Pekin ducks are a popular domesticated duck that are typically used for the commercial production of eggs and meat.
They were originally bred from mallards in China and imported to the US in the late 1800s.
It appears that this one had gone native and decided to explore it's wild roots. It was accompanied by 2 to 3 male mallards.
I also got a couple of shots of hooded mergansers. Hooded mergansers are the second smallest in the merganser family and the only merganser that lives exclusively in North America.
There were also some common mergansers on the river but they were too far away to get any descent pics.