Fortunately I’m close to one of the Great Lakes where we get large numbers of ducks in the winter, so while the woods are quiet it’s always still worth getting out to the water.
Winter is a great opportunity to get observations of under-observed taxa - I’ve spent many hours waiting at bus stops in the winter, scavenging the bark of nearby trees for lichens and the ground for mosses and weeds. During warm spells invertebrates will still come up; if the temperature is above 0C and the ground starts to thaw then you can find millipedes and springtails etc. in leaf litter and under logs.