Staff at the zoo are feeding treats to Speedy, 70, Tom, 40 and Shelly, 30 to make them exceed their normal plodding speed of less than 1mph as they cross a new, larger pen, the Daily Express reported.
Keeper Kris Hern said that they use a target and the tortoises’ favourite foods.
They hold the target a few centimetres in front of them and when they touch it with their nose and feed them.
They then move the target further away and repeat the process.
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