An organism evaluation system for analyzing organisms within a fluid flow, comprising one or more of a stimulation section comprising a means for inducing a motive response in a living organism within the fluid flow passing through the stimulation section and a shepherding section comprising a means for temporarily separating such an organism from and then returning it to the fluid flow, a flow normalizing section in fluid communication with the stimulation section and/or shepherding section, and a viewing section in fluid communication with the flow normalizing section, the viewing section comprising a body having formed therein a body cavity defining a viewing port, the viewing section further comprising an optical system mounted relative to the body for viewing the fluid flow within the viewing port through a cavity first opening, whereby image data relating to the fluid flow and organisms therein is acquired via the optical system for analysis.
