Sharkwatch SA Blog

White sharks are part of the fish family, so they must be 'cold-blooded', right?  Actually, white sharks are much more complex than you may think. 

An animal that is 'cold-blooded' means their inside body temperature is dependent on the environment they are in.
For example, a snake is cold blooded, so its body temperature fluctuates with the day or even whether or not they are in the sun. That is why on chilly days, you can often find snakes sunning themselves, literally charging up their body temperature.
Us humans are 'warm blooded' which means we have a stable body temperature (37 C°) regardless of what the weather is doing outside. We maintain this with a much higher metabolism (we have to eat many times a day, whereas a snake can go days without eating). 



White sharks are "lamnid sharks" which have a unique system called a 'counter current heat exchange,' keeping their body warmer than the outside conditions by +/- 10-15 C°. So if a white shark is in 9 C° water, its body temperature will be +/- 19-24 C° and so on.
The generator of all this heat comes from the long muscles running down the length of their bodies, which charge a core of 'white muscle' ready for quick bursts of energy even in cold environments, which is why they are the apex predator of our temperate seas. We call this, “heterothermy”. Why would a white shark need a built in turbo booster? Well...