reat white sharks are carnivorous, and primarily eat fish (including rays, tuna, and smaller sharks), dolphins, porpoises, whale carcasses and pinnipeds such as seals, fur seals and sea lions and sometimes sea turtles. Sea otters and penguins are attacked at times although rarely, if ever, eaten. Great whites have also been known to eat objects that they are unable to digest. In great white sharks above 3.41 metres (11 ft) a diet consisting of a higher proportion of mammals has been observed.^[16] These sharks prefer prey with high contents of energy-rich fat. Shark expert Peter Klimley used a rod-and-reel rig and trolled carcasses of a seal, a pig, and a sheep to his boat in the South Farallons. The sharks attacked all three baits but rejected the sheep carcass.^[17]

The great white is regarded as an apex predator with its only real threats from humans. Although their diets overlap greatly, great whites do not seem to directly compete with orcas and there are few reports of encounters between them. The average orca is larger and faster which is probably why the sharks do not bother to compete. However in one famous incident a female orca killed a subadult great white and her calf feasted on the shark's liver.^[18] Pods of dolphins can kill a great white shark through mobbing behaviour in which the dolphins ram the shark. Great whites are also sometimes preyed on by larger specimens.

Great white breaching to catch a Cape Fur Seal

Great white sharks' reputation as ferocious predators is well-earned, yet they are not (as was once believed) indiscriminate "eating machines". They typically hunt using an "ambush" technique, taking their prey by surprise from below. Near the now-famous Seal Island, in South Africa's False Bay; studies have shown that the shark attacks most often occur in the morning, within 2 hours after sunrise. The reason for this is that it is hard to see a shark close to the bottom at this time. The success rate of attacks is 55% in the first 2 hours, it falls to 40% in late morning and after that the sharks stop hunting.^[19]

The hunting technique of the white shark varies with the species it hunts. When hunting Cape fur seals off Seal Island, South Africa, the shark will ambush it from below at high speeds and hit the seal at mid-body. They go so fast that they actually breach out of the water. The peak burst speed of these sharks is largely accepted in the scientific community to be above at least 40 kilometers per hour (25 mi/h), however further precision is still regarded as speculation and obviously depends on the individual shark. ^[20] They have also been observed chasing their prey after a missed attack. The prey is usually attacked at the surface.[