The increase in sightings also may be attributed to technological advancements.
The most recent confirmed sighting, near the junction of highways 160 and 19 in Alton, was captured on a game camera.
Missouri Department of Conservation biologist Jeff Beringer said experts could not determine by the camera image the age or sex of the mountain lion, although he suspects it to be a male passing through in search of a mate.
It is the third confirmed sighting in the Missouri Ozarks since March, and the ninth in the past 10 months. On March 9, a motorist near Rover in Oregon County saw a mountain lion cross the road and get tangled briefly in a barbed wire fence. A cotton ball-sized tuft of hair taken from the fence traced that cat to South Dakota.
Both August sightings were images caught by game cameras -- one near Mountain View on the western edge of Shannon County and the latest sighting near Alton in Oregon County.
Beringer, who is with the states's mountain lion response team, said the two sightings could be the same animal, but without physical evidence to check DNA, it is only speculation.
Mountain lions have been traced from a Black Hills, S.D., colony of mountain lions to as far east as Connecticut. Beringer speculates the cats are likely young males moving through in search of females and hunting territory.
"Typically, they don't stay around," Beringer said. "If they don't find a mate, they keep moving."
The two camera images from August did not capture the animals at the right angle to determine if they are male. The shots also were too dark to see if barring still is present on the cats' front legs. The barring is most evident on young animals, and is gone by the time they reach two years.
Young cats disperse from their natal homes at about 15 months of age. Depending on her health, a mother cat can have four or five kittens in one litter annually. The kittens do not have a high survival rate, however, Beringer said.
When the young cats leave South Dakota, they must go a long way before they find suitable habitat, such as remote Ozarks' areas, where game and shelter is ample. Mountain lions are typically shy, and will avoid humans and barking dogs.
Rex Martensen, also with the conservation department's mountain lion response team, said the images on the cameras do not appear to be that of captive lions that have escaped.
Thirty-two mountain lions are licensed for captivity in Missouri.
Captive cats tend to be overweight, Martensen said. They also will have wear marks on their elbows, such as a dog has, from laying on concrete or other hard surfaces.
Captive mountain lions also have plaque on their teeth from eating commercially prepared food. Mountain lions actually prefer to kill their food, Martensen said, although they also will eat dead game in captivity, Martensen said.
Sometimes, owners have arrangements with local conservation agents to acquire road kill, Martensen said.
Besides mountain lions, about six black bears are licensed for captivity in Missouri, as are about a dozen wolves. Black bears are probably the easiest to feed in captivity, Martensen said, because they will eat anything, such as scraps, although they need a lot of it. Black bears can reach 400-500 pounds.
Wild animals held in captivity must be caged at all times, Martensen said. The cages are inspected by conservation agents to verify sturdiness and that the animals have adequate space.
Martensen said Missouri did not begin protecting mountain lions until about the 1940s or 1950s. The last wild mountain lion killed in the state was in 1927 in the bootheel.
The next mountain lion sighting was not reported in Missouri until 1994 when two raccoon hunters treed and shot a small adult female near Peck Ranch Conservation Area in Carter County.
The carcass was never recovered, but a photo was obtained of the animal on a truck tailgate. The hunters were fined $2,000 each.
Mountain lions are a protected species that may only be killed if they attack or kill livestock or domestic animals or threaten human safety.
From 1996-2006, about one mountain lion per year was reported in Missouri. In November 2010, a landowner in Platte County photographed a mountain lion.
Since then, eight more confirmed sightings have taken place, two of which were in Oregon County and one in Shannon County. Most of the sightings are by motion-activated game cameras.
Beringer said game cameras could be contributing to the increase in sightings because inexpensive cameras are readily available, and not necessarily an indication that more mountain lions are in the area.
"Every other deer hunter out there now has a game camera," Beringer said.
Beringer said it is possible the mountain lions have always been in the Ozarks, and have remained hidden for generations.
Martensen said people should not run if they encounter a mountain lion, which can trigger a response mechanism in the cat to chase.
The best thing to do is to make yourself appear larger by spreading out your arms and backing away slowly, Martensen said.
"They don't like to fight with something if they don't think they can win," Martensen said.
For more information, go to www.missouriconservation.org and search for "mountain lion."