From sniffing out turtle eggs to keeping mountain goats out of parking lots, four-legged rangers carry out many duties that help preserve national park resources and make sure visitors have a pleasant and safe park experience.

Cooper and Charlotte, Lake Mead National Recreation Area, Arizona and Nevada

Lake Mead National Recreation Area allows dogs on leashes, but dog owners have to follow a number of rules and safety precautions, from picking up after their pets to putting booties on their paws when the pavement gets too hot to making sure they are not left alone at campgrounds. “Especially small dogs that look like a rabbit to a coyote,” said Christie Vanover, Lake Mead’s public affairs officer.

With about 7 million visitors a year, rangers must do plenty of outreach to ensure these rules are followed. Enter Cooper and Charlotte, the park’s two “bark rangers.” The two meet kids in classrooms and visitors at park events.

Cooper, a Yorkshire terrier wearing a park ranger outfit made by his owner’s mother, is the star of the show. “He’s such a cute guy,” Vanover said. “He just draws the crowds.” Charlotte welcomes attention from visitors, but Cooper usually stays in a ranger’s arms out of self-preservation. “He’s so tiny that people could step on him,” Vanover said.

Charlotte does not limit her duties to educating visitors about proper dog owner etiquette. A certified therapy dog, she helps park staff process stressful situations, such as dealing with visitor fatalities (drownings are not infrequent at the park).

“Being with a dog is definitely soothing, and it helps us re-center,” Vanover said.

Ridley, Padre Island National Seashore, Texas

Kemp’s ridley sea turtles are the most endangered sea turtles in the world. Staff at Padre Island have helped to boost the animal’s populations by collecting eggs from their nests to protect them from predators and other hazards. The problem is that female turtles only spend about 45 minutes laying their eggs before going back to sea, and the wind often wipes out their tracks, making nests difficult to find on a shore dozens of miles long.

“It’s like a needle in a haystack,” said Donna Shaver, who has led Padre Island’s turtle recovery program for decades.

About 10 years ago, Shaver thought a canine with a strong sense of smell might be able to help her find turtle nests. “The coyotes find them just fine,” she remarked.

She trained the family’s puppy, the appropriately named Ridley, to identify the scent of turtle eggs. The diminutive Cairn terrier didn’t take long to demonstrate his effectiveness. When rangers couldn’t locate a nest on the beach, they put him to the test.

“He found the nest cavity right away,” Shaver said. Since then, Ridley has helped park staff find several nests, allowing them to release more hatchlings and boost the species’ fragile population.

At 11, Ridley is “in the twilight of his career,” Shaver said. The Kemp’s ridleys’ hatchlings are in good hands (paws?), though. Shaver said Ridley’s successor Kayleigh is “as good if not better than Ridley.”

Ken Franklin, Independence National Historical Park, Pennsylvania

Independence National Historical Park welcomed more than 5 million visitors last year, and keeping the crowds safe is a big job. For that task, park rangers can count on Ken Franklin, a 6-and-a-half-year-old German shepherd who can detect a variety of explosives.

Ken was trained by the Philadelphia Police Department for 10 weeks, and he must renew his training certification every month. Park ranger Nick Iannelli, his handler, also does a lot of training at home, using Ken’s favorite tub toy as a reward every time his dog finds the small amounts of explosives he’s searching for. Ken also goes to schools and meets with Girl Scouts, Boy Scouts and junior rangers to demonstrate his talents and educate children about safety.

And when he’s not on duty, he really gets to leave his work behind. “I kind of let him relax and be a dog,” Iannelli said.

Editor’s note: K9 law enforcement ranger Ken Franklin, “one of the prime protectors of our nation’s ultimate symbols of liberty and freedoms,” died from a sudden illness on November 13, 2019, according to a statement from Independence National Historical Park. “His presence and paw prints will be deeply missed at Independence National Historical Park, and his accomplishments will continue to be respected with high honor as an impeccable bark ranger,” the statement added.

Tobias, Glacier National Park, Montana

The region around Glacier National Park is part of the headwaters for the Columbia River, which is the United States’ last major river basin not contaminated by invasive mussels, said Caryn Miske, executive director of the Flathead Basin Commission.

“It’s a big deal,” Miske said.

Keeping zebra and quagga mussels at bay is crucial. Human inspectors rely both on sight and touch to detect the shellfish on boats and trailers, but it’s not a foolproof approach.

“Mussels are hard to find,” Miske said. “You’re often looking for something that’s as big as a speck of light.”

That’s where dogs come in. They use their scent to find the mussels their handlers missed. Tobias, a Labrador, went through rigorous training and proved to be a great mussel detector. “The accuracy with which they can smell is incredibly good,” Miske said.

