I have only been mammal watching in New Hampshire once, when I visited the Esther Currier Wildlife Management Area, near New London, in December 2013, after reading Vladimir’s report. I wasn’t as lucky as he was, though it was well below freezing, there was snow on the ground and freezing drizzle which didn’t help I am sure. I tried though, but during four hours in the afternoon and after dark I didn’t see any mammals.
Northeast USA & Quebec: Mihir Zaveri’s note includes an American Marten in New Hampshire, Beavers near New York City & Belugas in Quebec.
White Mountains, 2018: Venkat Sankar, 1 day & 5 species including Woodland Jumping Mice, Snowshoe Hares and a Long-tailed Weasel.
Quebec, Ontario and a bit of New Hampshire, 2013: Vladimir Dinets, 1 week & 26 species including Star-nosed Mole, Red (Algonquin) Wolf, Marten and Northern & Southern Bog Lemmings.