The bull shark, Carcharhinus leucas, is a shark commonly found worldwide in warm, shallow waters along coasts and in rivers. The bull shark is known for its aggressive nature, predilection for warm shallow water, and presence in brackish and freshwater systems including estuaries and rivers. The bull shark can thrive in both saltwater and freshwater and can travel far up rivers. They are probably responsible for the majority of near-shore shark attacks, including many attacks attributed to other species. The name bull shark comes from the shark's stocky shape, broad, flat snout, and aggressive, unpredictable behavior. The bull shark is commonly found worldwide in coastal areas of warm oceans, in rivers and lakes, and occasionally salt and freshwater streams if they are deep enough. It is found to a depth of 150 metres (490 ft), but does not usually swim deeper than 30 metres (98 ft). In the Atlantic, it is found from Massachusetts to southern Brazil, and from Morocco to Angola. In the Indian Ocean, it is found from South Africa to Kenya, India, and Vietnam to Australia. Bull sharks are large and stout, with females being larger than males. Adult female bull sharks average 2.4 m (7.9 ft) long and typically weigh 130 kg (290 lb), whereas the slightly smaller adult male averages 2.25 m (7.4 ft) and 95 kg (209 lb). Bull sharks are wider and heavier than other requiem sharks of comparable length, and are grey on top and white below.