Tobias served a few times at Glacier, but he worked mostly outside the park, including at the nearby Blackfeet Indian Reservation. The program was suspended because of funding restrictions, but Miske hopes she can resume it next year.

Geese Police of DC, National Mall and Memorial Parks, Washington, D.C.

The National Mall, which runs from the Lincoln Memorial to the U.S. Capitol, has been called America’s front yard. In this open space, visitors can honor democracy, America’s presidents and the veterans who gave their lives for our country. The area’s resident Canada geese weren’t treating this hallowed ground with the respect it deserved, though.

“You couldn’t walk down the Reflecting Pool without stepping on a ton of poop,” said Doug Marcks, co-owner of Geese Police of DC.

So for more than two years, Marcks has been patrolling the Mall with one of his border collies to shoo away the birds. The dogs run after the geese and don’t hesitate to jump in the water to chase them away, often prompting clueless passers-by to ask Marcks why his dogs are not on a leash.

Marcks varies the times of his walks to keep the geese on their toes. “If I show up at 9 a.m., the geese will be there at 9:30,” Marcks said. “They’re pretty smart birds.”

Happy, Flight 93 National Memorial, Pennsylvania

The Flight 93 National Memorial often elicits strong emotions among visitors, said MaryJane Hartman, the chief of interpretation and visitor services at the site where on September 11, 2001, a hijacked plane crashed, killing all its passengers and crew. Hartman said some visitors are overwhelmed with distress or anger as they relive the events that unfolded on that day. For almost four years, one particular volunteer helped those visitors process their feelings: Happy, a golden retriever and certified therapy dog.

“They could sit on the bench and pet the dog, and they found it very therapeutic,” Hartman said.

Happy’s gentle demeanor helped visitors calm down, which often led them to open up, Hartman said. Happy went through some trauma himself. Before suffering from a cancer that sadly took his life earlier this month, he had undergone a total hip replacement after Marsha Dulz rescued him from a shelter. Perhaps out of empathy, he always greeted visitors in wheelchairs first, Dulz said. He would also stand up every time a veteran in uniform approached.

Happy’s impact will be long-lived, as he touched thousands of visitors during his service. Over the course of almost four years, Happy volunteered 76 times at the memorial for as long as seven hours a day. He retired from his duties at the memorial in September 2015, but he later continued to pay regular visits to a nursing home.

Nero, Redwood National and State Parks, California

Redwood National and State Parks law enforcement ranger John Craig had had dogs growing up, and it was his lifelong dream to work with one. He successfully made the case to his superiors, and in September, Nero, a German shepherd, arrived from the Netherlands. Nero and Craig underwent seven weeks of training to develop Nero’s skills as a narcotics detector and criminal tracker. The duo also learned to trust each other.

“I had to learn to speak dog and read his body language,” Craig said.

The two don’t limit their duties to the park itself and often collaborate with local law enforcement, searching for drugs in vehicles or chasing down suspects. While Craig said he can’t discuss the details of Nero’s involvement in drug operations, he said his dog has already proved invaluable in helping to catch criminals.

“Nero and I were able to successfully track one who was hiding in a bush,” Craig said.

Python Pete, Everglades National Park, Florida

Lori Oberhofer knew beagles had been used in Hawaii to detect invasive brown tree snakes, so she thought maybe one could help sniff out the Burmese pythons that were wreaking havoc in the Everglades’ fragile ecosystem. A beagle’s nose can be a better tool than human eyes because pythons’ coloring makes them difficult to spot in the Everglades. Oberhofer ordered a beagle puppy from a breeder in Missouri, and 8-week-old Python Pete began training right away with a baby python whose scent he became familiar with.

“I started hiding it around the house, and he got so excited every time he found it because he got a treat,” the park wildlife biologist said.

Word got around that Python Pete was good at finding snakes, and he and Oberhofer ended up spending more time talking to reporters than looking for pythons.

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Estimates for the number of pythons in the broader Everglades ecosystem run as high as 100,000, and the snakes have few natural enemies to limit their populations. Organized searches, traps and the use of tagged females to locate breeding partners have had little impact. The job was just too big for one Python Pete.

“There were so many pythons out there that it would have taken an army of Python Petes to even make a dent,” Oberhofer said. “It wasn’t his fault.”

Python Pete may not have ferreted out every python, but he’s had a lasting impact thanks to his star appeal, as a lot more people have become aware of Everglades National Park’s python problem. After a four-year career, Python Pete retired in 2008 and moved to Kentucky where pythons are few and far between. Oberhofer said she hasn’t ruled out using detector dogs in the future, perhaps training them to identify the scent of pregnant female pythons to increase their impact.

