Objective This study aimed to clarify the occurrence patterns and damage dynamics of Ips hauseri in the Hami forest region, Xinjiang of northwestern China and to provide a scientific basis for monitoring and control.

Method From 2024 to 2025, field investigations were conducted in natural Picea schrenkiana forests in the Hami region. A combination of plot surveys, pheromone trapping and bark-peeling surveys was used to investigate the flight activity patterns and life history of I. hauseri adults, and to compare the distribution of adults on the trunks of spruce trees with different damage types. In addition, the health condition of spruce trees within the plots was recorded, and frequency distribution fitting and aggregation indices were applied to analyze the spatial distribution patterns of damaged spruce trees in plots with different infestation levels.

Result (1) Under natural conditions in the Hami forest region, I. hauseri completed one generation per year. Overwintered adults began to emerge from the soil and become active in late April, while newly emerged adults entered the soil for overwintering from mid-August to early September. (2) Adult flight activity occurred from May to September. The flight period of overwintered adults extended from May to June, peaking around June 10, whereas that of newly emerged adults lasted from July to September, with a peak around July 16. Marked differences were observed in daily flight rhythms among different periods: a single-peak pattern was recorded in late May, while a double-peak pattern occurred in late July. (3) Adults on damaged spruce trees were mainly distributed in the middle sections of trunk, with lower densities in the upper and lower sections. (4) Analysis based on frequency distribution fitting and aggregation indices showed that, with increasing damage severity, the spatial distribution of damaged spruce trees shifted from a highly aggregated pattern to a weakly aggregated pattern, and eventually approached a random distribution.

Conclusion This paper clarifies the flight activity patterns and life history of adult I. hauseri in the Hami forest region of Xinjiang, and reveals the distribution patterns of adults on spruce trunks with different damage types, as well as the spatial pattern changes of damaged spruce trees in plots with different infestation levels.