This tern has a white body, black cap and black bill with a yellow tip. Birds breeding in Britain and Ireland move to the West African coast for winter.
It is mostly white, with a black cap. Its bill is black with a yellow tip, its short legs are black, and in flight it shows grey wedges at the wing tips and a forked tail.
Sandwich Terns breed mainly on coastal islands in Sweden. Surveys from 2007 to 2023 confirmed 53 breeding sites. Many colonies were within or near Black-headed Gull colonies, and nesting locations sometimes shifted between years. Researchers counted nests with eggs or chicks to estimate breeding pairs.
National counts ranged from about 390 to 570 pairs in 2007–2014, then rose from about 630 in 2015 to about 1,830 in 2021. About 1,540 pairs bred in Sweden in 2023. Across all years, four large colonies held roughly 55% of the cumulative breeding pairs recorded from 2007 to 2023. Regional counts show both movement among sites and longer-term changes.
An extinction-risk assessment has not been added yet.
About 55% of the cumulative breeding pairs recorded during the study period were concentrated in four large colonies. Annual counts across regions, together with records of shifting island sites, can guide conservation toward both major colonies and newly used locations.