State wildlife officials say a mountain lion killed at least one dog as well as another cougar in Boulder Canyon near Nederland this week.
Jennifer Churchill, a spokeswoman for Colorado Parks and Wildlife, said a man who lives on Magnolia Road found his pet Doberman and a mountain lion dead on his property Tuesday.
Churchill said the dog was often let loose on the property.
"We want to remind people that lions will go after unattended dogs, especially in areas where there are deer," Churchill said. "We do have lions that will key in on pets, since they are easier prey than deer, so keep them safe."
As for the other mountain lion, Churchill said it was a previously collared animal that was part of the state's study program. She said not much is known about why mountain lions would attack each other.
"It's something that has come up a couple times in the study," she said. "We're always getting new information from the study about how lions interact with each other."
Churchill said there have been other reported incidents of dogs going missing in the area, and there was also a dog killed south of Nederland that may have been a victim of the same mountain lion.
Abe Russell said his 6-year-old English bulldog, Tank, was killed by a mountain lion Monday. On Monday morning before he went to work, he said, he did not see or hear his dog Tank.
Russell said he and his Great Dane went looking for Tank, but about 40 feet from his house he turned the corner to find a large mountain lion had leaped the fence into his backyard and was just a few feet away with Tank's body.
"It was pretty traumatic," Russell said. "To not notice it and to walk up to within 4 feet of one is terrifying."
Russell said he wanted to back up, but his Great Dane started to bark at the cougar and he was worried the lion would kill her, too. So he picked up a stick and jabbed the lion in the neck until it ran off.
It was a frightening experience for Russell, who said he had never seen a mountain lion in his nearly 10 years living on Magnolia Road.
"It's one thing to know you live in mountain lion territory and another thing to know there is one here right now and hunting," Russell said.
Churchill said that because the mountain lion has not attacked a human, officials are not now looking to relocate it.
"An animal killing another animal is part of the natural cycle, and we generally do not intervene," Churchill said. "If it has an encounter with humans or an animal officer feels it is getting too comfortable near people, we may remove it. But there is not any need at this point to try and relocate the lion."
Russell said he reported the incident to Colorado Parks and Wildlife. He said he understands the mountain lion is only trying to eat, but rangers should consider relocating it.
"A single pet being killed is rough, but two pets within half a mile of each other? In that scenario, I think they should do something," Russell said.