Mercer David R, Washburn Jan O, Anderson John R
Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA 94720, USA.
J Vector Ecol. 2010 Jun;35(1):20-7. doi: 10.1111/j.1948-7134.2010.00023.x.
Vertical stratification of treeholes used by mosquitoes may reflect resource quality or result from interspecific competition. Mosquitoes able to monopolize treeholes with optimal resources may be over-represented in the community. Aedes sierrensis, which is well adapted for the Mediterranean climate of California, has evolved in the absence of interspecific competition, so oviposition should reflect resource quality to a large extent. Artificial oviposition traps mounted at four canopy heights facing north or south on trees in a mixed-oak forest at four elevations of the Pacific Coastal Range were used to assess vertical ovipositional preferences by the western treehole mosquito. Natural dispersal of the ciliated protozoan parasite Lambornella clarki was similarly monitored. Gravid Ae. sierrensis showed no vertical stratification during egg laying in traps. Lambornella clarki were naturally dispersed at relatively low frequency into traps and persisted unless eliminated by larval predation. Aedes sierrensis is not currently constrained into occupying a subset of treeholes. However, invasion of its native range by competitive species may alter oviposition patterns.
蚊子使用的树洞垂直分层可能反映资源质量，也可能是种间竞争的结果。能够独占具有最佳资源树洞的蚊子在群落中可能占比过高。适应加利福尼亚地中海气候的塞拉伊蚊在没有种间竞争的情况下进化而来，因此产卵在很大程度上应反映资源质量。在太平洋沿岸山脉四个海拔高度的混交栎林中，在面向北或南的四个树冠高度安装人工产卵诱捕器，以评估西部树洞蚊的垂直产卵偏好。同样监测了纤毛原生动物寄生虫克拉克兰氏虫的自然传播情况。怀卵的塞拉伊蚊在诱捕器中产卵时没有表现出垂直分层。克拉克兰氏虫自然传播到诱捕器中的频率相对较低，并且会持续存在，除非被幼虫捕食消除。目前，塞拉伊蚊没有被限制在特定的树洞子集内。然而，竞争物种对其原生范围的入侵可能会改变产卵模式。
