Using GIS Technology To Protect Gambia’s Territorial Waters

“Gambia, West Africa, is a sliver of a country dwarfed by the enormity of the African continent, like a tiny Band-Aid on the side of an elephant.” That eye-catching sentence opens a colorful GPS World article written by Carlo Cesa and Don Trone. The article is entitled, “A GPS Fish Story: Getting Gambian Waters Under […]
“Gambia, West Africa, is a sliver of a country dwarfed by the enormity of the African continent, like a tiny Band-Aid on the side of an elephant.” That eye-catching sentence opens a colorful GPS World article written by Carlo Cesa and Don Trone. The article is entitled, “A GPS Fish Story: Getting Gambian Waters Under Control.” Gambia is an underdeveloped country, but because it happens to lie along the coast of Africa, its citizens control – under international law – nutrient-rich waters teeming with fish. Unfortunately, large numbers of fishermen swarm in from other countries – Korea, China, Greece, Spain. For years those visiting fishermen have been taking fish illegally from Gambian waters. By some estimates, foreign vessels catch at least half the fish. Consequently, new methods for protecting Gambia’s territorial waters are desperately needed. Video and still cameras working in partnership with inexpensive Navstar receivers and an application-specific GIS database provided a high-technology approach that can be implemented by relatively unskilled technicians. Specially equipped airplanes fly over the fishing waters in random time-varying patterns. Then, whenever the flight crew spots a suspicious-looking vessel, the pilot swoops down as low as 60 feet over the water so the vessel’s tell-tale markings can be imaged with video and still cameras (see Figure 1).
In order to monitor illegal fishing near its shores, the government of Gambia is making use of a Geographic Information System skillfully coupled with an airborne imaging system driven by inexpensive Navstar receivers. Whenever the government agents spot a suspicious-looking vessel plying Gambian waters, they use onboard video and film cameras to record its appearance and its movements across the sea. GPS position coordinates and timing measurements (accurate to a small fraction of a second) are automatically imprinted on each frame of the film, thus making legal prosecution convenient and practical.
Each image is automatically stamped with relevant flight data, GIS database information, and current GPS-derived longitude and latitude positioning coordinates. This real-time information clearly establishes the location of the vessel and any illegal activities of the crew being photographed, thus providing visual proof of clandestine fishing operations. Gambia is an underdeveloped country populated by only about one million citizens. But the relatively simple GIS/GPS technology its technicians have perfected, in cooperation with Western experts, is quickly being duplicated in many other parts of the world. Norway, Germany, Sierra Leone, Senegal, and New Zealand have all implemented vaguely similar monitoring systems to guard their shores against illegal fishing fleets. “Gambia has proved that advanced technology doesn’t have to be complex and expensive,” Carlo Cesa and Don Trone conclude. “Their approach can enable smaller and less economically developed countries to participate in the technology explosions of the more prosperous nations.”