The effect of different Rice Oryza sativa cultivation methods on nest-site location and nesting success in Black-winged Stilts Himantopus himantopus in reclaimed areas of South Korea

Abstract

Rice Oryza sativa fields are important surrogate habitats for many organisms. We monitored a colony of Black-winged Stilt Himantopus himantopus in rice fields, in the Seosan reclamation area of South Korea, from 1998-2005. Two methods of rice cultivation were employed there 1: aerial seeding on a large scale using planes 2: the traditional method of rice replanting, where rice seedlings are replanted after ploughing. The latter method destroyed all nests and was increasingly used over time as farmland was sold off to private farmers. Most nests were destroyed because the timing of ploughing and replanting overlapped with the nesting period of the Black-winged Stilt. We monitored the break-up of the colony into sub-colonies and single nests, then eventually the failure of the colony. Flooding, during episodes of heavy precipitation resulted in more nest failures than predation. Predation at Black-winged Stilt nests was considered opportunistic with birds the most frequent consumers of eggs. Finally, we make suggestions for future research in reclaimed areas, particularly by using rice fields as more biodiverse habitats.