Savi’s Warbler (Locustella luscinioides)

In contrast to the Grasshopper or River Warbler, the Savi’s has a well defined and somewhat restricted habitat. It mainly occurs in large to very large reedbeds, especially mature ones with lots of layers of growth. It avoids reed monocultures, however, preferring an understorey of sedge and other waterside plants where the birds can feed, and here the population is at its densest. Some populations are tolerant of alders and other trees growing nearby.

Where they occur Savi’s Warblers are usually found in bulk, with many birds sharing the same reeds at high density. The males, however, are extremely territorial, and often sing at each other, not far apart, across their invisible boundaries. These borders are seldom crossed, although later in the season the birds often seem to shift about, and may alter their boundaries for second broods, making them notoriously difficult to census. The song is typical for the group, sounding more insect-like than bird-like (it is almost identical to the stridulation of the Roesel’s Bush-Cricket), but it also sounds distinctly like a miniature drill.

Savi’s Warblers obtain most of their food deep down in the vegetation close to the water, or even from the surface. The latter has been confirmed by the presence of significant numbers of aquatic larvae and water-snails in the diet. As a rule Savi’s Warblers take fewer fast moving prey than their reed bed-fellows, the Reed Warblers, and they creep rather than flutter about to take it.