The birds of Pasvik / E. I. Khlebosolov, O. A. Makarova, O. A. Khlebosolova [et al. ; English transl. Nikita Chernetsov]. - Ryazan : Golosgubernii, 2007. - 175 с. : ил., портр.

р 0,30 р - 0 , 3 2 - Р 0,22 0,40 Figure 3.24. Succession and frequency o f foraging manoeuvres used by Song Thrushes: H — hop; P — pick; To — turning over dry leaves; S —searching for prey. N is the n um ­ ber o f successions o f foraging manoeuvres. Numbers show the frequency o f foraging m anoeuvres after the preceding ones (Baranovsky et al., in press). P N = 456 3 .2 . Passerine communities of swamps and coastal scrub The ecological group of passerines o f swamps and coastal scrub includes the Yellow Wagtail, Meadow Pipit, Bluethroat, Reed Bunting, Little Bunting and Sedge Warbler. Most these species are the inhabitants o f more southern areas and occur there in intrazonal habitats: meadows, wetlands, shores o f rivers and lakes. They penetrate far to the north along the intrazonal habitats. Therefore, the study o f the structure o f ecological niches and mechanisms o f ecological segregation o f these species is o f considerable interest both for the understanding o f formation o f passerine communities o f Pasvik and for the analysis o f fo rmation o f intrazonal avian communities in general. 3 .2 .1 . Birds of swamps The most typical wetland passerines o f Pasvik are the Yellow Wagtail and Meadow Pipit. Yellow Wagtail most frequently occurs in peat bogs with carr and in wet lake depressions. The breeding density o f this species in optimal habitats may reach 150 pairs* k n r 2 (Annals o f Nature ... 2005b). Not all bog areas are suitable for this species. Yellow Wagtails forage in wet moss and sedge patches and avoid high places covered by green moss, lichens, crystal tea ledum, red bilberry, black crowberry, andromeda and other subshrubs. The highest numbers o f these birds are recorded where wet moss and sedge cover continuous areas. In such places breeding territo­ ries o f Yellow Wagtails have an average area o f ca. 0.5 ha. Where suitable wet moss and sedge areas are alternated with dry hills, breeding territories are larger, exceed­ ing 1 ha, and breeding density is ca. 60 p a ir s * k n r2 (Fig. 3.25). 144