Teresa and Tweeters,

You said...

....I'm interested in your impression of how a "zoo duck" would
behave. These ducks were avoiding people, and not looking for handouts.
They were not anywhere near the boardwalks or land, and were staying to
marshy areas....I would have expected an escaped duck to be
looking for a feeding....

Captive bred waterfowl can be very tame if they have grown up associating people with their only source of food. But in many waterfowl collections, the birds are fed "free-choice" and are kept in rather natural ponds where they have access to alternative food items. When there is plenty of food available they don't need to rely on handouts, even when they are used to being fed on a regular schedule in a predictable location.

....I was also surprised to see
three together - must have been a pretty big hole in the fence!!

Perhaps they are full-winged and simply flew out of an open topped pen that was designed to contain birds that had been rendered flightless, by pinioning or wing-clipping.

Greg Toffic