Distribution and population density of Halyomorpha halys (Stål, 1855) (Hemiptera: Pentatomidae) in Black Sea Region of Türkiye

: Brown marmorated stink bug (BMSB), Halyomorpha halys , is a polyphagous invasive pest whose spread and damage are increasing with global commercial activities. In this study, following the invasion of Black Sea Region in 2018, spread, population density and change of the pest were investigated in the years 2019, 2020, and 2021, possible causes of spread and measures to be taken were evaluated. Course of population was monitored with pheromone traps placed in 141, 120, and 162 locations in 8 provinces along the coastline of Black Sea Region. High population density was detected at all locations of Artvin and Rize provinces. Since the population interactions continued near the Georgian border, about 98% of the total population in the region was seen in these two provinces. Weekly average population level was 7.36 adults/traps in Artvin and 9.11 adults/traps in Rize Province; spread of the pest continued from east to west and irregular and further-apart local populations were detected at some points. It was determined that it caused population density-dependent economic damage on different hosts including hazelnut, kiwi, citrus, maize and beans. This research examined the H. halys population distribution in Türkiye, potential problems associated to that too, ways that it spreads, and possible solutions.