WHALE TRACKING RESEARCH

The sperm whale is one of the deepest diving whales, descending up to two miles below sea level. As this species may be the largest toothed predator to live on Earth, the deep-water feeding behavior of sperm whales has been of great interest to scientists. Due to the logistics of following a sperm whale to its feeding depths, however, whale researchers have long been unable to examine these animals' underwater behavior. Until recently, scientists could only observe sperm whales at the surface or during shallow dives in clear water.

Iain Kerr has utilized a process to track sperm whales using a multi-beam scanning sonar. This technique enables researchers to calculate the whale's rate of descent, ascent, maximum depth, bearing, and speed throughout complete dives. This information enables institute researchers to create a three-dimensional diagram of the whale's dive. Using this technology the Century crew began a fifteen month study of sperm whale diving and feeding behavior on the whales' breeding grounds near the Galapagos Islands.

Alliance research on sperm whale behavior has also included acoustic research, satellite tracking, and collection and analysis of sperm whale skin and fecal samples. Hydrophones are used to record the echolocations and vocalizations of the whales while deploying a deep-water probe in areas of whale activity to record temperature, oxygen and salinity levels. Researchers combine hydrophone and probe data with the dive diagrams to investigate correlations among diving and sounding behavior and environmental conditions.

To monitor whale movement, Institute researchers assisted Dr Bruce Mate (a professor of Fisheries and Wildlife and Oceanography at Oregon State University) in attempting to attach satellite-linked radio tags to three sperm whales. Two of the tags registered location, water temperature and depth; the third registered location only.

Century personnel took photo-identification shots of individual whales. These photo IDs are used for comparison studies and will eventually be contributed to identification catalogues for each species. The Ocean Alliance created the main southern right whale catalogue of photo-identification shots. This information is available to other researchers. An Equadorian marine biologist will be using this identification data to support an ongoing whale census in the Galapagos Islands region.