31 Mar 2015

Common Grasshopper Warbler trapped & ringed – Sabkhat Al Fasl

Whilst ringing at Sabkhat Al Fasl 27 March 2015 we trapped and ringed a Common Grasshopper Warbler a species that is a rare passage migrant to the Eastern Province of Saudi Arabia where they occur on passage from early March to April and again in September. Common Grasshopper Warbler was not mentioned by Symens & Suhaibani 1996 in their list of birds seen at this location and appears to be a first record for the site. The subspecies we trapped was one of the western races, either nominate Locustella naevia naevia or Locustella naevia obscurior due to the wing length of 64 with eastern birds having wing lengths of less than 60. It was also a very well marked bird with plenty of obvious streaks down the flank making it superficially look a little like a Lanceolate Warbler. Common Grasshopper Warbler Locustella naevia naevia breeds in Europe from southern Scandinavia and southern Finland south to Britain and Ireland, northwest Iberia, east to western European Russia and Ukraine and winters in west Africa whilst Locustella naevia obscurior breeds Caucasus mountains south to northeast Turkey and Armenia with non-breeding birds moving to northeast Africa. These birds have a darker colour than eastern birds that have a distinctly paler and more olive-grey ground-colour with L. n. obscurior differing from nominate naevia by being slightly more olive with heavier, blacker, and more contrasting spots on upperparts; feather-fringes more olive, less brown, sandy-grey rather than olive-brown when worn; flank more tinged rusty-cream. Birds are difficult to positively assign to race due to individual variation. This is only the third time I have seen the species in Saudi Arabia with the first a bird on my local patch at Dhahran on 1 April 2012 and the second one in a pivot irrigation field near Nayriyyah 14 March 2013.
Common Grasshopper Warbler

Common Grasshopper Warbler

Common Grasshopper Warbler

Common Grasshopper Warbler

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