Kirk did the butterfly out to Alcatraz and back.  3 1/2 hours.  The original plan was to go out, around Alcatraz and back, but the ebb current was too strong to allow Kirk to swim around the back of the island.  He reached the island at the southwest end.  He swam around the the southeast side attempting to make the turn around the back, however the current at the corner was too strong for his swim speed doing the butterfly.  He settled for a touch and go and headed back to the city front.