Blyth's Reed Warbler

Acrocephalus dumetorum

Introduction

Closely resembling a Reed Warbler and best identified by its song, Blyth's Reed Warbler breeds in scrubby habitats, from Finland east to central Russia and Mongolia.

Wintering in India, Bangladesh and Myanmar, Blyth's Reed Warbler is a scarce visitor to Britain. Most records fall in September or October, and about half of these come from the Northern Isles. Following breeding range expansion in Europe, and increasing numbers of singing males in spring, a pair successfully bred in Scotland in 2024.

Key Stats

Status

Very rare

Weight

12g

Seasonality

<1%

BTO Records

1.7k 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

Open Close

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

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

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

Population Size

Open Close

BOU Category

Source

First Record*

Fair Isle, 1910

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

Population Change

Open Close

Population trends of this scarce species are not routinely monitored.

Distribution

Open Close

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

Occupied 10-km squares in UK

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

No. occupied in winter

% occupied in winter

0.03%

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.

Winter Distribution for Blyth's Reed Warbler

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

Breeding Distribution for Blyth's Reed Warbler

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

Open Close

This vagrant is too rarely reported to map distribution change.

Seasonality

Open Close

Blyth's Reed Warbler is a rare vagrant. In recent years some males have held territory in late spring but most birds are recorded in September and October.

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 Blyth's Reed Warbler movements and migration based on online bird portals (e.g. BirdTrack), Ringing schemes and tracking studies.

Britain & Ireland movement

Open Close

View a summary of recoveries in the Online Ringing Report

Foreign locations of birds ringed or recovered in Britain & Ireland

Dots show the foreign destinations of birds ringed in Britain & Ireland, and the origins of birds ringed overseas that were subsequently recaptured, resighted or found dead in Britain & Ireland. Dot colours indicate the time of year that the species was present at the location.

Winter (Nov-Feb)
Spring (Mar-Apr)
Summer (May-Jul)
Autumn (Aug-Oct)

Foreign locations of birds ringed or recovered in Britain & Ireland

European movements

Open Close

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.

The Eurasian-African Migration Atlas shows movements of individual birds ringed or recovered in Europe. See maps for this species here.

Biology

Lifecycle and body size information for Blyth's Reed Warbler, including statistics on nesting, eggs and lifespan based on BTO ringing and nest recording data.

Survival and Longevity

Open Close

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.

View number ringed each year in the Online Ringing Report.

Classification, names and codes

Taxonomy, names and species codes for Blyth's Reed Warbler

Classification and Codes

Open Close

Order: Passeriformes
Family: Acrocephalidae
Scientific name: Acrocephalus dumetorum
Authority: Blyth, 1849

BTO 2-letter code: DU
BTO 5-letter code: BLRWA
Euring code number: 12480

Alternate species names

Open Close

Catalan: boscarla dels matolls
Czech: rákosník pokrovní
Danish: Buskrørsanger
Dutch: Struikrietzanger
Estonian: aed-roolind
Finnish: viitakerttunen
French: Rousserolle des buissons

German: Buschrohrsänger
Hungarian: berki nádiposzáta
Icelandic: Elrisöngvari
Irish: Ceolaire Blyth
Italian: Cannaiola di Blyth
Latvian: krumu kaukis
Lithuanian: sodine nendrinuke
Norwegian: Busksanger

Polish: zaroslówka
Portuguese: felosa-das-moitas
Slovak: trsteniarik krovinový
Slovenian: robidna trstnica
Spanish: Carricero de Blyth
Swedish: busksångare
Welsh: Telor Cyrs Blyth

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.