During a lull between snowstorms, we took a walk at Back Bay National Wildlife Refuge.

The beach was clear, but large sections of the bay were frozen, as were all of the ponds. Winter normally brings a few frosty nights to our area, but prolonged bouts of sub-freezing temperatures are rare.

Most of the over-wintering birds had deserted the refuge, and the few that remained seemed confused.

Mallards were out, walking on the ice. Something about the way they moved — one careful step at a time, watching their feet, pausing here and there to probe the ice — reminded me of television detectives inspecting a crime scene.

Other flocks had given up and opted to sleep until the ice thawed.

With the refuge so quiet and still, every sound and movement drew my attention. On a normal day I would have missed the mockingbird on the parking lot fence and the small heron huddled near the road.

I doubt I would have missed the deer, though. Three of them edged nervously out of cover near the Visitor’s Station, crossed an open patch of lawn, and disappeared down one of the trails.

I wondered if the lingering snow had forced the deer to change their grazing pattern. Or maybe they wander through every day? Maybe snow, even rare twice-in-a-month snow, doesn’t affect deer the way it affects me. Maybe they don’t spend hours admiring the fresh fall, then more hours fretting over the slippery deck, half-frozen pipes, and cancelled appointments. Maybe they simply carry on, day after day, searching for nothing more complicated than grasses to eat, water to drink, and a warm, dry place to sleep.