A sign warns visitors about a fiesty fox in Grand Teton National Park's Lizard Creek Campground. (Courtesy of Emily Davis/Grand Teton National Park)

Sometimes, it was a solitary sneaker or flip flop disappearing. Sometimes, a full pair was missing. But the trend was undeniable: Someone was stealing campers' shoes.

When the number of lost items hit 19, park officials decided to take action, and by that point, they had a prime suspect.

"Wanted For Grand Theft Footwear," they scrawled on signs, complete with a black-and-white sketch of a sly fox holding a tennis shoe in its mouth. Some signs mentioned "aliases" for the animal, such as "Sneaker Snatcher," "The Midnight Mismatcher" and "Swiper the Fox."

FILE: A red fox roams in the parking lot at Jenny Lake Boat Landing inside Grand Teton National Park in Wyoming on March 15, 2024. (REDA/Universal Images Group/Getty Images)

Below the first sign, another sign read "Days Since Last Fox/Shoe Incident" and asked park visitors to "beat the record" by storing their footwear inside a tent or vehicle.

But the fox's thievery has continued, with the tally up to 32 shoes as of last week.

A recent visitor commented on the park's Instagram post about the fox, saying, "We can confirm!! We camped 2 nights at Lizard Creek last week and the fox got 3 shoes while we were there. One was found down the road, but was pretty useless as the matching shoe was gone forever."

Park officials believe the signs may have had the opposite effect, with campers potentially leaving out even more shoes in hopes of seeing the fox. But while a campground sighting may seem cute, it's actually harmful to wildlife. When wild animals become habituated to the presence of people and their food, they can end up needing to be relocated or euthanized.

Grand Teton National Park is tracking the number of days since the last shoe incident in Lizard Creek Campground. The tally, which previously included 19 shoes, is up to 32 as of last week. (Courtesy of Emily Davis/Grand Teton National Park)

"Habituation is when a wild animal loses its natural wariness of humans," Emily Davis, a park spokesperson, wrote in an email to SFGATE. "Foxes that live near developed areas can become habituated to people."

It's unclear why the animal might be interested in shoes: The park has speculated that the fox might be using them as toys or nesting material. Other animals are drawn to human clothing, such as backpack straps, if the items have absorbed salty sweat.

"The fox may be attracted to the scent or taste of shoes, or it could be treating them like toys," Davis wrote. "Interestingly, last year at a den site near the airport, park staff discovered a Kong dog toy, which is another recent example of how human items can end up in the paws of wildlife."

Lizard Creek Campground in Grand Teton National Park. (National Park Service)

Feeding or encouraging contact with wildlife puts animals of all species at risk. Grand Teton National Park is asking visitors to store shoes, food and scented items securely, as well as avoid baiting wildlife. If a fox shows up, "scare, don't stare," according to the park's Instagram post. Report behavior to a campground host or park official, and don't approach the fox. "Make noise and encourage it to move along," the post continued. "Wild animals need to stay wild."

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