Seeing stripes: Professors create GPS zebra tracker

Princeton engineers and evolutionary biologists are hard at work creating new technology that will track the smallest movements and interactions of - zebras?

The Engineering School and the EEB department have collaborated to create a biological tracking device named ZebraNet that may well change the face of zoology.

ZebraNet is a system in which zebras are fitted with collars containing a GPS chip, flash memory and a radio transceiver that can broadcast information from multiple zebras to scientists at a base station. "What makes this technology unique is its ability to transmit information from other zebras broadcasting to it," explained biology Professor Dan Rubenstein, who is heading the project from the EEB department. "This type of redundancy in recovering data from many animals . . . will make it possible to study the individual movement dynamics of many wildlife species at a fine-grained level."

Sensors on the collars will record any movement made by the animal. Microphones will record verbal communication, and miniature cameras will record time-lapse images of the landscapes through which the zebras move.

ZebraNet will allow scientists to explore the habits and communal behavior of zebras in a way never before possible. The GPS system can track the movements of the animals over far greater ranges than older technologies allow.

The radios that have been used to track animals until now can only function within a certain radius of a base station. But the new GPS system transmits each creature's location to a satellite, which relays the information back to scientists, allowing the zebras to roam where they please.

EEB major Mindy Rostal '03 - who is doing her thesis work on the competition between zebras and cattle - said she thinks ZebraNet will open new doors in the field of animal behavior.

"This research is not just going to apply to zebras, but to all animals," Rostal said enthusiastically. "All you need to do is locate one collared animal and it will give you information about all the other animals it has come into contact with since the last time you downloaded. Not only will you be able to record accurate information about the movements of a single animal, but about its interactions with other species and with other animals of its own species, i.e. how often two harems join to make a herd."

Rubenstein hopes the technology will take off, and that similar devices will soon be used on mammals of all sizes and habitats, from small species such as baboons to giants such as elephants.

The idea for ZebraNet originated when Rubenstein and engineering professor Margaret Martonosi found a connection between zebras and campus tours. Rubenstein needed a real-time system to track the movements of animals while Martonosi had recently invented a GPS palm pilot campus tour system that guides its carrier from one campus building to another interactively.

Scientists hope to complete preliminary tests on human cyclists before winter break. After experimenting with the technology on livestock at a nearby stable, the group will take its tools to Kenya, testing them on zebras at the Impala Research Center directed by the University, the Smithsonian Institute, and the Kenya Wildlife Service and National Museum.