Marine mammals exhibit extreme physiological and behavioral adaptions that allow them to dive hundreds to thousands of meters underwater despite their need to breathe air at the surface. Through the development of new remote monitoring technologies, we are just beginning to understand the mechanisms by which they are able to execute these extreme behaviors. Long- term animal-borne tags can now record location, dive depth, and dive duration and then transmit these data to satellite receivers, enabling remote access to behavior occurring both many kilometers out to sea and several kilometers below the ocean surface.
Graduate Students: Jillian Wisse, University Program in Ecology; Vivienne Foroughirad, Marine Science & Conservation
Faculty: Dr. Andrew Read
Course: Biology of Marine Animals, Biology 376A, ENVIRON 376A & Environ 776A
This dataset includes 30 satellite-linked tags deployed by Duke Marine Lab researchers between 2014 and 2017 as part of the US Navy Marine Species Monitoring Program. Students used these data to explore comparative diving behavior between two deep-diving species off the North Carolina coast, short-finned pilot whales (Globicephala macrorhynchus) and Cuvier’s beaked whale (Ziphius cavirostris). Beaked whales are the deepest divers of all mammals, with recorded dives of almost 3000 meters, and are especially enigmatic, spending up to 95% of their time below the ocean surface.
Exercises
- Pre-process satellite tag data to remove corrupted records and identify gaps.
- Plot dive profiles for individual pilot whales and beaked whales.
- Calculate summary statistics for dive depths and durations.
- Compare plots of dive distributions for each species.
Techniques
- R & RStudio – Import data from excel and csv files
- Parse data and properly format data types
- Visualize dive data in dive profile plots
- Calculate summary statistics
- Plot line graphs and scatterplots
