From the waist down, I might go with something like L.L. Bean's Dryskin Guide Pants ($125), which are wind and water resistant. Or, some light waterproof, breathable pants such as Marmot's Precip Pant ($69). And throw in an insulated seatpad of some sortotherwise your butt is gonna freeze in that boat.
The tough call is footwear. Odds are good your feet will get wet, so I'd go with something like this: warm socks, such as SmartWool Hiking Socks ($16), then a pair of Gore-Tex socks ($40) or some made from SealSkinz ($30). Finally, you'll want shoes that can take some water, such as the Adidas Hellbender ($85). Your feet will stay warm and dry, but you'll also be able to stick them in the water as needed.
Happy eagle watching!
Filed To: Snow Sports