Scientists follow bull sharks with satellite tags, and each study measured something different. In the study off northeastern Brazil, the one bull shark that was tagged off Recife in 2012 was a mature male, 210 centimetres long, and it covered more than 3,000 kilometres in 75 days. A tagging study off northeastern Brazil also found three residency periods, which means times when the sharks stayed in one area, and these lasted at least 5 to 17 days. A different satellite-tag study, from 2005 to 2007, tagged 18 bull sharks with a mean size of 164 centimetres fork length. Their tags stayed on for up to 85 days, with a median of 30 days, and the tagged sharks stayed mostly between 26 and 33 degrees Celsius.

Several reports describe how far and how fast bull sharks travel, but the numbers are not the same kind of measurement. In the 2005 to 2007 tag study, bull sharks generally travelled 5 to 6 kilometres a day, and an average of 143.6 kilometres in all. Another report says bull sharks have been recorded covering up to 180 kilometres in 24 hours, which is the most that was seen in a single day. Over short distances, bull sharks have been recorded swimming at about 19 kilometres an hour. A bull shark often swims slowly near the bottom until prey appears, and in the western Atlantic, bull sharks travel north along the coast of the United States in summer.

Trackers also show where in the water bull sharks spend their time. In a satellite-tag study, bull sharks spent most of their time in water shallower than 20 metres. A fish database says bull sharks are usually found at depths of 1 to 30 metres, and it gives their whole depth range as 1 to 164 metres. Bull sharks are usually found in water less than 30 metres deep. In one tracking study, bull sharks in an estuary swam closer to the surface at night and stayed in deeper water during the day, while in another tracking study, young bull sharks in an estuarine river system moved upstream during the day and downstream at night.

The tags and trackers fit what is known about where bull sharks live around the world. In the western Atlantic they have been found from Massachusetts to southern Brazil, and in the Indo-West Pacific they have been found from Kenya and South Africa to India, and from Vietnam to Australia. In the eastern Pacific they have been found from southern Baja California, Mexico, to Ecuador. They have been recorded repeatedly in the Potomac River, and they have a semi-permanent population in Lake Nicaragua. Bull sharks live in warm coastal water around the world, in bays, estuaries, rivers and lakes, and this is the water the tags keep showing.

Words to know

• satellite: space-tracked
• residency: staying put
• estuary: river mouth