What knot can also relieve load from a weak spot in the line?

The sheepshank is specifically designed to take up slack in a line and can effectively relieve load from a weak spot. This knot is useful in situations where it is necessary to shorten a length of rope without cutting it, keeping the tension balanced while allowing for adjustments. When tied correctly, the sheepshank maintains the integrity of the line by redistributing the load away from the damaged section. This makes it an ideal choice for managing lines that might have frayed or weakened areas, preserving the rope's overall function and safety during operations at sea.

Each of the other knots mentioned serves different purposes. For example, a monkey fist is primarily used as a heavy weight at the end of a rope, while a Spanish bowline creates a secure loop that does not slip. The barrel hitch is useful for lifting or securing barrel-shaped objects. While these knots serve their specific functions well, they do not provide the same capability as the sheepshank to relieve load from a compromised area in the line.