Baby chickens walk on water

When baby chickens are in (or rather on) a water source block, they appear to walk on it, not swim. They move up and down as expected, but they never go below the surface of the water. Moving them around on the water produces the clicking sound of a chicken walking on land. The same sound occurs when they move voluntarily. Adults seem to be unaffected. Upon growing up the chicks behave like normal adults in water.