WILLOW CREEK — A bull moose standing chest-deep in the Mattawamkeag River at dusk, water dripping from its antlers, is the kind of sight that makes visitors gasp. Starting this month, they can book a seat to see it.

Northwoods Outfitters launched guided moose-watching tours on Aug. 1, offering evening trips into the Mattawamkeag River watershed, where moose densities are among the highest in northern Maine. The three-hour tours, led by registered Maine Guide Julia Chen, use a combination of canoeing and riverside observation to spot moose feeding in the shallows.

“Moose are crepuscular — they’re most active at dawn and dusk,” Chen said. “We head out around 5 p.m., paddle quietly, and look for signs: tracks, fresh droppings, willows that have been browsed. When you find fresh sign, the moose is usually nearby.”

The tours cost $65 per person and include binoculars, life jackets, and a snack. Chen has led seven tours so far, with an average of two moose sightings per trip. One group spotted a cow with twin calves.

Maine has the largest moose population in the lower 48 states, estimated at 60,000 to 70,000 animals. Aroostook County’s density is among the highest, making Willow Creek an ideal base for moose-watching.

Tours run through October and resume in May. Chen said she plans to add dawn tours next spring.