Questions about Mute Swans

My question is in two parts.

We have two families of Mute Swans living on two small man made lakes nearby. A few months ago, the Cob on lake 1 was killed in an accident just before the cygnets were hatched, leaving the Pen to take care of them alone. The Pen on lake 2 was nesting but the Cob would continually go to lake 1 where the other Pen was with her 4 cygnets. A local man would go into the lake in an attempt to chase the intruding Cob back to lake 2. A few weeks ago two new cygnets arrived on lake 2.

The same man then put a small raft made from wooden pallets in the middle of lake 1 hoping that the swans would adopt it as their sleeping place at night where they would be safe from predators like cats, dogs and foxes.

My question is in two parts.

1) While well intentioned, is this man right to interfere with nature by trying to chase the swan back to the other lake?

2) Since swans can sleep on the water, does the "raft" make any sense?