Lantschner M Victoria, Corley Juan C, Liebhold Andrew M
Grupo de Ecología de Poblaciones de Insectos, Instituto de Investigaciones Forestales y Agropecuarias Bariloche (IFAB), INTA - CONICET, Modesta Victoria 4450, Bariloche, Argentina.
Departamento de Ecología, CRUB Universidad Nacional del Comahue, Quintral 1250, Bariloche, Argentina.
Ecol Appl. 2020 Jul;30(5):e02103. doi: 10.1002/eap.2103. Epub 2020 Mar 26.
Biological invasions are affected by characteristics of invading species, strength of pathway connectivity among world regions and habitat characteristics of invaded regions. These factors may interact in complex ways to drive geographical variation in numbers of invasions among world regions. Understanding the role of these drivers provides information that is crucial to the development of effective biosecurity policies. Here we assemble for the first time a global database of historical invasions of Scolytinae species and explore factors explaining geographical variation in numbers of species invading different regions. This insect group includes several pest species with massive economic and ecological impacts and these beetles are known to be accidentally moved with wood packaging in global trade. Candidate explanatory characteristics included in this analysis are cumulative trade among world regions, size of source species pools, forest area, and climatic similarity of the invaded region with source regions. Species capable of sib-mating comprised the highest proportion on nonnative Scolytines, and these species colonized a higher number of regions than outbreeders. The size of source species pools offered little power in explaining variation in numbers of invasions among world regions nor did climate or forest area. In contrast, cumulative trade had a strong and consistent positive relationship with numbers of Scolytinae species moving from one region to another, and this effect was highest for bark beetles, followed by ambrosia beetles, and was low for seed and twig feeders. We conclude that global variation in Scolytine invasions is primarily driven by variation in trade levels among world regions. Results stress the importance of global trade as the primary driver of historical Scolytinae invasions and we anticipate other hitchhiking species would exhibit similar patterns. One implication of these results is that invasions between certain world regions may be historically low because of past low levels of trade but future economic shifts could result in large numbers of new invasions as a result of increased trade among previously isolated portions of the world. With changing global flow of goods among world regions, it is crucial that biosecurity efforts keep pace to minimize future invasions and their impacts.
生物入侵受到入侵物种的特性、世界各地区之间途径连通性的强度以及被入侵地区的栖息地特征的影响。这些因素可能以复杂的方式相互作用，从而导致世界各地区入侵数量的地理差异。了解这些驱动因素的作用，可为制定有效的生物安全政策提供至关重要的信息。在此，我们首次汇编了一个关于小蠹亚科物种历史入侵的全球数据库，并探讨解释不同地区入侵物种数量地理差异的因素。这个昆虫类群包括几种具有巨大经济和生态影响的害虫物种，并且已知这些甲虫会在全球贸易中随木质包装意外传播。该分析中纳入的候选解释特征包括世界各地区之间的累计贸易、源物种库的大小、森林面积以及被入侵地区与源地区的气候相似性。能够近亲交配的物种在非本地小蠹亚科中所占比例最高，并且这些物种比杂交繁殖的物种在更多地区定殖。源物种库的大小在解释世界各地区入侵数量的差异方面作用不大，气候或森林面积也是如此。相比之下，累计贸易与从小蠹亚科一个地区转移到另一个地区的物种数量之间存在强烈且一致的正相关关系，并且这种效应对于树皮甲虫最高，其次是食菌小蠹，对于种子和嫩枝取食者则较低。我们得出结论，小蠹亚科入侵的全球差异主要由世界各地区贸易水平的差异驱动。结果强调了全球贸易作为历史上小蠹亚科入侵的主要驱动因素的重要性，并且我们预计其他搭便车物种也会呈现类似模式。这些结果的一个含义是，由于过去贸易水平较低，某些世界地区之间的入侵在历史上可能较少，但未来的经济转变可能会因世界先前孤立地区之间贸易增加而导致大量新的入侵。随着世界各地区之间全球货物流动的变化，生物安全措施必须跟上步伐，以尽量减少未来的入侵及其影响，这一点至关重要。
