Visit Sleeping Bear Dunes National Lakeshore in Michigan and you might expect to see a variety of ducks, belted kingfishers, some deer, raccoons, and perhaps catch the laugh of a loon.

But cougars?

Although these tawny cats have been documented in Great Plains and Midwestern states in recent years, they are not typically associated with the national parks of the Midwest. But dozens of folks -- including the park's law enforcement chief and a volunteer -- claim to have spotted cougars in the lakeshore in recent years. Is it wishful thinking, or misidentification?

"Over about the last almost five years now we've been averaging around 15 pretty good sightings a year," Ken Hyde, the lakeshore's wildlife biologist, tells me. "We've never been able to verify any of those."

Not only have there been numerous sightings, but many were close at hand or involved someone who knows the difference between a bobcat, which does live in the lakeshore, and a much larger cougar. In one instance, the lakeshore's law enforcement chief spotted what he thought was a cougar while driving home one night. Another case involved a park volunteer who came within several feet of what she believed was a cougar on a hiking trail.

"I've had two or three others who have seen a cougar laying down or run across a trail, but probably a majority of (the reports) are a cougar running across a road," says Ranger Hyde. "Then, of course, the (state) Department of Natural Resources and everyone else says, 'Well, if they're running across a road, eventually one of them should have been hit. Why have we gone several years without any of them being hit?'"

Almost every time a sighting is reported, rain falls before Ranger Hyde can reach the site, making it impossible to spot any tracks. When he hears of a deer kill, coyotes manage to clean it up before he can arrive to determine what killed the animal.

A few winters ago, from November 2004 through April 2005, lakeshore biologists conducted a winter survey for cougars. More than 850 "camera nights" failed to turn up an image of one of the felines (although they captured a representative array of just about all of the lakeshore's known predators), and nearly 500 kilometers of track surveys failed to turn up a cougar paw print, scat, hair, or kill site.

The biologists' conclusion? There is no evidence that cougars roam Sleeping Bear Dunes National Lakeshore.

We investigated four cougar reports and one report of cougar tracks during February and April 2005. In each instance, we determined the specific location of the observation based on a detailed description by the observer or by the observer taking us to the actual location. Locations were searched within 24 hours of reporting; inclement weather (e.g. rain, snow) did not occur between the observations and our investigation, the biologists reported. No evidence of cougars was found at any of the five locations. Of the reported cougar observations, we found bobcat tracks at one location, coyote tracks at one location, and bobcat and coyote tracks at two locations. The reported cougar tracks, shown to us by the individual that made the report, were made by a domestic dog.

And yet the reported sightings persist. And they're not localized in one section of the lakeshore, but rather all over it, says Ranger Hyde. "We'll get maybe two or three sightings in a general area, and then they're gone," he says. "And then we have them show up somewhere else."

So for now the mystery continues. This summer the wildlife biologist hopes to conduct a survey for the cats, but that won't be easy.

"During the summer the leaves are on these northern hardwood areas, and it's a jungle back in there," says Ranger Hyde.