In the late 1800s, North America was home to some 60 million bison, but during the 19th century they were hunted to near extinction. The reversal of that trend is thanks in large part to ranchers who set out to breed the lumbering creatures for the dinner table.

The success of their venture and growing popularity of bison meat has led to the emergence of massive commercially-owned herds.

John Muggy has been rearing bison on his 35-acre ranch in Fermdale, 170 kilometers north of Seattle for over two decades. The young skip along behind his red pick-up truck as he steers towards his herd which rests in the shade. At the sound of the engine, the animals scramble to their feet sending clouds of dust into the air.

It's only standing that the size of these animals becomes apparent. The cows weigh about five hundred kilos, while the bulls can be more than twice that. But that doesn't faze the rancher. He jumps out of the truck and pats one of the bulls on the back, explaining how he ended up a bison breeder.

Bison can provide many environmental benefits if allowed to roam free

"We wanted something to eat down the pasture," he told DW. "We started with three bison, and were just going to have pets, but a couple of years later we ended up in the retail meat business."

Environmental benefits

His herd of 30 is free to roam at will over his land and the surrounding woodlands, and can drink from the creek that runs through his property. He makes no bones about the role he and other ranchers have played in saving bison from their close call with extinction.

"If we didn't eat them, they wouldn't be here today," he said. "The comeback of the bison—it wasn't our government that did it. It wasn't the navy that saved them on their land or anything."

Hundreds of thousands of the creatures are now kept in commercial herds and an additional 50,000 in conservation herds. Besides serving as a source of food, their patchwork grazing patterns create the ideal habitat for prairie dogs and birds, which is important for the Great Plains ecosystem.

The joy of wallowing

Their love of wallowing also impacts the hydrology of the land where they live. Several times a day, bison drop into the dirt to rub their backs. Because they have razor-sharp bony protrusions along their spines, they can't roll over but have to stand up and flop back down onto their other side.

Bison enjoy a daily wallow

The process generates huge clouds of dust and creates slight dips in the ground which fill when it rains and provide a much needed source of water from certain frog and salamander species.

But as is so often the case in farming, it's becoming increasingly common for ranchers to keep bison in pens and feed them grain instead of allowing them to roam free and graze in an environmentally useful way. And that, says Brent Kim of the Johns Hopkins Center for a Livable Future, is a problem. For many reasons.

"Meat from the feed lot system is going to be associated with much greater harms to public health and the environment," he said. "Problems of resource depletion, food safety concerns, antibiotic resistance, impacts to air and water quality, and even it's a net drain on our food supply."

Eating habits

He urges consumers to check how their meat was raised, particularly in light of its growing popularity in the United States and Canada. Last year four million kilos of bison meat were sold, compared to just one million in 2003. That said, beef is still much more popular, with twelve billion kilos eaten in 2013.

Americans and Canadians are gaining a taste for bison steaks and burgers

The Pike Brewing Company in Seattle has he just added bison burgers to its menu. Chef Gary Marx mixes bacon bits with the ground bison to balance the meat's gamier taste, and serves it on a sweet bun with bacon jam and sautéed onions. It was a risk, but it seems to be going down well.

"Our last menu, which started about a month and a half ago, we wanted something different—not just ground beef," Marx told DW. "And it's selling really, really well. It exceeded my expectations."