Whose backyard is it, anyway? When a wildlife camera is on duty, with its heat- or motion-triggered shutter at the ready day and night, the answer can be startling.

Sally Naser calls the animals recorded on the dozens of cameras she monitors for The Trustees of Reservations in Massachusetts “our wildlife neighbors.” At home, in our gardens, we may call them cute — or our herbivorous enemies. But more often than not, we don’t see them.

“There is wildlife all around us, whether you live deep in the woods or on an urban edge,” said Ms. Naser, the conservation restriction stewardship director for the Trustees, the nation’s first preservation and conservation nonprofit, with more than 26,000 public acres and another 20,000-plus private acres under conservation easements. “In back country and in front country, if you want to get this window into the wild, it’s out there for the camera to record.”

In recent years, the quality of wildlife cameras has improved, and prices have dropped. Often referred to as “camera traps” — as their main market has long been hunters wanting to locate that big buck — they have become essential scientific research tools, used to study animal behavior and assess populations, even in terrain as challenging as the rainforest canopy.

In a garden, a simpler setup can answer more straightforward questions: Who’s eating those bush beans? Who’s tunneling under the porch? And what’s going on at the bird feeder when you’re not looking?