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Background:The Hair-crested Drongo (Dicrurus hottentottus) exhibits a unique nest-dismantling behavior after the fledging of the young. One hypothesis explaining this behavior is dismantling one's own nest may reduce potential competition for nest sites in the following breeding season because suitable breeding habitat might be limited, and sites are often reused.Methods: By comparing the habitat features at nest and random locations, we determined the nest habitat preference of the Hair-crested Drongo within Dongzhai National Nature Reserve, Henan, China. We also compared habitat features with nesting success to determine if any trends could be detected. Results:We found that nest tree height, diameter at breast height, live crown ratio, tree rank, and presence of overstory were significantly higher at nesting locations than random locations; slope, leaf litter cover percentage and depth, presence of understory and midstory, and number of trees per hectare were significantly lower at nest sites than random sites. Drongos preferred to use some tree species, such as Metasequoia glyptostroboides, Castanea mollissima, and Pterocarya stenoptera for nesting. Failed nests were often associated with habitat with higher percentage of leaf litter on the ground. Conclusion:Our data support that selection of nest sites does occur for this species at this site and therefore support the hypothesis that breeding habitat limitation could be one of the driving forces for the development of the nestdismantling behavior in this species.

Ectoparasites and other invertebrates are known to play a role in bird behavior and in evolutionary adaptations such as preening and foraging strategies. We conducted an exploratory study by macro-and microscopically evaluating the nests of Hair-crested Drongos (Dicrurus hottentottus) at Dongzhai National Nature Reserve, Henan Province, China in 2011 to determine if there was a presence of invertebrates. We developed a modified funneling technique to collect invertebrate samples and reduce contamination from outside sources in a field setting. We found several species of ectoparasites (lice and ticks) and other invertebrates (springtails and rove beetles) within the nests. Our findings warrant further investigation as to whether or not the presence of invertebrates in the nests of Hair-crested Drongos plays a role in the adaptation of the unique nest dismantling behavior exhibited by this species.