Warblers

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seasonal warblers

Often so hard to see in a density of stems, thickets or layers of foliage, but giving voice to the unseen space within. Back off a step, hold still indefinitely and maybe the voice will emerge onto some prominent twig to deliver in the open.

May is the big month for birdsong, when hordes of summer migrants appear with the emergent foliage to settle with all our resident birds. They may wander for a while. So it’s typified by the warblers, itinerant seasonal musicians, all in full voice in May, drawn to sing by the sun’s warmth, when their insect fuel is humming in abundance.

Warblers are the essence of birdsong – generally pretty drab birds, but notable for their voices and ways of singing. There are a few examples here of some of the more interesting singers. Each genus has its own sound or style, within which species have developed their own particular songs and ways of singing.


Locustella

Grasshopper Warbler : Savi’s Warbler : River Warbler
Locustella warblers tend to reel like grasshoppers or crickets, and, in the case of Grasshopper Warbler or Savi’s, can easily be overlooked as such. River Warbler, found in eastern Europe, has a shuffling rhythm to the reel, sounding like a giant Common Green Grasshopper (or an old-style sewing machine – though I doubt too many people remember these now); occasionally males turn up in Britain in Spring, settle in and sing. When groppers sing, their whole body vibrates with the physical effort. In rank herbage and reedbeds.

Grasshopper Warbler Locustella naevia (pictured)
Recorded: Northumberland 9.5.2007 7:30pm


Acrocephalus

Sedge Warbler : Marsh Warbler : Reed Warbler

Acrocephalus warblers chatter, often at astonishing speed, and have the ability to voice both rough grating notes and sweet pure or liquid notes. They’re given to mimicry of other species. Song tends to be in verse-like passages, though these can be prolonged, often 15-25 seconds; in the case of Reed Warbler, it’s a continuous and regular stream. In reedbeds and marshy scrub.

Sedge Warbler Acrocephalus schoenobaenus (pictured)
Recorded: Northumberland 10.7.2005 5:00am

Marsh Warbler Acrocephalus palustris
Recorded: Biebrza, Poland 2.6.2004 2:30pm


Hippolais

Icterine Warbler : Melodious Warbler

Hippolais warblers are also chatterers and given to looping a sequence like a scratched vinyl record. Some species are exceptional mimics and show many similarities of style with the Acrocephalus warblers. None of the Hippolais species are regular breeders in Britain and Ireland, though many crop up as vagrants at times of migration and there have been instances of Icterine Warbler breeding in Scotland in recent years. In trees and shrubs.

Icterine Warbler Hippolais icterina
Recorded: Biebrza, Poland 31.5.2002 4:30am

Pictured: Eastern Olivaceous Warbler Hippolais pallida (elaeica).


Sylvia

Dartford Warbler : Lesser Whitethroat : Whitethroat : Garden Warbler : Blackcap

Sylvia warblers are sometimes referred to as typical warblers and encompass some of the most admired singers. Song styles vary from short chattery verses, generally more fluid than Acrocephalus to sustained passages of more melodic, clear-toned notes. Many species incorporate mimicry, though less obviously than the Acrocephalus species. In trees, bushes and heath.

Blackcap Sylvia atricapilla (pictured)
Recorded Northumberland 16.6.2008 6:00am


Phylloscopus

Wood Warbler : Chiffchaff : Willow Warbler

Phylloscopus warbler songs vary from extended trills to rather simple verses. Notes tend to be slurred (though brief, sliding in pitch) or liquid-sounding. Chiffchaff songs cycle round a two- or three-note motif, where the very similar-looking Willow Warbler gives a short, rhythmically-phrased cascade of notes. These are birds that hunt through the leaf foliage, though tend to nest on the ground, and usually sing while foraging, pausing every little while to deliver a verse.

Wood Warbler Phylloscopus sibilatrix
Recorded: West Inverness-shire 2.5.2010 6:40am

Willow Warbler Phylloscopus trochilus
Recorded: West Inverness-shire 2.5.2010 5:30am

All recordings from Sennheiser MKH30/40 ms set-up.


why warblers

From Simms’ British Warblers: ‘The origin of the word seems to be from the Middle English werbelen or the Old French werbler – to sing or play on a musical instrument. The Dutch wervelen appears to be its counterpart in Holland.’

All these warblers used to be grouped together as the family Sylviidae (sometimes referred to as ‘old world warblers’ to distinguish them from the unrelated group referred to in north America as warblers); recent proposals are that each of these genera belong to their own families, except Acrocephalus and Hippolais, which share a lineage.