21-5-2017 PEGO MARJAL, ALICANTE - GREAT REED WARBLER (Acrocephalus arundinaceus)

The great reed warbler (Acrocephalus arundinaceus ) is a Eurasian passerine in the genus Acrocephalus.

The genus name Acrocephalus is from Ancient Greek akros, "highest", and kephale, "head". It is possible that Naumann and Naumann thought akros meant "sharp-pointed". The specific arundinaceus is from Latin and means "like a reed", from arundo, arundinis, "reed".

It used to be placed in the Old World warbler assemblage, but is now recognized as part of the marsh and tree-warbler family (Acrocephalidae). Great reed warblers are medium-sized birds and are the largest of the European warblers. They breed throughout mainland Europe and the west Palearctic and migrate to sub-Saharan Africa in the winter. Great reed warblers favour reed beds as their habitat during breeding months, while living in reed beds, bush thickets, rice fields, and forest clearings during the winter. Great reed warblers exhibit relatively low sexual dimorphism, and both genders of the species are similar in appearance. This species mates both polygynously and monogamously.

The thrush-sized warbler is one of the largest species of the former family, the Old World warblers and it stands as one of the largest species in the family Acrocephalidae. It measures 16–21 cm (6.3–8.3 in) in length, 25 to 30 cm (9.8 to 11.8 in) in wingspan and weighs 22 to 38 g (0.78 to 1.34 oz). The adult has unstreaked brown upperparts and dull buffish-white chin and underparts. The forehead is flattened, and the bill is strong and pointed. It looks very much like a giant Eurasian reed warbler (A. scirpaceus ), but with a stronger supercilium.

The sexes are identical, as with most old world warblers, but young birds are richer buff below.

The warbler's song is very loud and far-carrying. The song's main phrase is a chattering and creaking carr-carr-cree-cree-cree-jet-jet, to which the whistles and vocal mimicry typical of marsh warblers are added.