Breeding ecology of the Pied Avocet Recurvirostra avosetta in AghGol wetland, Hamedan Province, Iran

Barati A., Nouri V. S.



Abstract:

The breeding ecology of the Pied Avocet Recurvirostra avosetta was studied during the 2008 breeding season in AghGol wetland, Hamedan province, western Iran. The breeding parameters, i.e. laying date, clutch size, brood size, nest site characteristics, breeding success and nestling body mass at hatching were taken into consideration. Egg laying occurred from 10 May to 9 June. Mean clutch size was 3.13 ± 0.74 (sd) eggs and the mean distance between nests was 2.74 ± 1.01 meters. Nesting occurred in places with vegetation cover of about 40% and at a mean distance of 7.24 ± 2.31 m to water edge. Nests often were built among vegetation, but some occurred on dry mud (25%). Hatching success was 23% and mean net productivity was 0.33 ± 0.19 chicks per nest. The mass of hatchlings was 21.5 ± 3.2 g at the frst day. Whole nest failure from human predation and sheep grazing was responsible for most egg losses. About 75% of the nests failed, being destroyed before hatching. Some conservation measures for this breeding colony are discussed.