic Coast – but it is being displaced by the great black-backed gull in northern areas of its range.
The population has also experienced a non-breeding population decline of more than 50 per cent over the last 25 years.
Atlantic puffin (Fratercula arctica)
With more than 50 per cent of the UK population found at ten or fewer sites, the Atlantic puffin (Fratercula arctica) has remained on the BoCC Red List, and is also on the IUCN’s Red List.
In the summer, it breeds in burrows on islands in the North Atlantic, before wintering at sea – although warming ocean temperatures are contributing to breeding failures across the population. Half of North America’s Atlantic Puffins breed in one particular area: Witless Bay in Newfoundland, Canada.
