Seasonal dynamics of the brown marmorated stink bug ( <i>Halyomorpha halys</i> [Stål]) in an urban landscape

During the 2021–2023 period, we investigated the seasonal dynamics of the brown marmoratedstink bug (Halyomorpha halys) at two locations in an urban environment in central Slovenia. Wehave deployed three funnel traps, in combination with aggregation pheromone at each of thelocations. We have recorded daily precipitation and average temperature. The pest wasmonitored at three different developmental stages, i.e. adults, young nymphs and old nymphs.Based on the average daily temperature, we have calculated degree day values (DD). We foundthat, accounting for the lower developmental threshold of 12.2°C, overwintered adults canappear in intervals, when DD reaches already 1°C till 11°C. Young nymphs appear when the DDvalue ranges from 290 to 516°C. Old larvae appear at DD values from 290 to 812°C, and adultsof the first generation are observed when the DD value ranges from 809 to 1054°C. Our resultsrevealed that brown marmorated stink bugs have one generation per year in Central Slovenia,and they are present in the landscape from April to the beginning of November. The results ofour research are among the first in the field of seasonal dynamics of the brown marmoratedstink bug in an urban environment.