None... Titanic was too far from any shoreline for anyone to be able to swim back.
Yes and no. If you count Nick at Nite, yes. However, as far as a late night block of adult cartoons, no.
So far as I know, it's actually illegal to swim in the Seine.
Magellanic Penguins eat small fish and cuddlefish. Because they have to swim out far, they are being damaged by currents and pollution, making them an endangered species.
As far as I can tell from other sources, a donkey can easily carry 30% of its own weight, and it is said that some donkeys are forced to carry double their weight, but this will probably hurt them alot. I would say 30% is a good rule of thumb.