BOULDER, Colo. (CBS4) – A woman whose dog was killed by a coyote on Thursday in Boulder says she thought the pet was playing with another dog at first.

The woman let her dog off-leash on the on Bear Canyon Trail in the Boulder Mountain Parks system for a few minutes to go in the water at Bear Creek at noon.

Maddie — an 8 pound, fluffy white dog — began to “nuzzle” with what the owner thought was a small German shepherd, according to a ranger incident report.

By the time the owner realized Maddie had met a coyote, it was too late. The coyote had the dog in its mouth and took off.

Those who walk the popular Boulder trail, which connects to Boulder’s Mesa Trail, say coyotes are a common sight.

“There are coyotes around here all the time,” dog walker Patrick Caffrey said. “As far as we go, we’re on leash, and that’s what we’re going to stick to. I feel badly for the lady losing her dog. It happens on a regular basis though around Boulder County.”

“We’ve seen quite a few of them,” said Dave Lund, another dog walker. “They have no fear. They will come right up and approach you, even with bigger dogs like these.”

Several Good Samaritans and an open space ranger spent a few hours looking for the dog.

The ranger searched a coyote den where one had been spotted, but there were no signs of Maddie.

The ranger also posted three advisory signs (in addition to the signs that already warn dog walkers at the trail heads) to let people in the area know about the recent wildlife activity.