Researchers tag great white sharks after capturing them on the ocean with a GPS-enabled wet-dry tracker. The tracker signals its location to a satellite whenever the shark surfaces during its movements.
During an expedition, a smaller boat baits sharks and pulls them onto the lowered lift that is attached to a bigger boat. The lift raises the shark out of the water and a small team of researchers places a towel over the shark's eyes and puts a tube with fresh running seawater into the shark's mouth. The tube pushes water through the shark's gills so it doesn't suffocate.
The researchers have 15 minutes to take samples, including blood and tissue samples. During the sample taking, trackers are attached to the shark's dorsal fin with strong bolts. The initial placement of the tracker may cause some discomfort, but it doesn't interfere with the shark's movements.
The lift is lowered and the shark is allowed to go free. The GPS tracker is active only when the shark surfaces, but it does provide on-going information about the shark's territory and migration patterns. The tracker must be out of the water for at least 90 seconds and must ping the satellite at least three times to give an accurate GPS location.