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

摘要： 目的 了解杭州市2017－2021年蝇种构成、种群密度和季节消长趋势,探讨气象因素对蝇类密度的影响,为蝇类防制提供科学依据。方法 2017－2021年4－11月在杭州市选择居民区、餐饮外环境、绿化带、农贸市场4类生境,采用笼诱法进行蝇密度监测,对获得的数据使用Excel 2019和SPSS 20.0软件进行统计分析。对不同年份、生境间数据差异进行χ²检验和单因素方差分析,对蝇类密度和气象因素进行相关和回归分析。结果 2017－2021年杭州市共布放诱蝇笼4 967个,捕获蝇10 267只,蝇类总密度为2.07只/笼；以麻蝇科蝇种、家蝇、丝光绿蝇和大头金蝇为优势蝇种,占捕获总数的74.00%,其中麻蝇科蝇种密度最高,为0.32只/笼。不同生境中,农贸市场蝇类密度最高,为2.79只/笼,餐饮外环境最低,为1.44只/笼,不同生境间蝇密度差异有统计学意义（F=8.493,P=0.001）。杭州市不同地区中,余杭区蝇类密度最高,建德市蝇类密度最低,各地区蝇类密度差异无统计学意义（F=1.433,P=0.140）。蝇类密度总体的季节消长呈“双峰”,高峰分别出现在6和8月,不同年份蝇类密度季节消长差异无统计学意义（F=0.865,P=0.495）。杭州市蝇类密度与平均气温、平均最高气温、最高气温极值、平均气温≥18 ℃的天数、平均露点温度、降水量、最大单日降水量、平均最低气温和最低气温极值呈现正线性相关；多元逐步回归分析显示,平均最高气温可进入回归方程y=-1.707+0.430x（F=79.701,P<0.001）。结论 杭州市总体上以麻蝇科蝇种为优势蝇种,蝇密度以农贸市场最高,活动高峰期以夏季为主,蝇密度受多种气象因素影响,建议蝇类防制时在其活动高峰期前及早采取综合措施,以控制蝇密度处于不足为害的水平。

关键词: 蝇, 监测, 密度, 季节消长趋势, 气象