I'd have to look to which exact derailers are installed, but yes, they are stock. Most velos have a mtn bike style setup because we usually want as large a gear ratio as we can get.
And DrIsotope is correct. It's a very long chain (recumbents typically have about 3x the chain length of a DF bike). That probably helps. I've gotten some advice from other velo owners and the 61T up front is about as large as I can go with the stock chain.
I would like to try a Rohloff someday, but those are pretty pricey. I'm more inclined to probably go with a ~80T single up front, and get a Schlumpf Mtn drive.