Duck predator?

[youtubeminer]

I saw a thing that lives underwater in a swamp it looked like a mink but I took a little glace at it but it went under water what animal?

 

[tdepointe]

Most likely it was a mink, they do swim. Mink spend a lot of time in the water, they can dive deep and can stay under awhile. I have seen them eating fish.

Here is a link with some information on them. http://wildlifeofct.com/mink.html