Abstract
As part of the environmental impact assessment of public works (e.g., road, dam, rail, and power plant construction projects), raptors are often surveyed as environmental indicator species, and environmental conservation measures (ECM) for raptors are often required when construction projects are in progress. However, the effects of ECM have not been analyzed statistically. We aggregated the cases of ECM exhaustively in nationwide road projects between 2009 and 2012, and analyzed the effects of ECM based on 787 nesting successes/failures of three rare raptors (Northern Goshawk, Grey-faced Buzzard and Mountain Hawk-eagle) using the meta-analysis approach. The results showed that there was no significant difference between the nesting success rates of each species before and during roadwork projects, and that there was no downward trend with decreasing distance to the roadwork zones. ECM notably increased the nesting success rate of the Goshawk. Thus, ECM succeeded in maintained the nesting success rates of three rare raptors to a level commensurate with levels prior to roadwork projects, and efficient and effective ECM should be continued in the future.
