Category
A
Status
Scarce
Breeding status
First Record
1970
Last Recorded

Aquatic Warbler Acrocephalus paludicola


Aquatic Warbler photographed at Claire Mare [CLA] on 17/8/2013. Photo: © Michelle Hooper
  Aquatic Warbler photographed at Claire Mare [CLA] on 17/8/2013 Photo: © Michelle Hooper (visit site)

The Aquatic Warbler breeds in the mid-latitudes of central and eastern Europe. Significant populations occur in the marshes of Poland, Belarus and the Ukraine. After breeding, the birds undergo a westerly migration, pass through the wetlands of north-western Europe before turning in a southerly direction to wintering areas in Africa. Most records in north-west Europe are of juveniles and it is likely that adults either migrate in much longer hops or have a slightly different migration route. The exact wintering areas were unknown but large numbers have recently been found wintering in the Senegal River catchment. In spring few are in north-west Europe and it is likely that birds migrate in a smaller number of longer hops and bypass the wetlands used on autumn migration.

The Aquatic Warbler is the only globally-threatened bird to regularly occur in the Channel Islands and, as such, some of the islands' wetlands are of international significance. Aquatic Warblers are cryptic, preferring dense reed and especially low sedge beds where they tend to forage in lower layers of vegetation. They are almost entirely found in the Bailiwick on autumn migration (there are only two spring records) and there are very few visual records - most come are from ringers operating in the islands' reedbeds.

The Bailiwick is on a regular migration route for this species and birds pass through the islands throughout August and the first half of September. Passage peaks in the second half of August with a median date of 20 August, (mean 20 August). The latest, at La Claire Mare, occurred on 18 September 1996. Ringing in reedbeds is a seasonal activity and by the beginning of September ringing effort is reduced and it is unlikely that further records would occur much beyond the first week of September given past and current ringing patterns. All but two records from Guernsey are of trapped birds. One was seen in a patch of low scrub at Pleinmont between 3 and 5 September 1994 and the only other sight record of a bird at the Marais Nord on 25 April 1997 is also one of only two Channel Island spring records [ACCEPTED?].

Most records are of single birds but on several occasions more than one bird has been caught at La Claire Mare. An impressive series of records occurred at Les Bordes (a field adjoining La Claire Mare) during August 1977. Two birds were caught on Saturday 13th August and a further bird the following day. The next weekend, an incredible 8 birds were trapped on Saturday 20th August and a further 2 birds the next day on 21st. This amazing series of records was based around just two weekends ringing. In subsequent years, this total has not been surpassed but birds are now recorded almost annually and records of multiple birds have been recorded four times at La Claire Mare: two birds were trapped on 27 August 1980, 19 August 1980, 19 August 1997 and 17 August 1998.

There are records of Aquatic Warblers from all the major island wetland sites but the low lying marshy area around L'Erée is most preferred area. The earlier series of records from this area refer to Les Bordes which is a field containing sparse reeds and dense sedge beds adjacent to the current Claire Mare Nature Reserve. Since then records refer to La Claire Mare which is dominated by Phragmites reedbed. The majority of the records of this species are from this site, despite effort being put into ringing the other reedbeds. Aquatic Warblers are known to prefer short stands of Juncus & Glyceria rather than large areas of tall reed and the L'Erée area is the only wetland habitat on Guernsey that has this kind of habitat.

One of the conservation measures proposed for this species is to maintain a suitable network of sites and the marshy areas at L'Erée are an important component in that network. Virtually all sites at which Aquatic Warblers have been recorded at in Guernsey are protected.



View all photos (14)
Aquatic Warbler photographed at Claire Mare [CLA] on 17/8/2013. Photo: © Michelle Hooper
Aquatic Warbler photographed at Claire Mare [CLA] on 17/8/2013. Photo: © Michelle Hooper (visit site)

Aquatic Warbler photographed at Claire Mare [CLA] on 17/8/2013. Photo: © Michelle Hooper
Aquatic Warbler photographed at Claire Mare [CLA] on 17/8/2013. Photo: © Michelle Hooper (visit site)

Aquatic Warbler photographed at Claire Mare [CLA] on 2/8/2014. Photo: © Christopher Mourant
Aquatic Warbler photographed at Claire Mare [CLA] on 2/8/2014. Photo: © Christopher Mourant (visit site)

Aquatic Warbler photographed at Claire Mare [CLA] on 9/8/2015. Photo: © Chris Mourant
Aquatic Warbler photographed at Claire Mare [CLA] on 9/8/2015. Photo: © Chris Mourant (visit site)

