Gondolas were present in many parts of the country during the 20's. Dozens could be found in California and Florida.
Most of the gondolas in the US at that time were authentic Venice-built craft, but there were some exceptions. These were two good looking boats, but based on the bow shape and the cambered gondolier's deck, I believe they were replicas.
No forcole are visible so one can conclude that the boats are either poled (after all, you can't see a blade at the end of either of those remi), the gondoliers are paddling, or they are using their remi as rudders to steer motorized gondolas.
The boats are interesting but I must say that I am most intrigued by the gondoliers; they don't look like Venetians. They're wearing knickers with no shoes and they appear to be of African descent. Since this operation was in Miami, I can't help but wonder if these guys were originally from a Caribbean island. So many cool gondola operations have come and gone over the last 200 years here in the United States, and unfortunately we don't know everything there is to know about most of them. In cases like this one, we can only guess about things based on photos like the one above.
In my experience researching gondolas of the past, I've found the best source of info to be post cards. We can learn so much from post cards. Often they are just a single image with one or two lines of text, but they are a view into the past. I've been collecting post card images of gondolas for a while now and while looking through them, I found two more images of the same two barefoot gondoliers and their boats.
The Flamingo was built in 1920 and closed in 1950. Overlooking Biscayne Bay rather than the oceanfront; the hotel was home to speed boat regattas and other spectacles. I'll be in Miami in March, You know I won't be able to resist a little research there.