Data from: Quantifying dispersal of a non-aggressive saprophytic bark beetle

We performed a mark-recapture experiment to examine patterns of adult dispersal in Hylurgus ligniperda (F.) (Coleoptera: Scolytinae), a non-aggressive, saprophytic bark beetle. The experiment took place in a clearcut pine, Pinus radiata D. Don forest in the central North Island, New Zealand, during February to May 2014. Both flight-naïve and flight-experienced H. ligniperda were released in the center of a circular trap grid that extended to 960 m with 170 or 200 panel traps baited with alpha-pinene and ethanol. Of the 18,464 marked H. ligniperda in 12 releases, 9,209 (49.9%) of the released beetles flew, and 96 (1.04%) of the beetles that flew were recaptured. Males and females were recaptured at all distances. The recapture of flight-experienced beetles declined with dispersal distance, and mechanistic diffusion models showed heterogeneous dispersal tendencies within the population. Our best model estimates that 46% (CI95: 19% - 63%) of flight-experienced beetles disperse > 1 km, and 1.6% > 5 km (CI95: 0.02% - 11%). Equal recapture of flight-naive beetles at all distances suggests that emerging H. ligniperda may require a period of flight to initiate chemotropic orientation behavior and subsequent attraction to traps. Quantitative estimation of the distribution of dispersal distances can be used to model the dispersal process of bark beetles and contributes to the management of phytosanitary risks. For instance, combining landscape knowledge of source populations with dispersal processes facilitates estimation of pest pressure at economically sensitive areas such as harvests and timber storage sites. Quantitative dispersal estimates also inform pest risk assessments by predicting spread rates for H. ligniperda that has proven establishment capabilities in other countries.

本研究开展了标记-重捕试验（mark-recapture experiment），以探究非攻击性腐生树皮甲虫——红足材小蠹（Hylurgus ligniperda (F.)，鞘翅目（Coleoptera）小蠹亚科（Scolytinae））的成虫扩散格局。试验于2014年2月至5月在新西兰北岛中部的辐射松（Pinus radiata D. Don）皆伐林内进行。研究人员将未飞行过（flight-naïve）与有飞行经验（flight-experienced）的红足材小蠹释放至圆形诱捕网格的中心，该网格半径延伸至960米，共布设170或200个以α-蒎烯（alpha-pinene）和乙醇（ethanol）为诱芯的板式诱捕器（panel traps）。在12次释放的18464头标记个体中，共有9209头（占释放总数的49.9%）成虫完成飞行，其中96头（占飞行个体的1.04%）被重捕。雌雄成虫在所有诱捕距离下均有重捕记录。有飞行经验个体的重捕率随扩散距离增加而下降，机制扩散模型显示种群内个体间的扩散倾向存在异质性。本研究的最优模型估算结果显示，46%（95%置信区间（CI95）：19%~63%）的有飞行经验成虫扩散距离超过1千米，1.6%（95%置信区间：0.02%~11%）的个体扩散距离超过5千米。未飞行过的成虫在所有距离下重捕率无显著差异，这表明初羽化的红足材小蠹可能需要经历一段飞行过程，才能启动趋化定向（chemotropic orientation）行为并后续被诱捕器吸引。扩散距离分布的定量估算可用于构建小蠹科昆虫的扩散过程模型，有助于植物检疫风险（phytosanitary risks）管理。例如，将源种群的景观分布信息与扩散过程相结合，可辅助估算经济敏感区域（如采伐区与木材存储点）的害虫种群压力。定量扩散估算还可通过预测红足材小蠹的扩散速率，为害虫风险评估提供依据——该虫已在多个国家被证实具备定殖能力。