Bradshaw Milliam E, Holzapfel Christina M
Department of Biology, University of Oregon, 97403, Eugene, OR, USA.
Oecologia. 1992 May;90(2):227-237. doi: 10.1007/BF00317180.
The insect fauna of water-filled tree holes in southern Britain consists primarily of the mosquitoes Aedes geniculatus, Anopheles plumbeus, Culex torrentium, and a benthic detritivorous fauna that includes primarily the scirtid beetle Prionocyphon serricornis and the chironomid midge Metriocnemus martinii. Culex torrentium has been documented only relatively recently in tree holes but all three species of mosquitoes partition the resource in space and time. When mosquito larvae were forced to coexist in natural tree holes at limiting densities and at higher than natural levels of interspecific encounter, there was no evidence that Aedes geniculatus or Anopheles plumbeus affected pupation success, pupal weight, or development time of the other or that either Aedes geniculatus or C. torrentium affected the survivorship, pupation success, pupal weight, and biomass yield of the other. When A. geniculatus at limiting densities were forced in natural tree holes to live without or to coexist with natural or twice natural densities of P. serricornis and M. martinii, the presence, absence, or superabundance of the benthic insects did not affect pupation success or pupal weight of A. geniculatus; development time of A. geniculatus was faster when a superabundance of the benthic fauna was present. Effects of the benthic fauna on A. geniculatus are slight and the only significant interaction is facilitative, not competitive. The pattern of habitat segregation among treehole mosquitoes in southern Britain is characteristic of their respective genera and we propose that this pattern is more likely (but not certain) to have arisen through a process of independent evolution than through competitively driven niche shifts among already coexisting species.
英国南部充满水的树洞中的昆虫群落主要由蚊科的膝斑伊蚊、铅色按蚊、溪流库蚊，以及底栖食碎屑动物群落组成，该群落主要包括锯角伪吉丁甲和马丁摇蚊。溪流库蚊直到最近才在树洞中被记录下来，但这三种蚊子在空间和时间上对资源进行了分配。当蚊幼虫被迫在自然树洞中以有限的密度共存，且种间相遇水平高于自然水平时，没有证据表明膝斑伊蚊或铅色按蚊会影响对方的化蛹成功率、蛹重或发育时间，也没有证据表明膝斑伊蚊或溪流库蚊会影响对方的存活率、化蛹成功率、蛹重和生物量产量。当自然树洞中密度有限的膝斑伊蚊被迫与自然密度或两倍自然密度的锯角伪吉丁甲和马丁摇蚊共存或不共存时，底栖昆虫的存在、缺失或过剩并不影响膝斑伊蚊的化蛹成功率或蛹重；当底栖动物过剩时，膝斑伊蚊的发育时间会更快。底栖动物群落对膝斑伊蚊的影响很小，唯一显著的相互作用是促进作用，而非竞争作用。英国南部树洞蚊子的栖息地隔离模式是其各自属的特征，我们认为这种模式更有可能（但不确定）是通过独立进化过程形成的，而不是通过已经共存的物种之间竞争性驱动的生态位转移形成的。
