Continuity mistake: The Black Stallion was played by a horse with white markings; it's occasionally possible to see them under the black dye, especially during the desert scenes.
Factual error: The toy horse on Alec's shelf is a 64 Black Foundation Stallion, available from Breyer between 1977-1987. But the film is set over thirty years earlier.
Revealing mistake: In the closeups the boy is holding a large leaf of seaweed to offer the stallion. But in the long shots at the waterfront he extends an empty hand with no seaweed visible.
Answer: Alec collected rain water whenever he could.
raywest