USAP-DC

Overview: This project has two goals. The first is to investigate the responses of Antarctic krill Euphasia superba to flow and chemical stimuli indicating food and predation risk, the interaction of these cues, and how krill responses to these cues depend on the photic environment. This project will will determine threshold responses, the ability of krill to orient to horizontal and vertical flows, whether chemical cues polarize responses to flow and whether this differs with attractive vs. aversive cues, and how these responses are affected by light intensity. This will determine how and under what specific conditions the flow, chemical and light environment can either attract or repel krill, and whether krill can use flows to transport themselves towards beneficial environments and away from risky ones. The second goal is to examine whether the behavioral responses of individual krill can be scaled up to predict the properties of aggregations such as density, coherence, swimming speed and direction. This project will use a modeling approach to determine properties of krill aggregations in defined oceanographic conditions characteristic of the southern ocean to examine links between individual behavior and aggregation properties in physically realistic scenarios. Intellectual Merit: Krill are an ecologically important component of all high latitude food webs and constitute a growing fishery yet we know very little about their behavior in response to environmentally relevant chemical, flow and photic conditions. Understanding krill demography can be enabled by examining individual responses to light, attractive (food related) and aversive (predator related) chemical cues, flow, light and their interactions. This analysis can be used to define/predict preferred environments, define the capacity of krill to detect and move to them (and away from unfavorable ones), better parameterize models of DVM, and krill energetics. Linking individual behavior to aggregations will improve our ability to use passive acoustic sampling of krill to understand their biology by providing insight into what krill are doing in aggregations that display particular features, and help define useful properties to characterize aggregations. The role of biology vs. physical forcing in determining zooplankton distributions, and the relationship between individual behavior and emergent group properties are fundamental questions. Broader Impacts: Antarctic krill (Eupahusia superba) are dominant members of the Southern Ocean. They are a critical resource for higher predators, are considered an ecosystem engineer, are the most highly linked species in Antarctic food webs, exert top down control on phytoplankton abundance and represent the largest Antarctic fishery. This project will therefore impact our understanding of the ecology of high latitude systems, their capacity to respond to environmental perturbations (like climate change), and krill fisheries management. Project PIs will engage conservation and management experts to vet and use the developed software tools, as well as to share results. The project will support one post-doctoral associate to be trained in a highly interdisciplinary environment, and provide graduate and undergraduate research opportunities in ocean sciences, biology and engineering. Products will include open source code for behavioral modeling, K12 curricular materials based on these models as well as digital archives of krill behavior, and a variety of public engagement activities.

Person	Role
Fields, David	Investigator and contact
Record, Nicholas	Co-Investigator

Antarctic Organisms and Ecosystems	Award # 1840949
Antarctic Integrated System Science	Award # 1840941
Antarctic Organisms and Ecosystems	Award # 1840941
Antarctic Organisms and Ecosystems	Award # 1840927

USAP-1840949_1

None in the Database

1. Garayev, K., & Murphy, D. W. (2021). Metachronal Swimming of Mantis Shrimp: Kinematics and Interpleopod Vortex Interactions. Integrative and Comparative Biology. (doi:10.1093/icb/icab052)