Modeling Diel Vertical Migration Behavior of ZooplanktonDiel vertical migration (DVM) of zooplankton is the daily cycle of movement towards and away from the surface of a lake that results from the need to avoid predation and forage for food. The process of diel vertical migration is one of the main forces creating the spatial and temporal structure of aquatic food webs, often acting as the biological pump that moves carbon around an aquatic environment.
In Daphnia, a genus of crustacean zooplankton, this behavior is triggered in response to both light intensity and chemical signaling by predators. As a result, diel vertical migration changes in intensity in response to fish populations and conditions in the lake that affect light penetration. This measure of how far zooplankton move is known as the migration amplitude. Until this point, predicting a vertical distribution of Daphnia within a given lake has been difficult given the cumbersome nature and unintuitive results of the mathematics involved. Fortunately, with today’s computing power, reasonable estimates as to how Daphnia are vertically distributed within a lake can be calculated based on conditions already monitored by management agencies and research networks. We are developing an R package that can generate an estimated vertical distribution of Daphnia pulex in a lake based on known temperature gradients, light level and attenuation, food availability, and predator abundance. This knowledge can be useful for predicting the vertical position of Daphnia populations in a lake of interest for management purposes but also for making predictions about how Daphnia populations will respond to changing environments with conditions that do not yet exist but likely will in the future. Related Reading:
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