Bison field research 2

Wildlife in Theodore Roosevelt National Park (South Unit) in July 1999
(Photos by Aleen Kienholz) Click on any photo to see a larger version

Bison herd grazing on the Mike Auney prairie
dog town near the Little Missouri River

Bully for Teddy! It's very fitting that this national park should be named for President Roosevelt. He's the man who pushed for the creation of our national park system and the protection of America's wild lands for future generations. He loved this countryside. He hunted bison here as a young man (1883) and also tried his hand at cattle ranching in the prairie badlands before he became president. He witnessed the depletion of the area's wildlife and the degradation of the grassland due to overgrazing by livestock.

This area gained memorial national park status in 1947 and was redesignated as a national park in 1978. The current boundaries encompass over 70,000 acres. It is currently estimated that the park's wildlife populations include 330 bison, 130 wild horses, and 400 elk.

Mare and foal on Halliday Well
dog town

Paint stallion from 3-horse
bachelor herd

Prairie dogs form large communities or "towns" covering many acres: there's safety in numbers. These rodents contruct elaborate burrow systems with multiple entrances and keep vegetation eaten down around them. Family groups defend their territory against neighboring dogs. Coyotes, badgers and eagles prey on prairie dogs. The mound at the burrow entrance is a good place for sentry duty. A warning bark sends nearby dogs running for cover. (Endangered species? Considered vermin by ranchers, prairie dogs have been widely exterminated over much of their former range.)

Roly-poly prairie dog near its
burrow: it won't venture far from
this safe haven.

Black-tailed prairie dog

"Do I need to be afraid of you?"

Bison cow and calf

Bison are in the same group of mammals as domestic cattle, sheep and goats. Both sexes have "beards" and have true horns that are not shed. (Deer, in contrast, have antlers.) Adult bison weigh 800 to 2,000 pounds, with bulls being substantially larger than cows. The head is massive and there is a high hump on the shoulders. The fur is dark brown, and it is long and shaggy on the head, shoulders and front legs.

Two bellowing bulls

Most bison calves are born in May after a nine month gestation period. Cows usually produce a single calf. The breeding season, when cows go into heat and bulls display rutting behavior, is at its peak in late July and early August. The bellow of a bull bison is almost like the roar of a lion. These big animals are potentially dangerous at any time of year and are especially aggressive when competing for females.

When a bull bellows, his tongue sticks out. He's not panting.	Cow and bull (behind) walking parallel to each other. Note how much taller he is at the shoulder
Bison calf with reddish-brown fur (note the little horns)	Bulls, cows and calves resting in the midday heat on the Peaceful Valley prairie dog town)

Many of the aggressive or reproductive behaviors of bull bison during the breeding season are illustrated in the following photographs. A bull sniffs or licks the genitals or urine of a cow to detect the pheromones (sexual chemical signals) that indicate whether or not she is ready to accept a mate. (This is common in MANY species, from elephants to shrews.) She is only "in the mood" for a few hours, so timing is important. He has plenty of competition for the right to be her mate. If an impressive display of power and dominance isn't enough to discourage rival suitors, fights occur. Some bulls never get the chance to mate.

Bull sniffing a cow	Lip curl (helps him pick up her scent)
Tearing up the ground with the horns (bulls also "fight" with shrubs)	Pawing and urinating (note the scars on his back from previous battles)

Wallowing really stirs up the dust, but a good scratch feels great!	What must the poor little prairie dogs think of having these big beasts in their midst?
When white settlers first started moving west, there were millions of bison migrating throughout the great plains. By the late 1800's, overhunting had pushed them to the brink of extinction. Now there are thousands of bison in isolated pockets on federal, state and private lands. It's fortunate that we didn't lose these magnificent, shaggy beasts forever.

The topography of the North Dakota badlands has been shaped by erosion for thousands of years and still changes a bit every time it rains. The hills and plateaus are cut by a maze of gorges and canyons. Trying to cross through this country in a wagon or even on horseback must have been a formidable undertaking. Hence the name... badlands. Below: two vistas from the park's south unit.

Wild horse country

Moonrise near Wind Canyon

THE END of this tale
(and the end with the tail)

Theodore Roosevelt National Park and the historic town of Medora are well worth a visit. If you'd like to learn more, click on the park's logo below, and that will take you to their web site. Just remember to pay attention to the signs in the park...BUFFALO ARE DANGEROUS!

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Updated by Aleen Kienholz on 8 June 2003