DARWIN is a computer vision system that helps researchers to identify individual bottlenose dolphins, Tursiops truncatus, facilitating the comparison of digital images of the dorsal fins of new dolphins with a database of previously identified dolphin fins. In addition to the digital dorsal fin image and an approximation of the fin outline, textual information containing sighting data is stored for each of the previously identified dolphins. The software uses a semi-automated process to create an approximation of the fin outline. The outline is used to formulate a sketch based query of the dolphin database. The system utilizes a variety of image processing and computer vision algorithms to perform the matching process which is necessary to identify those previously identified fins which most closely resemble the unknown fin. The program presents the database fin images to the researcher in rank order for comparison with the new fin image.