Shark spotting fits a pattern

Pattern-recognition software developed by astrophysicists to locate stars and galaxies could help save the whale shark, Rhincodon typus, from extinction. In the British Ecological Society Journal of Applied Ecology, Australian marine biologist Brad Norman, JAVA programmer Jason Holmberg, and astrophysicist Zaven Arzoumanian of the Universities Space Research Association (Columbia, MD, USA; www.usra.edu) write that the Groth algorithm--developed by astronomers for the comparison of two lists of coordinates such as the x, y positions of stars--could be adapted to identify individual whale sharks.

Says Arzoumanian, "The contrast of white whale shark spots on darker skin is well suited to blob extraction. The spatial relationships between these groups form the basis for a unique identifier for each shark." The full potential of photographic identification of whale sharks has rarely been exploited because of the unmanageable task of making visual identification in large data sets. The authors have set up the ECOCEAN Whale Shark photo-identification library to act as a repository for whale-shark photographs taken by divers and tourists, as well as researchers.