Pomarine Skua

Stercorarius pomarinus

Introduction

Pomarine Skuas breed across the northern tundra regions of Russia, Alaska and Canada. The species is a passage visitor to Britain & Ireland, with more records during autumn passage (August to November) than spring (May).

Autumn passage sees birds passing down both sides of Britain & Ireland, with adult passage typically peaking earlier than that of juvenile birds. Spring passage tends to see most birds reported from off the south coast of Ireland and north-west Scotland.

Key Stats

Scarce

745g

2-2

<1%

BTO Records

28k records

Population and distribution stats for:

No data

No current data

No current data

No data

No current data

838.5% expansion

Identification

Curated resources to aid in the identification of Pomarine Skua

ID Videos

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This section features BTO training videos headlining this species, or featuring it as a potential confusion species.

Skuas

Status and Trends

Population size, trends and patterns of distribution based on BTO and partnership surveys and atlasses with data collected by BTO volunteers.

Conservation Status

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This species can be found on the following statutory and conservation listings and schedules.

UK Birds of Conservation Concern

Green listed

Species of European Conservation Concern

Least Concern

IUCN Red List of Threatened Species (global)

Least Concern

Schedule 1 Licence required (to disturb)*

Birds Directive Annex 1

Listed on the Annexes of*

Bern(III)

* A guide only. Check details with the original legislation, especially those marked with an asterisk. See About Birdfacts for more information.

Population Size

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BOU Category

Source

First Record*

East Sussex, 1818

* First documented occurrence. Most species undoubtedly occurred before this. See About Birdfacts for more information.

Population Change

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Population trends of this scarce species are not routinely monitored.

Distribution

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Pomarine Skuas mostly winter in the tropics and the records shown on the winter distribution map here mostly involve passage birds in November.

Occupied 10-km squares in UK

These figures come from Bird Atlas 2007 and indicate how widespread a species is.

No. occupied in winter

192

% occupied in winter

6.4%

Bird Atlas distribution maps show where bird species breed or winter in Britain and Ireland. For breeding maps, larger dots indicate higher certainty the species bred in that area.

Click the map to enlarge,
or view it on Bird Atlas Mapstore.

Click the map to enlarge,
or view it on Bird Atlas Mapstore.

To view and download up-to-date distribution information aggregated from across BTO and partnership surveys and schemes, see our data holdings on the NBN Atlas.

European Distribution Map

European Breeding Bird Atlas 2

Distribution Change

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Change in occupied 10-km squares in the UK

These figures come from Bird Atlas 2007-11 and indicate by how much occupied areas have expanded or contracted over recent decades.

% change in range in winter (1981–84 to 2007–11)

838.5 %

Bird Atlas distribution change maps show how bird distributions have changed through time. Coloured upward-pointing triangles show places apparently colonised over the period; grey downward-pointing triangles show places apparently vacated. Shading show places occupied.

Winter Distribution change for Pomarine Skua

Click the map to enlarge,
or view it on Bird Atlas Mapstore.

Seasonality

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Spring passage of Pomarine Skuas is in April and May, followed by a long autumn passage season that can extend into late autumn and some birds may winter.

Weekly pattern of occurrence

The graph shows when the species is present in the UK, with taller bars indicating a higher likelihood of encountering the species in appropriate regions and habitats.

Phenology graph — Weekly occurrence patterns (shaded cells and reporting rates (vertical bars) based on BirdTrack data. Reporting rates give the likelihood of encountering the species each week.

Movement

Information about Pomarine Skua movements and migration based on online bird portals (e.g. BirdTrack), Ringing schemes and tracking studies.

Britain & Ireland movement

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View a summary of recoveries in the Online Ringing Report

European movements

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EuroBirdPortal uses birdwatcher's records, such as those logged in BirdTrack to map the flows of birds as they arrive and depart Europe. See maps for this species here.

Biology

Lifecycle and body size information for Pomarine Skua, including statistics on nesting, eggs and lifespan based on BTO ringing and nest recording data.

Productivity and Nesting

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Nesting timing

Typical (exceptional) number of broods

Source

Egg measurements

Typical length x width

64x44 mm

Mass (% shell)

66g (6%)

Source

Clutch Size

Typical number

2-2 eggs

Observed minimum and maximum

1-3 eggs

Source

Incubation

Incubation by

Male + Female

Typical duration

27-25 days

Source

Fledging

Type of chick

Altricial, downy

Typical duration

32-31 days

Source

Survival and Longevity

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Survival is shown as the proportion of birds surviving from one year to the next and is derived from bird ringing data. It can also be used to estimate how long birds typically live.

Classification, names and codes

Taxonomy, names and species codes for Pomarine Skua

Classification and Codes

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Order: Charadriiformes
Family: Stercorariidae
Scientific name: Stercorarius pomarinus
Authority: Temminck, 1815

BTO 2-letter code: PK
BTO 5-letter code: POMSK
Euring code number: 5660

Alternate species names

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Catalan: paràsit cuaample
Czech: chaluha pomoranská
Danish: Mellemkjove
Dutch: Middelste Jager
Estonian: laisaba-änn
Finnish: leveäpyrstökihu
French: Labbe pomarin
Gaelic: Fàsgadair-donn

German: Spatelraubmöwe
Hungarian: szélesfarkú halfarkas
Icelandic: Ískjói
Irish: Meirleach Pomairíneach
Italian: Stercorario mezzano
Latvian: videja klijkaija
Lithuanian: bukauodegis plešikas
Norwegian: Polarjo

Polish: wydrzyk teposterny
Portuguese: mandrião-pomarino / moleiro-do-árctico
Slovak: pomorník stredný
Slovenian: lopatasta govnacka
Spanish: Págalo pomarino
Swedish: bredstjärtad labb
Welsh: Sgiwen Frech

English folkname(s): Pom

More Evidence

More evidence from Conservation Evidence.com

Partners

Birdfacts is based on data collected by volunteers participating in surveys that are organised and funded by BTO, RSPB, Esmée Fairbairn Foundation, JNCC and other partners.

BTO

Esmée Fairbairn Foundation

JNCC

RSPB

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