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The effects of habitat fragmentation as a threat to biodiversity are well known; decreased connectivity can potentially influence population processes and dynamics, resulting in smaller, isolated populations that may not function optimally. However, fragmentation may also increase the amount of edge or ecotone habitat available to open country species, benefiting their populations and enabling them to dominate remnant habitats. Noisy miners (Manorina melanocephala) are one such species, occupying eastern‐Australian eucalypt woodlands. They are considered a ‘despotic’ species, in that their presence negatively impacts woodland avifauna biodiversity due to their aggressive exclusion of other taxa from occupied areas. Despite this well‐known impact, little information exists on the patterns of nest‐tree occupancy by noisy miners within eucalypt woodlands. In the current study, we explored the patterns of nest‐tree occupancy by noisy miners across two successive years, aiming to identify preferences for breeding areas relative to vegetation structure. Our results show that both habitat fragmentation and the characteristics of individual eucalypt trees in an area influenced nest‐tree occupancy. Noisy miners constructed nests in trees near the edge of woodland patches more often than expected. Moreover, the nest tree chosen was a eucalypt that was significantly smaller than randomly selected trees from the surrounding area. The results highlight the importance of habitat management measures that may reduce the suitability of woodland patches as nesting sites for this species, in order to mitigate the severe effects of this despotic edge specialist.

Nest-site characteristics and hatching success were studied at a mixed-species colony of Black-winged Stilts Himantopus himantopus and Gull-billed Tern Gelochelidon nilotica in AghGol wetland, Hamedan Province, Iran during the 2008 breeding season. Species-specific preferences and a possible correlation between hatching success and nest location were analysed. Black-winged stilts select significantly closer points to the water edge than random points while the distance to the water edge did not vary between preferred and non-preferred locations for Gull-billed Terns. Plant density was significantly higher in Gull-billed Terns than Black-winged Stilt nest-sites, which also preferred areas of lower plant density. Hatched Gull-billed Tern nests had significantly higher plant density around the nest than failed nests. Overall, hatching success of Gull-billed Tern was higher than that of Black-winged Stilt; mainly because of disturbances resulting from a decrease in the water level.

No abstract

Variations in nest-site parameters were studied at Lake Zarivar, Kurdistan Province, Western Iran in 2007 and 2008. This study was applied for six breeding waterbird species: Great-crested Grebe (Podiceps cristatus), Little Grebe (Tachybaptus ruficollis), Moorhen (Gallinula chloropus), Coot (Fulica atra), Water Rail (Rallus aquaticus) and Whiskered Tern (Chlidonias hybrida). A total of 205 nest-sites were studied in terms of five environmental factors: vegetation density and height, water depth, distance to open water, as well as distance to the nearest nest of the conspecific species were measured. Great-crested Grebes selected areas of deeper waters, possibly to increase feeding efficiency. All species were directly dependent on water for nesting, except for the Water Rail, which established its nest in muddy areas with higher vegetation density and height. Nests were at a higher density for the Whiskered Terns than in other species. Overall, mean water depth at nesting sites was lower in the 2008 breeding season and total breeding population of waterbirds decreased. Evaluating and monitoring of habitat quality of breeding species urges conservation measures with regard to transformations occurring at this freshwater lake ecosystem.