Dispersal and Spatiotemporal Dynamics of Asian Longhorned Beetle (Coleoptera: Cerambycidae) in China

We studied dispersal and spatiotemporal dynamics of the Asian longhorned beetle, Anoplophora glabripennis Motschulsky, in Gansu Province of north central China. We used mass mark–recapture methods and observed that 98% of beetles were recaptured within 920 m from a release point, whereas the median dispersal rate for all recaptured adults was 30 m/d. Dispersal potential within the course of a season for males and gravid females was 2,394 and 2,644 m, respectively; however, more work is needed to evaluate the potential of long-distance dispersal events to initiate new colonies outside current U.S. quarantine boundary guidelines. We observed that tree size and number of existing emergence holes on a tree were significant positive predictors of new emergence holes, but we did not measure a significant effect of tree size, number of existing emergence holes, and number of new emergence holes on adult beetle abundance. Implications of these findings within the context of host quality are discussed, but more research is needed to identify key factors in the multiyear host colonization process. Peak population abundance of unmarked beetles (i.e., background populations) in both 1999 and 2000 occurred between 800 and 900 degree-days (base threshold = 10°C) from 1 January. Background populations exhibited local spatial autocorrelation during peak abundance, with ranges of spatial dependence of 229–543 m. The implications of this study are discussed in reference to the role that A. glabripennis population biology plays in the current eradication effort.