Brown-headed Cowbird

Molothrus ater

Introduction

Brown-headed Cowbird is a species that parasitises the nests of other birds in its North American breeding grounds. This Starling-sized bird was added to the British List because of an individual found on Islay, Argyll in April 1988.

Key Stats

Status

Very rare

Weight

48g

Seasonality

BTO Records

15 records

Population and distribution stats for:

No data

No current data

No current data

No data

No current data

No current data

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.

IUCN Red List of Threatened Species (global)

Least Concern

Schedule 1 Licence required (to disturb)*

Birds Directive Annex 1

* 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*

Argyll, 1988

* 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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This species is a rare vagrant and was recorded during Bird Atlas 2007–11 as shown on the map.

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.

Breeding Distribution for Brown-headed Cowbird

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.

Distribution Change

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This vagrant is too rarely reported to map distribution change.

Seasonality

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This species has been too rarely reported to BirdTrack during 2011–22 to properly assess seasonality.

Movement

Information about Brown-headed Cowbird 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 Brown-headed Cowbird, including statistics on nesting, eggs and lifespan based on BTO ringing and nest recording data.

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 Brown-headed Cowbird

Classification and Codes

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Order: Passeriformes
Family: Icteridae
Scientific name: Molothrus ater
Authority: Boddaert, 1783

Euring code number: 18990

Alternate species names

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Catalan: vaquer de cap bru
Czech: vlhovec hnedohlavý
Danish: Brunhovedet Kostær
Dutch: Bruinkopkoevogel
Estonian: piisoniturpial
Finnish: lehmäturpiaali
French: Vacher à tête brune

German: Braunkopf-Kuhstärling
Hungarian: barnafeju gulyajáró
Icelandic: Kúastarli
Italian: Molotro testabruna
Latvian: brungalvas govjputns
Lithuanian: rudagalvis karvapaukštis
Norwegian: Brunhodetrupial

Polish: starzyk brunatnoglowy
Portuguese: chopim-mulato
Slovak: zanášac cierny
Slovenian: rjavoglavi kravar
Spanish: Tordo cabecipardo
Swedish: brunhuvad kostare
Welsh: Aderyn Gwartheg Penfrown

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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