Behavioral Responses of Zooplankton to Thin Layers
نویسنده
چکیده
My approach is to undertake a series of well replicated experiments on a broad range of zooplanktonic taxa, including copepods, larval fish, larval euphausiids, and ciliates. Our experimental apparatus consists of a series of six columnar tanks equipped with infra-red video cameras that continuously scan the full vertical range (210 cm) of each tank and thereby determine the vertical distribution of organisms over a several day period (Fig. 1). Each custom Plexiglas tank is fitted with eight sets of valves (one input and one outflow) spaced at intervals to allow for adding or withdrawing water samples for manipulation or analysis (e.g., nutrients, chlorophyll or ciliates). A natural light simulation system is comprised of a light source and a dusk/dawn simulation wheel made of increasing layers of neutral density blocking gel. The light source for filming is an infrared light-emitting diode (IR-LED). A video camera fitted with a macro/zoom lens is mounted in front of the tank. Zooplankters are seen as silhouettes and recorded on a VCR with a date/time recorder. This entire
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