A comparison of predacious aquatic insect fauna and density in ground pools and concrete pools created during the Great East Japan Earthquake in 2011

摘要

The tsunami caused by the Great East Japan Earthquake on March11，2011 hit the Pacific coast and caused heavy destruction of natural and man-made environments in north-eastern Japan. This study focuses on mosquito larvae and their potential aquatic insect predators associated with ground pools and pools that appeared in the concrete foundations of destroyed houses (concrete pool) in inundated areas in Miyagi Prefecture, Japan. Field samplings were conducted on late July 2013. Culex inatomu, Cx. pipiens group, Cx. tritaeniorhynchus, and Cx. orientalis were collected from ground pools and concrete pools. The abundance of Cx. inatomii and Cx. pipiens groups in concrete pools was significantly greater than that in the ground pools. Alarge number of Hydrogfyphus japonicus were collected as potential mosquito preaators, followed by Micronecta spp., Enochrus japonicus, Rhantus sturaliSy Aquariuspaludm paludum ana Hydrochara affinis, categorized as "flight dispersers, which might immigrate rapidly from thenon-inundated rice neids or wetlands. Stepwise generalized linear models suggested that larval abundance of Cx. inatomti in the pools studied was affected by the vegetation cover and habitat type (ground pool or concrete pool), but not by water depth, salinity, presence of predators, and bottom type (sand or concrete) of aquatic bodies. Concrete pools and covered with dense vegetation provide breeding habitat for Cx. inatomii along with their potential predators.