It’s hard to spot some kinds of animals—they’re secretive, or they’re active at night, or they live in remote places. This spring, scientists were delighted to find multiple images of two secretive mammals, the American marten (Martes americana) and the Grey fox (Urocyon cinereoargenteus), in photos captured by motion-sensor cameras set up in the Andrews Forest. The marten and the fox are seldom seen, even in a place like the Andrews Forest where researchers travel deep into the forest, morning and night. Although marten and grey foxes typically prefer older and undisturbed forests, they are relatively uncommon at the Andrews Forest. Marten in Oregon are typically found at higher elevations or along the coast. Both species are nocturnal during certain parts of the year and require hollow logs, burrows, or tree cavities for resting and denning. Both species feed primarily on mammals like squirrels, chipmunks, and hares, but their diets can include fruits, nuts, birds, insects, and carrion. Because marten and grey foxes are shy mammals, motion cameras are an important tool for surveying them and other mammals that are otherwise hard to see. Research at the Andrews Forest on mammals, including spotted skunk and weasels, continues, with a goal of learning more about each species, the role each plays in the ecosystem, and how their habits may be changing with a changing climate.