Using an animal's DNA left behind in their natural habitat is an ethical way ecologists and conservation officials can keep tabs on animals, say researchers in a new study.

A team from the University of British Columbia Okanagan and the University of Alberta has released an article that says genetic tagging – or using DNA such as saliva, hair and feces – can provide researchers with an abundance of data. 

Not only that, but they say using DNA is less invasive than ear tags and collars. 

"This research was motivated by a recognition that this way of doing ecology is really taking on an important role," said Adam Ford, assistant professor in biology at UBCO and Canada research chair in wildlife restoration ecology in a news release. 

"Not only is it cost-effective and logistically feasible, but it checks a lot of the 'science' boxes we need to conserve wildlife."

In its research, the team travelled to B.C.'s East Kootenay region and collected the DNA of grizzly bears. They then used this to identify each animal and create unique detection histories, which has allowed them to create density maps and detect population trends or migrations. 

That doesn't mean tags and collars aren't useful in some cases, however. 

"Tags work well, particularly for smaller mammals, but you have to capture the animal first, and then somehow recapture it—and do this in a way that's safe for you and them," Ford said. 

"GPS collars are linked to satellites so we know the animal's location, but again, you have to capture the animal. These collars can cost a couple thousand dollars each and we wouldn’t have the funds to use these in a large study."

Even so, genetic tagging is more ideal for some animals such as bears. They scratch their backs on trees, which offers a lot of insight. 

"We can identify these rub trees because many bears will rub on the same one—we believe it's a communication method," Ford said. 

"We can collect bear hair left on the bark, or on wire that pulls hair off the animal. We return to the tree every three weeks, send the hair to the lab and we know who’s in the area."

Ford said he hopes genetic tracking will help ecologists understand why animal populations are changing and what can be done. 

"I want people to know how much information you can get in a less invasive manner," he said. 

"It's part of our ethical obligation to conduct research in a way that causes the least amount of harm. This tool is helping us get there."