Objective Master the population composition and seasonal abundance of the flies to provide scientificevidences for formulating vector control strategies by the government. Methods Monitoring the populations of flies fromMarch to December in 2006-2016 in different environments with brown sugar and vinegar, to analyze the density andcomposition of flies. Results Chrysomya megacephala, Musca domestica, Lucilia sericata, and L. cuprina were thepredominant species of flies in Ningbo area, which accounted for 80....