the wisent isn’t extinct…completely

The Wisent, or European bison, is a look-alike of the American bison, but its genetics tell a different story.

Wisent, European forest bison

Wisent, European forest bison, is really a grassland animal that takes refuge in the forest.

As the story goes, once upon a time between ice ages, steppe bison wandered the grasslands of Europe, Asia, and North America, traversing the Bering land bridge during glaciated times.  Cut off from Asia when sea levels rose, the steppe bison in North America underwent moderate changes to become the buffalo we recognize today, but then suffered huge declines in numbers when railroads through the central plains brought hunters that killed off huge numbers of them.

American bison

American bison in Wyoming

The steppe bison was also hunted extensively, and may have gone extinct from overhunting about 11,000 years ago.  But aurochs (European progenitor of cattle) and Steppe bison matings in Europe produced hybrids (now known as Wisent) that survived the hunting pressure, perhaps by retreating deep into the primeval forest.
European bison, Wisent

Wisent numbers also declined precipitously with settlement and expansion of agriculture in Europe, but a few remained in the small forest fragments, like the one near Bielowieza.

European bison, Wisent

Hybrids usually are less fit than their ancestors, largely because they are less fertile (e.g., mules), but in the case of the European bison hybrid, they appear to have survived both hunting pressure and the extreme cold of the interglacial periods better than their steppe bison ancestors, and retreated to the forest for protection.

How do we know this?  A fascinating study compared animals in cave art paintings with DNA fragments from bison remains of 15-50,000 years ago and found transitions in the DNA that coincided with animals represented in the cave art.  The animals represented during the coldest periods were the short horned, less humped at the shoulder, Wisent.**

Bison reserve, Bielowieza, Poland

The Bison reserve near Bielowieza has expansive enclosures for its animals, and lots of natural prairie grass for forage.

Captive breeding of Wisent at the Bison reserve just outside Bielowieza attempts to track genetic ancestry and propagate animals that could be released to the wild, but wild Wisent exist in small herds through the forest-grassland spaces in eastern Poland.  They are mighty hard to spot — judging from our early morning explorations of the area.

Bison reserve, Bielowieza, Poland

Bison reserve, Bielowieza, Poland

**http://www.nature.com/news/mysterious-origin-of-european-bison-revealed-using-dna-and-cave-art-1.20822

Buffalo — up close

Our first stop on this cross-country adventure was Cross Ranch in central North Dakota, a 5600 acre Nature Conservancy preserve.  Originally a large cattle ranch, this landscape of rolling hills and flat valley grasslands is being used to raise about 250 buffalo, along with supporting a diversity of prairie plants and animals. Bison at Cross Ranch, Washburn, North Dakota We saw Sage Grouse, a coyote, and an assortment of songbirds, but we came to see the big bruisers that cruise the ridge lines looking for the sweetest new sprouts to munch. I thought seeing a big herd from a distance was a thrill, but wasn’t prepared to meet them from just a few feet away, as our intrepid tour guide maneuvered his 4-wheel drive right up next to the herd. Hardly needed a telephoto for these shots. Bison at Cross Ranch, Washburn. North Dakota As is the case for many species of hoofed animals, buffalo females and their offspring (males only up to 2-3 yrs of age) make up the herd. Bulls hang out alone or in small stag groups and only join the herd during the rut, once a year. These calves were only about 2 months old. Bison at Cross Ranch, Washburn, North Dakota That’s not a brand on this female’s back — those are scars left by the feet of the male when he mounts her. Bison at Cross Ranch. Washburn, North Dakota They shed their heavy winter coat from the rear forward, but retain the dense fur around the neck and head into the summer, making them look even larger.