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The UK Bird Atlas

Lesser Scaup (Aythya affinis)Where and when to see it in the UK

Status not yet classified · reporting peaks February to March · Ducks, Swans, and Geese · BOU category A

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

Lesser Scaup (Aythya affinis)
Judy Gallagher, CC BY 2.0, via Wikimedia Commons
Peak months
Lesser Scaup: 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.

Lesser Scaup has been recorded in 129 of the 2,971 10 km squares covering UK land (4%) in records to 2026. Its strongest squares are in England, Scotland and Wales. Reporting peaks in February to March.

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
7% to 100%
Moderate
2% to 7%
Low
under 2%
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 62%<1%High
February 100%<1%Low
March 100%<1%Very high
April 51%<1%Moderate
May 9%<1%Low
June 16%<1%Moderate
July 17%<1%Very high
August 2%<1%Very high
September 5%<1%Low
October 15%<1%Low
November 59%<1%Moderate
December 44%<1%High

Squares with the highest reporting rate in February

SquareWhereShare of visitsClass
J37Belfast, Northern Ireland100%Very high
ND25Highland, Scotland100%Very high
NS61East Ayrshire, Scotland100%Very high
SO81Gloucestershire, England100%Very high
SS78Neath Port Talbot, Wales100%Very high
ST56North Somerset, England100%Very high
SW62Cornwall, England100%Very high
SZ09Bournemouth, Christchurch and Poole, England100%Very high
NS76North Lanarkshire, Scotland60%High
SX17Cornwall, England43%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.