Studying the Impacts of Local Oceanographic Processes on Adélie Penguin Foraging Ecology

Abstract

AbstractWe are conducting a multi-platform field study to investigate the impact of local physical processes on Adélie penguin foraging ecology in the vicinity of Palmer Deep off Anvers Island, Western Antarctic Peninsula (WAP). Guided by real-time remotely sensed surface current measurements of convergence derived from a network of high-frequency radars (HFRs), we adaptively sample the distribution and biomass of phytoplankton and Antarctic krill, which influence Adélie penguin foraging ecology, to understand how local oceanographic processes structure the ecosystem. The recent application of ocean observing and animal telemetry technology over Palmer Deep has led to new understanding and many new questions related to polar ecosystem processes. The HFR coastal surface current mapping network is uniquely equipped to resolve local circulation patterns over Palmer Deep. The surface current measurements enable identification of regions of convergence and divergence in real time. Guided by these maps, our field study adaptively samples the measured convergence and divergence zones within the context of semi-diurnal and diurnal mixed tidal regimes. The in situ sampling includes (a) a mooring deployment, (b) multiple underwater glider deployments, (c) small boat acoustic surveys of Antarctic krill, and (d) penguin ARGOS-linked satellite telemetry and temperature-depth recorders (TDRs). The combination of real-time surface convergence maps with adaptive in situ sampling introduces HFR to the Antarctic in a way that allows us to rigorously and efficiently test the influence of local tidal processes on top predator foraging ecology.