Sled Dogs, Denali National Park and Preserve, Alaska

Denali is the only national park with its own kennels, which are home to 34 Alaskan huskies. These dogs attract about 70,000 visitors a year, and the park’s puppycam is a hit with remote admirers. But the sled dogs are not there just for show.

“In the winter, they are the main form of transportation for rangers in the park,” said Jamie Milliken, the lead ranger at the Denali sled dog kennels.

Teams of eight to 12 dogs establish and maintain trails for winter visitors, carry scientific equipment and haul off trash as well as large debris such as timber from collapsed bridges. Each dog can pull the equivalent of 50 to 60 pounds, so a team can transport upward of 300 pounds in addition to the sled, the supplies and the musher. Unlike a snowmobile, a sled dog team will not be sidelined by a breakdown, as the load of an injured dog can easily be pulled by the rest of the team. What’s more, sled dogs can roam the park’s 2 million acres of designated wilderness where motor vehicles and aircraft are restricted by law.

The huskies accomplish it all on a diet of dry kibble — and balls of rendered poultry fat. “It looks nasty to me, but they love it,” Milliken said.

Montana, Abby and Ziva, Joshua Tree National Park, California

A few years ago, Alice Waltermire wanted to serve the community around Pioneertown, California, where she lived, so she, her husband Kirk and their dogs joined JOSAR, the search and rescue team of Joshua Tree National Park.

The training was intense, but now the Waltermires, border collie Montana, and bloodhounds Abby and Ziva are fit to rappel down boulders or scour the desert in search of missing hikers. The rescue dogs go out early in the morning or late in the day to avoid the most extreme heat. They wear booties if necessary and a vest soaked in water to cool off. All three dogs try to pick up the scents of missing persons from articles of clothing or the inside of a vehicle. Montana searches the area on her own, while the two bloodhounds stay on leashes and pull their handlers in the right direction.

Last summer, a little girl was missing for two hours in the park in 100-degree weather. “We gave Abby the scent, and she took off, and we brought the little girl back safe and sound,” Waltermire said. She congratulated Abby with a treat. “When they make a find, they get a steak all to themselves,” Waltermire said.

Oscar, Boston National Historical Park, Massachusetts

Oscar was destined to be a guide dog for the blind until he failed his training — he was too easily distracted by appetizing smells. “He failed because of his food motivations,” said David Pinkos, his handler. “I’m like that, too.”

But the 3-and-a-half-year-old yellow Labrador displayed great work habits, and Pinkos turned Oscar’s one weakness into an asset for his new job as detector of ammunition, guns and explosives.

“When he finds something he gets food,” Pinkos said. “He has to actually work to get fed.” The flipside? Oscar is always working. “I do training at home, because I have to feed him,” Pinkos said.

Pinkos and Oscar conduct regular sweeps in Boston National Historical Park, including the two-century-old USS Constitution, and inspect unattended bags. They also assist local police during large events such as the Boston Marathon and search vehicles for firearms. When Pinkos patrols an area with Oscar, who wears a vest with an arrowhead, they serve a dual purpose: reassuring visitors and discouraging would-be criminals.

“I let people know he’s there,” Pinkos said. “He’s kind of a deterrent.”

Gracie, Glacier National Park, Montana

Mountain goats and people are often way too close to each other at Glacier National Park’s Logan Pass, and it’s the fault of both humans and animals. Some visitors ignore warnings to keep their distance to get that perfect selfie with wildlife in the background. The goats like their salts, so they’re often looking to lick antifreeze leaking from vehicles on the parking lot. A recent study also concluded that mountain goats hang out near people because wherever humans are, there are fewer predators.

That gave Mark Biel an idea. As the manager of Glacier’s natural resources program, what if he could enlist the help of a dog to instill fear in the habituated goat population? “Gracie looks cute and fuzzy to us, but obviously to goats and sheep, she looks like a predator,” he said.

Thanks to funding from the Glacier National Park Conservancy, Biel and his 3-year-old border collie received training from the Wind River Bear Institute and started working as a pair last summer to keep mountain goats and bighorn sheep at bay.

“It worked pretty well from the get-go,” Biel said. “The sheep really don’t like her being there, so they’ll back away 30 to 40 yards.”

Biel found another use for Gracie. Deer often congregate near housing for park staff, and mountain lion sightings have increased as a result. So Biel and Gracie chase the deer away, hoping the mountain lions will follow.

“We’re just moving the grocery store where the mountain lions shop,” he said.

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