Document Type

Honors Project

Publication Date

6-5-2024

Abstract

Many species of zooplankton exhibit the predator avoidance behavior called diel vertical migration (DVM). During typical DVM, zooplankton ascend to surface waters during the night and descend to deeper water during the day where predation by visual predators is reduced due to lower light levels (Goldman and Horne 1983; Wetzel 1983). DVM is highly variable and the degree to which it is induced can fluctuate based on factors such as zooplankton size, changes in light intensity, and predator chemical cues (Van Gool and Ringelberg 1995, cited in Weber and Noordwijk 2002). Although DVM has been well studied using the genus Daphnia at the population level, swimming behavior at the subpopulation level has received little attention and may conflict with or expand on current understandings of typical DVM behavior (Dodson et al. 1995; Nesbitt et al. 1996). This study used a customizable 2D video analysis system to (i) characterize small-scale swimming behavior of Daphnia magna under different DVM-inducing stimuli (light intensity, predator chemical cues, stage of development/size), and (ii) determine the importance of multiple stimuli on driving DVM. Two size classes (i.e., juvenile and adult) of D. magna were reared and exposed to aged tap water (i.e., control), fish kairomone water (i.e., Lepomis sp.), or invertebrate kairomone water (i.e., Chaoborus punctipennis) and placed in a filming chamber. Videos were analyzed for vertical distribution, swimming velocity, and distance traveled by D. magna using the manual tracking feature in ImageJ. Results indicated that D. magna respond to multiple stimuli in their environment and can adjust DVM behavior accordingly to reduce predation risk.

Level of Honors

summa cum laude

Department

Biology

Advisor

Bart De Stasio

Download

Included in

Biology Commons

Share

COinS