Ally has a nose for wolves. Gator can sniff out grizzlies. And Tucker really knows his orcas. Or rather, what they’ve left behind.
Among the growing number of scat-detection dogs used to track wildlife by land or by sea, the canines employed by the University of Washington’s Center for Conservation Biology are showing that no technology can yet outdo their know-how for doo-doo.
Samuel Wasser, the center’s director, said feces is the easiest part of an animal to collect and a “treasure trove” of vital information. Apart from diet, scat can reveal the species, sex and identity of an individual through DNA, while released hormones can record an animal’s nutritional state, reproductive status and stress levels.
Dogs possess such an extraordinary sense of smell that they can distinguish among the feces of 18 species at once, Wasser said, making them ideal tracking aids for conservation biologists hoping to cover a lot of ground. Or water. Beyond helping document grizzly and black bear behavior in Alberta’s vast Jasper National Park, the dogs have located floating feces from endangered North Atlantic right whales in Canada’s Bay of Fundy and from the Pacific Northwest’s declining orca population. Remarkably, some of the poop snoopers perched on the bows of research vessels have tracked down whale scat more than one nautical mile away.
Wasser, who has embraced his nickname of “the guru of doo-doo,” highlighted his team’s findings and new ways to tap the domestic dog’s incredible nose during a recent conference organized by the Council for the Advancement of Science Writing. Some canines, he said, can match one scat sample to all others belonging to the same individual, a super-sensitivity that has proven invaluable in studying animals such as California’s minklike fishers and Brazil’s maned wolves – and a method that he said has out-performed even DNA tests.
For whales, he said researchers could examine the effects of Navy sonar tests by collecting scat before and after the underwater tests and looking for differences in the marine mammals’ stress hormone levels. In a subsequent telephone interview, Wasser also confirmed that his team expects to begin using detection dogs to identify pellets from spotted owls in the Pacific Northwest to help document remaining habitats.
The high-energy dogs used by his team, Wasser said, possess an insatiable desire to play fetch. Many were rescued from animal shelters – often because their obsessive personalities weren’t tolerated by previous owners. The excessive drive to play motivates the dogs to cover large distances in search of feces with the expectation of a 90-second period of play after each success. Wasser’s team works mainly with Labrador retrievers, but the researchers have trained breeds ranging from rottweilers to dachshunds.
“I wouldn’t want to own one because they’re obsessive-compulsive dogs. They want to play with a Frisbee 24 hours a day,” said Katherine Ralls, a conservation biologist with the Smithsonian Institution’s National Zoo in Washington, D.C. But as trackers, she said, scat-detecting dogs are a good fit. “They love to do it. They’re happy campers out there.”
For their research on California’s endangered San Joaquin kit fox, Ralls and former University of Washington graduate student Deborah Smith (independent of Wasser’s group) found that detection dogs were unbiased in their sampling and perfect in distinguishing nearly 1,300 kit fox scat samples.
“All were 100 percent accurate. They never made a mistake,” Ralls said, a success certified by extracting telltale mitochondrial DNA from the feces samples and matching it to San Joaquin kit fox-specific DNA.
Although using dogs to track wildlife can be laborious and expensive, Ralls said the technique is especially useful for studying reclusive animals or minimizing contact with endangered species. And for conservation biologists, the scat samples can readily translate into key findings. From the grizzly and black bear feces collected in and around Jasper National Park in the Canadian Rockies, for example, Wasser’s team learned that both species congregate beyond the park in areas altered by human activity.
In the Jasper region, he said, logging is often accompanied by roads edged with clover to prevent erosion.
“It kind of creates a salad bar for the bears,” Wasser said. The clover also provides a temporary food source for bear prey. “The bears in those areas are fatter and they conceive faster, but they are also poached more,” he said. Based on their results, the researchers recommended reducing off-road vehicle access to mitigate the poaching.
From elephant dung to DNA
Amid a booming black market for poached elephant ivory in Asia, Wasser’s team has taken a more high-tech approach to fight the decline of one of Africa’s signature species. Earlier this year, he and collaborators made headlines when they traced 6.5 tons of poached elephant ivory that had been shipped from Malawi and seized in Singapore in 2002 back to the savannas of Zambia.
Elephant dung, weighing up to 25 pounds per pile, may be an easy way to sniff out the animals. But what about tracking the ivory? A crime lab in British Columbia working on extracting DNA from teeth invented a technique that Wasser’s lab has since modified, enabling them to pulverize super-cooled ivory into a fine powder from which DNA can be isolated.
Feces collected from wild elephants allowed his group to develop a genetic map of populations throughout sub-Saharan Africa. By comparing the ivory-derived DNA to the population map, the researchers have deduced the original locations of ivory tusks from multiple seizures. “We wanted to get at the big crime syndicates that are essentially driving this trade right now,” Wasser said. Identifying poaching hot spots and crime strategies can help determine how to concentrate law-enforcement efforts, he said, while identifying the origins of ivory forces countries to take responsibility for elephant-killing within their own borders.
Identifying whale feces can similarly help countries protect their native populations, including an estimated 300 North Atlantic right whales endangered by boat propellers and gill nets in Canada’s Bay of Fundy. Fortunately, the whales’ odoriferous orange feces float and can be readily detected by dogs trained with whale poop in floating Dixie cups. When they’ve sniffed out the scent, the dogs crouch low at the bow of the boat, as if poised to jump in the water. Experienced handlers can then direct the boat captain to angle back and forth to keep the vessel downwind of the scent trail while zeroing in on the source.
For an ongoing collaboration with the New England Aquarium in Boston, Mass., detection dogs have increased the sample numbers five-fold. So far, the whale feces have allowed researchers to distinguish adults from juveniles, males from females, pregnant from non-pregnant females and the mammals’ relative stress levels.
Gator, an Australian cattle dog, and Tucker, a black Labrador retriever, are likewise helping Wasser’s team track orcas in the Pacific Northwest. The orcas, or killer whales, have accumulated the highest levels of the banned industrial compound PCB of any mammal in the world, he said, and have been further impacted by tourism and declining numbers of Chinook salmon. Wasser said later that his group is refining a technique to measure PCB in orca feces along with the ubiquitous flame retardant PBDE, a chemical of concern that he calls “the new kid on the block.”
Alice Whitelaw, a co-founder of the Three Forks, Mont.-based Working Dogs for Conservation Foundation, along with fellow wildlife biologist Deborah Smith, said scientists have yet to fully tap the olfactory capabilities of our canine companions. As to their physical limits, Whitelaw said dogs likely wouldn’t be her first choice for studying cliff-hanging mountain goats, but they’ve nevertheless performed well in Wildlife Conservation Society-commissioned surveys tracking grizzlies, black bears, mountain lions and wolves within the isolated Centennial Mountains along the Montana-Idaho border. Some nesting bird populations likewise may be out of range, though Whitelaw and other biologists believe detection dogs may be good at tracking owl pellets.
Next March or April, Wasser’s dogs may do just that for the Pacific Northwest’s troubled Northern spotted owls and for barred owl invaders from the East. “Hooting” surveys have become unreliable in recent years, he said, because many spotted owls have stopped calling back to avoid drawing attention to themselves with the bigger barred owls on the prowl. Documenting up-to-date spotted owl habitat by tracking their pellets could prove critical for balancing wildlife conservation with timber interests.
The barred owls have become such a threat that some researchers believe modifying timber practices may do little to help their spotted owl prey, but some of Wasser’s early data suggest both the forest conditions and the presence or absence of barred owls matter to spotted owl populations — a hypothesis he hopes his dogs will put to the smell test starting next year.