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The UK Bird Atlas

Caspian Tern (Hydroprogne caspia)Where and when to see it in the UK

Summer visitor · reporting peaks July · Skimmers, Noddies, Terns, and Gulls · BOU category A

Records to 2026-08-16 · build 2026-08-31

Caspian Tern (Hydroprogne caspia)
Mdf, CC BY-SA 3.0, via Wikimedia Commons
Peak months
Caspian Tern: relative reporting rate by 10 km square, September

Contains OS data © Crown copyright and database right 2026 (grid squares, place names from OS Open Names). Northern Ireland place names: OSNI Open Data, OGL v3.0. County and country boundaries: Office for National Statistics, Open Government Licence v3.0. Coastline: Natural Earth. Bird records from the data partners listed here.

Caspian Tern has been recorded in 74 of the 2,971 10 km squares covering UK land (2%) in records to 2026. Summer visitor in the UK. Its strongest squares are in England, Wales and Scotland. Reporting peaks in July.

Conservation status: Least Concern (IUCN Red List, LC)
View on the IUCN Red List
Relative to this species' best squares (how classes are calculated)
Very high
100% or more of visits
High
5% to 100%
Moderate
1% to 5%
Low
under 1%
Surveyed, not recorded
at least 20 qualifying visits, no record
Insufficient records
too few visits to say
Lighter fill
Few visits, lower confidence
Small dot
Occasional: a single record, or out of season

Seasonality

Reporting rate by month, relative to the peak month
MonthRelative to peakShare of visitsTypical class
January 0%<1%Insufficient records
February 0%<1%Insufficient records
March 0%<1%Insufficient records
April 0%<1%Very high
May 33%<1%Very high
June 74%<1%Very high
July 100%<1%Moderate
August 31%<1%Low
September 1%<1%Low
October 0%<1%Low
November 0%<1%Insufficient records
December 0%<1%Insufficient records

Squares with the highest reporting rate in July

SquareWhereShare of visitsClass
SE36North Yorkshire, England100%Very high
SE82East Riding of Yorkshire, England100%Very high
SJ67Cheshire West and Chester, England100%Very high
SP68Leicestershire, England100%Very high
SS59Swansea, Wales100%Very high
SS78Neath Port Talbot, Wales100%Very high
TL91Essex, England100%Very high
TR01Kent, England100%Very high
SO71Gloucestershire, England32%High
TA12North Lincolnshire, England18%High

Spotted an error in a square? Report it and it goes into the review queue. Read the methodology for how classes, flags and sensitive-species rules work. Data to 2026.