I can't recall any other time that I have ever seen the swans even remotely interested in their namesake boats.
As I walked across the bridge in the garden today they seemed a bit perplexed by the "naked" boats.
Hurricaine Earl was due to hit about midnight tonight and it's my guess that the swan part of these small but sturdy watercraft were taken into safe harbor for the duration of the storm.

Don't worry swans,
they'll be back....