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Thinking big
Protecting ecosystems could begin with the restoration of the largest species
by Beth Staples

Martin sizes up shrinking bison
Jeff Martin

Jeff Martin

Jeff Martin’s boyhood interest in fossils was solidified during a family vacation to Wind Cave National Park and The Mammoth Site of Hot Springs in South Dakota.

A stop at Yellowstone National Park in Wyoming that same trip sparked his lasting bond with bison. For Christmas a few years later, Martin’s parents got him Gummy Bear — a 1,700-pound bison.

The University of Maine Ph.D. student in ecology and environmental sciences still has Gummy Bear. She’s the largest female in his 15-member herd and has given birth to 10 offspring.

The vacation inspired Martin’s parents too. They now have 30 bison and during summer months they host as many as 100 more of the magnificent animals with long, shaggy brown coats on the 214-acre family ranch in Wisconsin.

“They’re a majestic and purely intimidating animal and you should have a lot of respect for them,” says Martin about bison, who can weigh as much as 2,200 pounds, run 40 miles an hour and jump 6 feet high.

“If you’re sitting on the ground and they are walking towards you, you can feel every single step shaking the Earth,” he says. “They’re a massive animal — but right now, today, they are the smallest they’ve ever been in their evolutionary history.”

Martin would know.

His childhood fossil and bison hobbies have evolved into academic and career pursuits. At UMaine, he researches how abrupt climate change has influenced bison size.

His goals as a paleoecologist and vertebrate paleontologist dovetail with his goals as a bison rancher — he wants bison and the bison meat industry to flourish.


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Martin is in the National Science Foundation’s Integrative Graduate Education and Research Traineeship (IGERT) program focusing on Adaptation to Abrupt Climate Change (A2C2). IGERT integrates abrupt climate change, economics and ecology.

Bison, says Martin, have existed for about 2.5 million years. And understanding their past is the best way to prepare them for adaptation to future climate change and to inform conservation and economic management of bison.

The deep past is “a natural experiment that has come to conclusion without anthropogenic climate change,” says Martin, whose window into the past is the fossil record of bison.

While many large herbivores — including mammoths, mastodons, giant ground sloths, giant camels and giant moose-elk — went extinct in North America at the end of the last Ice Age, bison survived.

“They’ve covered England to America, Russia to India, Northern Arctic Canada to southern Mexico,” he says. “They’re one of the more successful genera in terms of land coverage.”

On the family ranch in Wisconsin, Martin and his parents utilize holistic (intensive, planned rotational grazing) methods developed by Allan Savory and modified by Joel Salatin. The methods emulate nature and the massive herds from the Sahara and pre-European bison herds of America/Canada.

“We keep them moving between 16 to 20 pastures,” he says. “Production of grasses and bison skyrockets and we stay in the black because of it. I’d like to help other ranchers do the same thing.”

Bison eating

Hucklebeary is a 2,200-pound, 6.5-foot-tall breeder bull on the Martin family ranch in Wisconsin. Bison, says Jeff Martin, are the smallest they’ve ever been in evolutionary history, due, in part, to climate change. The giant bison (Bison latifrons) that lived between 200,000 and 20,000 years ago stood about 8 feet tall and weighed more than 4,400 pounds. Photo courtesy of Jeff Martin

Martin was introduced to the methods when he was an undergraduate at South Dakota School of Mines & Technology and worked at the 777 Ranch. A perk for ranch employees included free courses in holistic management, including intensive, planned, rotational grazing.

Martin believes bison should remain a natural, wild and unregulated species at least until it’s determined how climate change will impact different regions of the country and the bison in them.

In regions of North America that are hotter and drier, bison calves continue to be born smaller. Those in cooler regions in Canada, Montana and South Dakota are larger, he says.

Martin says if bison are regulated like cattle there could be catastrophic consequences. For instance, in the 1970s there was a massive population growth of cattle, which caused overgrazing. When a drought hit the Great Plains, thousands of cattle perished.

And in 2013, tens of thousands of cattle in the Black Hills of South Dakota died during an October blizzard. Bison, Martin says, weren’t affected like cattle. Bison, he says, are four times more resilient to extreme cold weather events.

“We’re going to keep getting [extreme weather] events like that,” says Martin.

Cows and bison have some notable differences. Bison, says Martin, are good for the biodiversity of the landscape.

Their grazing habits tend to increase species diversity. And their wallowing — rolling in the grass to provide relief from heat and insects — makes depressions in exposed soil, which catch rainwater and provide temporary pools for wetland species.

This past summer, Martin was back at Wind Cave National Park in South Dakota. This time, he was with Jim Mead, chair of geosciences at East Tennessee State University, and his adviser Jacquelyn Gill, a UMaine assistant professor of paleoecology and plant ecology.

They all took part in a dig in Persistence Cave. The cave, which measures about 27 feet long and 6 feet deep, with 15 inches of clearance, was discovered after its entrance naturally re-opened due to drought followed by extreme rain events.

The unearthed fossils are those of animals that went extinct and of animals that survived the last Ice Age about 11,000 years ago. Martin wrote about the dig in his blog Bison@Large.

Mead was Martin’s adviser when Martin earned his master’s in geosciences at East Tennessee State University. Martin calls Mead “the No. 1 collector of No. 2,” and says Mead’s collection includes dung from thousands of different species in different seasons.

Martin came to UMaine to work with Gill because of her research linking abundance of the dung fungus Sporormiella to bison population dynamics through time.

Dung allows scientists to understand dietary changes over time and geography, says Martin, adding it helps researchers determine what plants existed at different times in Earth’s history.

Pollen samples from trees and plants also provide vital information about the past climate in North America, including what food was available for bison, as well as for horses, camels and bats around the time of the last Ice Age.

After Martin earns his doctorate, he’ll have considerable quantitative information about bison to share with researchers, policymakers, ranchers, conservationists, tribal groups and the general public.

He looks forward to ranching, working to preserve the majestic animal and enjoying life’s simple pleasures, like the smell of rain in the air right before an afternoon prairie thunderstorm.