Savi's Warbler Breeding in Suffolk

SAVI'S

WARBLER

BREEDING

IN

SUFFOLK

G . J. JOBSON

IT is a pleasure to record that the Savi's warbler has re-established itself as a breeding species in Suffolk after an absence of some eighty years. This is no surprise after the establishment of a breeding colony in Kent since at least 1960 (Pitt, 1967), and singing forerunners of this northwards expanding species in several other English counties during the last decade and in Suffolk in 1964 and since 1968 (Harber, 1965; Smith, 1969).

It was in May, 1968, that I first heard a Savi's warbler at Walberswick. In 1969 there were two reeling birds there from May to July, breeding was not proved and, perhaps surprisingly, it proved absolutely impossible to obtain a view of the birds. My next encounter in 1970 with Savi's warbler came earlier than expected. Reeling had started by 17th April and continued until August, and the signs were not only indicative of breeding but of being double brooded as well.

In mid-summer I obtained special permission to visit one of the sites. This was a Clearing in the reeds (Phragmites) surrounding two small pools connected by a ditch. It seemed to offer good possibilities, you could stand motionless on one side of the pool and watch reed warblers, etc., working their way along the ditch from the other pool. T h e male Savi's warbler at this site reeled in the dense reeds surrounding the pool, tantalisingly close, yet invisible. However, by making "clucking" noises at it, the bird slowly climbed to the top of the reeds to satisfy its curiosity to see what was going on. It reeled in fĂźll view for several minutes and even the local water-rail came out to see what was going on!

By the end of June there were just a few short bursts of reeling, but by mid-July the grasshopper and Savi's warblers had recommenced long and lengthy reeling indicating second broods.

Finally two fully fledged juveniles were trapped later in the summer

by D. J. Pearson whilst ringing young reed and sedge warblers.

T h e Savi's warbler is superficially like a reed warbler. It is a uniformly dark brown above, unstreaked, and unspotted. T h e underparts are whitish and a good point is the more pronounced white throat. Indeed in one bird I saw, this was very clearly defined with a border almost reminding me of a scrub warbler.

T h e bill is not as long and dagger-shaped as the reed warbler, but is still quite stout. T h e r e is a faint eyestripe and the bird has a very long, dark brown, fan-shaped tail which in flight gives the bird a very long-tailed appearance. When agitated the bird will sit at the top of the reeds uttering a "chick" note with a lot of tail flicking in the manner of a blackbird. T h e r e is also a harsh chatter

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Suffulk Natural History, Vol. 15, Part 5

which is surprisingly starling like. By far the best means of identification though, is the song. The grasshopper warbler's reel is lighter, pitched higher, wavers and each note is clearly defined.

The Savi's is pitched considerably lower, and most important of all, is a rapid reel (even to being described as more like a buzz, which is fair comment). If you are near enough you can also hear the "tic, tic, tic" which immediately proceeds and merges with the reel. This is diagnostic of this species.

Possibly it is only a matter of time now before this species becomes a reasonably common breeding bird in Suffolk in various reed beds, large or small, that Stretch along the Suffolk coast from Lowestoft to Shingle Street, as well as inland localities. To obtain a view, crashing about in the reeds is a fruitless manoeuvre and the odds favour the person who is Standing motionless on the reed bed edge.

It is intriguing to think what bird watching may be like in Suffolk by the year 2,000. Will serins be singing in country gardens, purple herons and little bitterns breeding, will great reed warblers be reasonably common and will Cetti's warblers be competing for breeding sites with the last few remaining nightingales?

References Harber, D . D . (1965). Report on rare birds in Great Britain in 1964.

British Birds 58, 365.

Pitt, R. G. (1967). Savis Warbier breeding in Kent. British Birds 60, 349.

Smith, F. R. (1969). Report on rare birds in Great Britain in 1968.

British Birds 62, 478.

Scientific n a m e s of birds Purple heron Little bittern Water-rail Blackbird Nightingale Cetti's warbler Grasshopper warbler Savi's warbler Great reed warbler Reed warbler Sedge warbler Starling Serin

d in text Ardea purpurea Ixobrychus minutus Rallus aquaticus Turdus merula Luscinia megarhynchos Cettia cetti Locustella naevia Locustella luscinioides Acrocephalus arundinaceus Acrocephalus scirpaceus Acrocephalus schoenobaenus Sturnus vulgaris Serinus canarius

G. J. Jobsem, 49 St. George's Road, Felixstowe, Suffolk.