February 24, 2010

Strange BiologyUsing Geographic Profiling to Track Great White Shark Predation

Scientists are now using geographic profiling to track great white sharks as they hunt off the coast of South Africa. (Photo credit: Arco Images GmbH/Alamy)

Geographic profiling is a method typically used by criminal investigators to track the movements of serial killers by tracing a connection between crime scenes. Researchers from the University of Miami, University of British Columbia, and Texas State University recently used this method to study the hunting habits of the great white shark off the coast of South Africa.

This research study was the first time geographic profiling was used in a marine environment. Previously, in addition to its use in crime investigations, this technique has been used to study the foraging habits of bats and bees and explore the spread of infectious diseases in Africa.

The hunting tactics of the great white sharks are difficult to observe under natural conditions, so up to now, not much was known about the sharks’ hunting behaviors. In their study, the scientists tracked the movements of great white sharks as they hunted Cape Fur seals at Seal Island in False Bay, South Africa.

Using geographic profiling, the scientists collected data on 340 natural predatory great white shark attacks on seals. In tracking the sharks’ movements, the scientists discovered that the sharks utilize a clearly-defined search base. The researchers found that the search base was not located where the chance of running into seals was the highest. Instead, it was based on a balance between three factors: prey detection, capture rate, and inter-shark competition.

Larger sharks are more successful in capturing seals than smaller sharks. (Photo credit: Corbis)

The researchers determined that the spatial patterns of the sharks did not occur randomly. They also found that larger sharks were more successful in capturing their seal prey than smaller sharks. Smaller sharks in turn had a more dispersed search pattern and a lower kill rate than larger sharks. The scientists think one explanation for this occurrence may be that sharks perfect their search technique over time and must learn to center their hunting efforts in areas where hunting success is more likely. A second explanation proposed by the scientists is that larger sharks exclude the smaller sharks from their hunting areas.

The results of the scientists’ research were published in the Journal of Zoology. Scientists who contributed to this research include R. Aidan Martin of the University of British Columbia, Kim Rosso of Texas State University-San Marcos, and Neil Hammerschlag of the University of Miami.

More to Explore

• Hunting patterns and geographic profiling of white shark predation [abstract]
• Geographic profiling applied to track hunting patterns of white sharks in South Africa
• The Texas State University Center for Geospatial Intelligence and Investigation (GII)
• South Florida Student Shark Program (SFSSP)

Last updated February 24, 2010 | Comments (1) | Permalink | Strange Biology