APECS multidisciplinary polar talks I (7 Oct 2021, 15:00)

Dr. Kylie Owen: How do whales find prey? Investigating the use of natural chemical gradients as a foraging tool.

Finding sufficient prey to fuel energy requirements is a challenge for all animals, particularly for baleen whales that have large energy demands due to their size. We use concurrent sampling of chemical gradients (specifically dimethyl sulfide (DMS)), prey biomass, and predator distribution and behaviour to investigate if whales can locate prey using ocean chemistry. Our research focuses on zooplankton specialist species and populations, such as humpback whales feeding on Antarctic krill on the Antarctic Peninsula. Given the role of DMS in global climate regulation, further understanding of the conditions and scales over which these gradients occur, and how they are used by predators, is essential to predicting the impact of future changes in the ocean on predator foraging success.

Affiliation:
Woods Hole Oceanographic Institution, USA
University of Tasmania, Institute for Marine and Antarctic Studies, Australia
Swedish Museum of Natural History, Sweden

Heather L. Selley: Widespread speed up in the Getz region of Antarctica over the last 25 years

Heather will talk about her recent work on dynamic imbalance of the Getz region of West Antarctica. This work combined satellite observations and an ice sheet model to measure the change in ice speed and mass balance of the drainage basin over the last 25-years. years. The results show a mean increase in speed of 23.8 % between 1994 and 2018, with three glaciers accelerating by over 44%. Overall, dynamic imbalance accounts for two thirds of the mass loss from this region of West Antarctica over the past 25-years, with a longer-term response to ocean forcing the likely driving mechanism.

Affiliation:
University of Leeds, Center for Polar Observation and Modelling (CPOM), England