Emperor penguins are the largest species of marine bird, and perhaps because of their size, they fast longer, dive deeper, and endure harsher conditions than any other avian species. As a top predator in the Antarctic ecosystem, they have a significant top-down effect on prey targeted during long, deep breath-hold dives. It is therefore essential to understand emperor penguin habitat use, diving capabilities, food habits, and behavioral flexibility in order to interpret their role in the food web and their ability to adapt to environmental change. However, studying marine vertebrates has its challenges, as we cannot visually observe their underwater behavior.
During late chick-rearing emperor penguins, a colonial breeding seabird, alternate 5-20+ day foraging trips with short visits to the colony to feed their chicks. During these foraging trips they may travel over 100 kms from the colony and dive to depths exceeding 500 meters for over 30 minutes(Kooyman et al. 1992; Wienecke et al. 2007; K. Sato et al. 2011; Goetz et al. 2018)! Incredible!!
Although researchers may not be able follow penguins on their extreme journeys, engineered data-logging tools (tags) allow us to track animals at fine-scale resolutions. This season we are deploying tags on 20 adult emperor penguins as they head to sea to forage. Four tag types of variable configurations will be used to study at-sea behavior. Some of the data these tags collect include dive depth, acceleration, GPS location, and video allowing us to determine where they go, when they are foraging, and what they are eating. Additionally, the tags collect data telling us about the environment the penguins are using such as temperature and light level. With these data loggers we hope to document many firsts. This will be the first study to document the foraging behavior of penguins from Cape Crozier, one of the southernmost colonies. Additionally, we are excited to visually document the foraging behavior of emperor penguins for the first time using a miniature video-logger developed by Little Leonardo Corporation in Tokyo. We will learn more about what they are eating and how they are catching their prey.
To further our understanding of the hidden lives of emperor penguins we must go where few have gone before.
Dive On,
Emperor Penguin Field Crew
