关键词: 蝇, 监测, 密度, 季节消长趋势, 气象

Abstract: Objective To investigate the species composition, population density, and seasonal fluctuation of flies in Hangzhou, Zhejiang Province, China from 2017 to 2021, and explore the impact of meteorological factors on fly density, so as to provide a scientific basis for fly control.Methods From April to November of 2017-2021, fly density was monitored by cage trapping method in four types of habitats in Hangzhou, including residential areas, catering-related outdoor environments, green belts, and farmers’ markets. The obtained data were analyzed using Excel 2019 and SPSS 20.0 softwares. The Chi-squared test and one-way analysis of variance were used to compare the data of different years and habitats. Correlation and regression analyses were performed on fly density and meteorological factors.Results From 2017 to 2021, a total of 4 967 fly traps were deployed in Hangzhou, collecting a total of 10 267 flies, with an overall density of 2.07 flies/cage. The dominant fly species were species of Sarcophagidae, Musca domestica, Lucilia sericata, and Chrysomya megacephala, together accounting for 74.00% of the total number of catches, with the density of Sarcophagidae flies being the highest at 0.32 flies/cage. In different habitats, the density of flies was highest in farmer’s markets at 2.79 flies/cage and lowest in catering-related outdoor environments at 1.44 flies/cage, with a statistical difference in fly density between different habitats (F=8.493, P=0.001). Among different regions of Hangzhou, Yuhang District had the highest fly density, while Jiande had the lowest fly density, with no statistical difference in fly density between regions (F=1.433, P=0.140). The overall seasonal fluctuations of fly density showed a double-peak pattern, with the peaks appearing in June and August, respectively. There was no statistical difference in the seasonality of fly density between different years (F=0.865, P=0.495). The density of flies in Hangzhou showed positive linear correlations with the average temperature, average maximum temperature, extreme maximum temperature, days of average temperature ≥18 ℃, average dew point temperature, precipitation, maximum daily precipitation, average minimum temperature, and extreme minimum temperature. Multiple stepwise regression analysis shows that the mean maximum temperature can enter the regression equation y=-1.707+0.430x (F=79.701, P<0.001).Conclusions In Hangzhou, the density of flies is the highest in the farmers' market, the peak period of activity is mainly summer, and the density of flies is affected by a variety of meteorological factors. It is recommended that comprehensive control measures should be taken as early as possible before the peak period of fly activity to control the fly density at insufficient levels.

Key words: Fly, Surveillance, Density, Seasonal fluctuation, Meteorology