Aquatic Warbler photographed at Claire Mare [CLA] on 17/8/2013. Photo: © Mark Guppy
Aquatic Warbler photographed at Claire Mare [CLA] on 17/8/2013. Photo: © Mark Guppy (visit site)

Aquatic Warbler photographed at Claire Mare [CLA] on 16/8/2010. Photo: © Chris Mourant
Aquatic Warbler photographed at Claire Mare [CLA] on 16/8/2010. Photo: © Chris Mourant (visit site)

Aquatic Warbler photographed at Claire Mare [CLA] on 2/8/2014. Photo: © Christopher Mourant
Aquatic Warbler photographed at Claire Mare [CLA] on 2/8/2014. Photo: © Christopher Mourant (visit site)

Aquatic Warbler photographed at Claire Mare [CLA] on 5/9/2004. Photo: © Jamie Hooper
Aquatic Warbler photographed at Claire Mare [CLA] on 5/9/2004. Photo: © Jamie Hooper (visit site)

Aquatic Warbler photographed at Claire Mare [CLA] on 9/8/2015. Photo: © Phil Atkinson
Aquatic Warbler photographed at Claire Mare [CLA] on 9/8/2015. Photo: © Phil Atkinson (visit site)

Aquatic Warbler photographed at Claire Mare [CLA] on 0/8/2003. Photo: © Bob Murphy
Aquatic Warbler photographed at Claire Mare [CLA] on 0/8/2003. Photo: © Bob Murphy (visit site)

Aquatic Warbler photographed at Claire Mare [CLA] on 17/8/2013. Photo: © Michelle Hooper
Aquatic Warbler photographed at Claire Mare [CLA] on 17/8/2013. Photo: © Michelle Hooper (visit site)

Aquatic Warbler photographed at Claire Mare [CLA] on 17/8/2013. Photo: © Michelle Hooper
Aquatic Warbler photographed at Claire Mare [CLA] on 17/8/2013. Photo: © Michelle Hooper (visit site)

Aquatic Warbler photographed at Claire Mare [CLA] on 16/8/2010. Photo: © Chris Mourant
Aquatic Warbler photographed at Claire Mare [CLA] on 16/8/2010. Photo: © Chris Mourant (visit site)

Aquatic Warbler photographed at Claire Mare [CLA] on 17/8/2013. Photo: © Michelle Hooper
Aquatic Warbler photographed at Claire Mare [CLA] on 17/8/2013. Photo: © Michelle Hooper (visit site)

 


View database records (27)
Aquatic Warbler Claire Mare 19/8/1993 1
Aquatic Warbler Claire Mare 19/8/1993 1
Aquatic Warbler Claire Mare 29/8/1993 30/8/1993 1
Aquatic Warbler Pleinmont 3/9/1994 5/9/1994 1
Aquatic Warbler Claire Mare 5/8/1995 1
Aquatic Warbler Claire Mare 21/8/1996 1
Aquatic Warbler Claire Mare 18/9/1996 1
Aquatic Warbler Marais Nord/Vale Marais 25/4/1997 1
Aquatic Warbler Claire Mare 19/8/1997 2
Aquatic Warbler Claire Mare 20/8/1997 1
Aquatic Warbler Claire Mare 21/8/1997 1
Aquatic Warbler Grands Marais/Pré 7/9/1997 1
Aquatic Warbler Claire Mare 17/8/1998 2
Aquatic Warbler Claire Mare 26/8/1999 1
Aquatic Warbler Claire Mare 28/8/1999 1
Aquatic Warbler Claire Mare 30/8/1999 1
Aquatic Warbler Claire Mare 7/8/2000 1
Aquatic Warbler Reservoir 7/8/2000 1
Aquatic Warbler Claire Mare 22/8/2003 1
Aquatic Warbler Claire Mare 9/8/2005 1
Aquatic Warbler Claire Mare [CLA] 16/8/2010 1
Aquatic Warbler Claire Mare [CLA] 11/8/2013 1
Aquatic Warbler Claire Mare [CLA] 17/8/2013 1
Aquatic Warbler Claire Mare [CLA] 2/8/2014 1
Aquatic Warbler Claire Mare [CLA] 8/8/2015 1
Aquatic Warbler Claire Mare [CLA] 9/8/2015 1
Aquatic Warbler Claire Mare [CLA] 9/8/2015 1