The Uskmouth Savi’s Warbler

A Savi’s Warbler (Locustella luscinioides) at the RSPB’s Uskmouth Nature Reserve has now entered the third week of its stay. The bird was found by Mathew Meehan and is the first record for Gwent. It is holding territory in a small strip of reedbed in the centre of the reserve, flanked on one side by a track and on the other by open water, so (unusually for this species) it is quite easy to observe. If visiting, please keep to the paths: as well as the Savi’s Warbler, nesting Bearded Tits (Panurus biarmicus) and Cetti’s Warblers (Cettia cetti) are present in the same area.

Savi’s Warbler, 1 June 2014, Uskmouth Nature Reserve, Martyn Hall (www.martynhallphotography.com)

If the physical appearance of Savi’s Warbler is a little dull, its song certainly isn’t: it sounds like a loud, prolonged cricket. I emphasise loud: on my first visit, I could hear the bird from at least 100 metres away as I approached. Click here to listen to a recording of the Uskmouth bird by Darryl Spittle.

Savi’s Warbler is at the northwestern end of its world range in Britain, and numbers have fluctuated considerably since it was first discovered here in the early 19th Century. Back then, it bred in Norfolk and Cambridgeshire, but with drainage of the fens, this population died out by around 1850. It remained a rare migrant for the next 100 years, but then established a breeding population again, initially in Kent, then in Norfolk, Suffolk and a few other southern and eastern counties, although still in tiny numbers: the peak population was of c.30 singing males at a total of c.15 sites in 1977-1980. Numbers have since declined, to the point where ten singing males constitutes a good year.

Most of our local birds have occurred on the Somerset Levels, where around a dozen have occurred, with two clusters of records: four birds at the gravel pits around Bridgwater between 1970 and 1988, and five birds in the Ham Wall/Meare Heath area between 2005 and 2010. Chew Valley Lake has had four, the last of which was in 2001. In Gloucestershire there have been just two: at Frampton in spring 2001, and at Coombe Hill Meadows in 2013. Wiltshire has also had just two, at Coate Water, Swindon in May 1965, and at the Cotswold Water Park in 2006. Almost all of these birds have been singing males in spring, so no doubt other individuals have occurred undetected. With the increase in records from the Somerset Levels in the last decade, there’s perhaps a good chance that Savi’s Warbler will become a regular breeding bird here one day.