Biologists spot rare black mule deer in Texas, video show
A team of biologists have spotted a “one in a million anomaly” in the West Texas desert, according to state wildlife officials.
It’s not easy to see at first, rushing and leaping up a shadowy mountainside, but as the biologists close in on a helicopter, their camera captures brief but clear evidence.
“The rarest of the rare“, said the Texas Department of Parks and Wildlife in a March 29 Facebook post, sharing the video.
Mule deer are a standard sight in the vast Trans-Pecos Regioncommonplace among brush and cacti — but not this one, TPWD said.
This special deer appears all black except for quick flashes of white fur as it flies away from the whirring helicopter. It contrasts sharply with the older, larger mule deer that precedes it, sporting the typical brown and white coloring.
The fawn has melanism, experts say, a unique condition that can occur throughout the animal kingdom, resulting in darker fur, hair or skin.
Or as TPWD puts it, melanism is “a rare random genetic abnormality believed to be caused by mutations in the melanicortin 1 receptor (MC1R) gene that leads to overproduction of the pigment melanin.”
Experts don’t know how rare melanism is in mule deer, “but it’s estimated to be around 1 in several million,” the post read, making these deer rarer than mule deer. albinos or the spotted-patterned piebalds.
Melanism can be advantageous in nature, according to TPWD.
The “additional pigmentation protects [animals] from sun exposure and increases their ability to absorb heat in cold weather. The darker coloring also allows animals that are active at night to hide more easily.