Helder, M. 2006.
CS Dialogue 33(1):4-5. CELD ID 19982 Abstract Since the advent of global positioning satellites, or at least since their availability for civilians, scientists have found many uses for these devices. One of the more interesting applications is to track animals such as 'fish with chips' program. This is a multimillion dollar Census of Marine Life project. In conjunction with this program, thousands of marine animals in the Pacific Ocean, including many fish, have been fitted with electronic surveillance tags. As of 2006, midpoint in a ten year program, some interesting results have been recorded. Thus far about 1800 sharks, tuna and turtles have been fitted with transmitting devices which relay information to a satellite when the animal surfaces. By this means, a bluefin tuna was tracked as it crossed the Pacific Ocean three times in 600 days. This fish swam 40,000 km with an average of 66 km/day. More dramatic still were the exploits of Nicole, a 3.5m long great white shark. This specimen swam 11,000 km from South Africa to Australia and back within three months. Nicole thus averaged 122 km/day. She swam in a straight line, never less than 5km/hr and 60% of the time she stayed within one metre of the surface. It is obvious she knew where she was going.
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