Investigation On Interception Of Extoic Insects At Qinhuangdao Port

The purpose of this paper is to provide a reliable reference for the prevention and control of insects carried by foreign ships at Qinhuangdao Port.Based on the statistics and analysis of the species of alien insects intercepted at Qinhuangdao Port in 2017,565 species of insects were found in 2017,involving 8 orders of insects.The first three insects with higher interception frequency were Coleoptera,Diptera and Hemiptera.In order to better understand the survival characteristics of insects carried by foreign ships,through taking some Diptera insects carried by more than 2000 foreign ships at Qinhuangdao Port in recent years as specific research objects,combining with the work of consulting data,literature and visits,it was found that there were mainly four types of Diptera insects: mosquitoes,flies,midges and blackflies.Among them,19 species of mosquitoes were found in 1 family,4 subfamilies and 1 species of flies were found.There are 46 species in 8 genera,11 species in 3 genera and 1 family in midges and 7 species in 1 genera and 1 family in Simulidae,totaling 83 species.Based on the investigation of the distribution characteristics of mosquitoes and flies on inbound ships and the seasonal variation of population growth and decline,it was found that mosquitoes mainly inhabit specific open places outside the ship's living areas,and with the increase of temperature and humidity,the population density increases significantly and reaches its peak.Different flies choose different habitats on ships.For example,Musca domestica and Aldrichina.grahami usually take the garbage cans as their main places of activity,Calliphoridae often take the cable pile as their main place of activity,and Megacephala Chrysomya can be found resting at the rear deck railings and other places.Through the investigation of the law of fly population growth and decline,it is found that the population density increases with the temperature.The population density increased gradually,but decreased significantly with the increase of humidity,which was inversely proportional to humidity.By classifying the countries and regions of origin of the intercepted Diptera insects,it was found that there were 14 countries and regions involved,among which the top five countries carrying the most species of Diptera insects were 29 species in Korea,13 species in Australia,11 species in Japan,10 species in Taiwan,China and 9 species in Southeast Asia.The composition of fly and mosquito populations,the variation of population density and distribution in Qinhuangdao Port were investigated.The population composition,habitat distribution and seasonal variation of mosquitoes and flies in the harbor area were basically mastered.It was found that the population growth and decline of mosquitoes and flies were basically consistent with the results of ship survey.The population density of mosquito larvae was proportional to the water temperature in breeding area.When the water temperature reached 20 C,larval activity could be found in breeding area.When the water temperature reached 28 C,the activity of larvae was the highest,and the population density reached the peak at the same time.Later,with the temperature gradually decreasing,the larval population density could be found in breeding area,reduce until it disappears.