Artim J M, Sikkel P C
Department of Biological Sciences and Environmental Sciences Program, Arkansas State University, State University, AR 72467, USA.
Department of Biological Sciences and Environmental Sciences Program, Arkansas State University, State University, AR 72467, USA; Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom 2520, South Africa.
Int J Parasitol Parasites Wildl. 2016 May 24;5(2):145-57. doi: 10.1016/j.ijppaw.2016.05.003. eCollection 2016 Aug.
Characterizing spatio-temporal variation in the density of organisms in a community is a crucial part of ecological study. However, doing so for small, motile, cryptic species presents multiple challenges, especially where multiple life history stages are involved. Gnathiid isopods are ecologically important marine ectoparasites, micropredators that live in substrate for most of their lives, emerging only once during each juvenile stage to feed on fish blood. Many gnathiid species are nocturnal and most have distinct substrate preferences. Studies of gnathiid use of habitat, exploitation of hosts, and population dynamics have used various trap designs to estimate rates of gnathiid emergence, study sensory ecology, and identify host susceptibility. In the studies reported here, we compare and contrast the performance of emergence, fish-baited and light trap designs, outline the key features of these traps, and determine some life cycle parameters derived from trap counts for the Eastern Caribbean coral-reef gnathiid, Gnathia marleyi. We also used counts from large emergence traps and light traps to estimate additional life cycle parameters, emergence rates, and total gnathiid density on substrate, and to calibrate the light trap design to provide estimates of rate of emergence and total gnathiid density in habitat not amenable to emergence trap deployment.
描述群落中生物密度的时空变化是生态学研究的关键部分。然而，对于小型、活动的、隐匿的物种而言，这样做存在多重挑战，尤其是涉及多个生活史阶段时。食骨等足类动物是具有重要生态意义的海洋外寄生生物，即微型捕食者，它们一生中大部分时间生活在基质中，仅在每个幼体阶段出现一次以吸食鱼血。许多食骨等足类物种是夜行性的，并且大多数具有明显的基质偏好。关于食骨等足类动物对栖息地的利用、对宿主的捕食以及种群动态的研究，已经使用了各种诱捕设计来估计食骨等足类动物的出现率、研究感官生态学以及确定宿主易感性。在本文所报道的研究中，我们比较并对比了出现诱捕、鱼诱捕和灯光诱捕设计的性能，概述了这些诱捕器的关键特征，并确定了从东加勒比珊瑚礁食骨等足类动物马氏食骨等足类（Gnathia marleyi）的诱捕计数中得出的一些生命周期参数。我们还使用大型出现诱捕器和灯光诱捕器的计数来估计其他生命周期参数、出现率以及基质上食骨等足类动物的总密度，并校准灯光诱捕设计，以提供在不适于部署出现诱捕器的栖息地中食骨等足类动物的出现率和总密度的估计值。
