Ornis Hungarica. vol.8 Suppl. 1.. (1998) p.59-68.
Spatial pattern of breeding habitats of three wader species at two saline lakes
The saline lakes are one of the most important breeding sites for waders on the Great Hungarian Plain. I monitored the breeding populations of 3 waders, the Lapwing (Vanellus vanellus), Avocet (Recurvirostra avosetta) and Redshank (Tringa totanus) at the Lake Kelemen and Lake Zab in the Kiskunság National Park by territory mapping over five years. There are four main macro-habitat patterns in the shore-line of the saline-alkaline lakes: shallow water, sea club-rush (Bolboschoenus maritimus). saline puddles, and dry meadows. These patterns were identified from vegetation maps and aerial photos. The location of wader nests were also mapped. On the basis of these two maps, the areas of the macro-habitat patterns (ha) within 200 in of tile nests were calculated. The distribution patterns of averages and variances were analysed by F and t-tests (p<0.05). Relation between patterns and density was investigated by correlation analysis. The macro-habitat preferences of Lapwing and Redshank were similar. Thiese, in decreasing order were: 1. saline puddles, 2. dry meadow. 3. sea club-rush, 4. shallow water within 200 meters around the nests. Lapwing's and Redshank nests were often found a few meters from each other in the preferred habitats. The density of nests was related to the expansion of saline puddles at the lake shores. The Avocet's macro-habitat preference was similar , but correlations between the density and patterns showed different preference order. The tipically colonial-breeditig Avocet's macro-habitat preferences were: 1. saline puddles. 2. sea club-rush. 3. dry meadow. 4. shallow water within 200 meters around the nests (colony). The sea club-rush zone is preferred by waders but not for breeding. This plant species is expensive and may need active management to preserve the optimal habitat structure I or waders in the breeding season.