Melanistic Whitetails: How One State Dominates the Whole Population

Across North America, nearly all white-tailed deer could be described as perfectly normal. No matter how big or small they are, their general appearance fits the species standard. They’re just deer.

On rare occasion, though, nature throws us curveballs. “Cactus” bucks that never lose their velvet. Antlered does. Bucks with canine teeth. And animals of either sex displaying more than the usual amount of white: some with only a few extra splotches, others with an entire coat like snow.

But one other sort of “freak” stands out as the rarest of all. It’s a whitetail whose coat is solid black, or at least so abnormally dark as to give that impression. There are usually no white markings on the head, throat, lower legs or belly, only on the underside of that namesake tail.

This genetically controlled trait is called melanism, as it results from an overload of the hair, skin and retina pigment melanin. While not limited to whitetails — it’s also been documented in many other mammals, plus birds, reptiles and even fishes — it’s so rarely seen in the deer herd as to be totally unknown to most hunters.

To show just how rare melanism is, consider that across most of North America, there are zero historical records of a black whitetail having been observed or shot. Since the 1940s, in widely scattered parts of the Great Lakes region and later in a few other places there have been only a relative handful of reports. What’s more, they show no obvious pattern of occurrence.

It’s different in one specific part of Texas, however. There you’ll find far more melanistic whitetails than have been documented in all other places combined. It makes for one of the more interesting oddities in the deer world.

BLACK FAWN OF THE FAMILY

When hunters and landowners speak of whitetail genetics, nearly always the focus is on antlers. It’s widely understood that certain genes affect the potential size and details of a buck’s headgear. But there’s much more lurking in the herd’s DNA, including control of hair color.

A melanistic whitetail is just another take on the old idiom, “black sheep of the family.” Whether in sheep or deer, a black coat is due to the gene controlling hair color causing the animal to produce far too much of the melanin type called eumelanin.

But even when the mutated gene responsible for this trait is present, it’s recessive. Without its presence in both parents’ DNA, there’s zero chance that they’ll produce dark offspring. Only if both parents actually display melanism is there a guarantee that the fawns will also be abnormally dark. Otherwise, whether both parents are normal in color or one is melanistic, the chances of having dark fawns are reduced.

Also, when melanism shows up, it can be at various levels, from coal black to smutty gray-brown and various shades in between. This results in some deer that fully fit the melanistic profile, while the remainder could be described as semi-melanistic.

For an everyday parallel, look at humans. Not all natural redheads have identical hair color; the spectrum runs from light strawberry blonde to rich auburn. These variations are due to a given redhead’s inherited genetic blueprint, possibly also influenced by hormonal and environmental factors.

Variations in melanistic whitetails likely have similar causes. Yes, the right gene abnormality must be present in both the mother and father, but it’s difficult to say how other factors might come into play. Nature is hardly a controlled experiment.

In a few cases, only certain parts of a whitetail’s coat are melanistic. Examples would include a black body and head with normal white eye rings and muzzle markings. A deer with a black head/face but an otherwise normal coat is another rare variation. Scientists refer to this trait as pseudomelanism.

Not only do melanistic deer vary in how dark they are, their age and the time of observation can affect their appearance. Many dark fawns start out with faint white/gray spots before losing them. Texas photographer Jared Markgraf, whose images accompany this text, notes that melanistics’ summer coats often are brownish black, but then blacker in winter. They’re especially hard to see in low light and/or shadowy cover.

THE EPICENTER OF MELANISM

In wild whitetails, dark deer are most often observed in a narrow band running from a few miles north of Austin, Texas, to the northernmost suburbs of San Antonio. This zone stretches 100 miles or so north to south and 60 miles west to east along a northeast-to-southwest line. Within it are nine contiguous counties: Travis (Austin), Hays, Comal, Guadalupe, Caldwell, Blanco, Williamson, Burnet and Bexar (San Antonio).

The area includes a section of the Balcones Escarpment, the sharp boundary separating the dry, rocky Edwards Plateau to the west and the more fertile Blackland Prairie to the east. The southern tip of the Cross Timbers ecological region brushes against the northern edge of the zone, which is bisected by Interstate 35. Dark deer live on each side of that highway, but most are along river and creek bottoms in the western section, close to the escarpment.

Because Texas has long been at the forefront of intensive whitetail management and even selective breeding of captive deer, might melanism there have begun with human manipulation? It’s impossible to be sure.

The state’s earliest reported sighting of a black whitetail in Texas was sometime around World War II. The old Game, Fish & Oyster Commission’s restocking efforts had begun in 1938, to boost populations in many locations. But all those stockings were of animals from elsewhere within the state, and to date no known pocket of melanism has been found where any of those founding deer originated.

Nor is there proof high-fenced properties had an influence. Nearly all the dark deer live outside such enclosures. A fair percentage are in unhunted parks, greenbelts and suburban neighborhoods, likely boosting their survival, but many also are on hunted land in the area. With it being legal to shoot melanistic deer during state bow and gun seasons, some are tagged every year.

DOCUMENTING THE ODDITY

The most serious research into the state’s melanistic deer was spearheaded by now-retired university professor Dr. John Baccus at Southwest Texas State University (since renamed Texas State University). Starting in 1988, Dr. Baccus and associate John Posey conducted a lengthy study of the phenomenon. The university's location in the Hays County seat of San Marcos proved ideal for such a study, as many of the dark deer were believed to be within an hour’s drive of campus.

Estimating the population involved roaming the area, investigating known pockets of melanism and following up on new leads from landowners, hunters and taxidermists. Trail cameras weren’t yet available, so visual confirmation of live deer was a key part of the work. That meant a lot of driving back roads, walking specific transect lines across the land and even sitting in blinds.

Over time, the researchers pieced together a map of where the deer were and at what population levels. And the results were impressive: 225 melanistic or semi-melanistic deer among their total 3,875 whitetail sightings.

The greatest concentration of dark deer was in an area including eastern Hays and western Travis counties, or generally west and southwest of Austin. A whopping 21 percent of all melanistics found in the study were documented there. Overall, 8.5 percent of the deer seen on the study area’s 11 census lines were recorded as being abnormally dark.

It’s interesting that observations quickly tapered to zero farther west of this epicenter. The habitat looks the same. But I don’t doubt the researchers’ findings, because they match my own. I grew up on my family’s cattle ranch in Blanco County, a location under 25 miles west of the highest density of melanistic animals found in the study — and yet no one I know has ever see one on or near our land.

What’s more, from 1959-99 my family owned a meat plant a few miles north of our ranch and processed great numbers of whitetails for area hunters. Despite taking in perhaps 35,000 deer in that span, we never received an abnormally dark one to process. The zone of melanism simply doesn’t appear to extend that far west, despite a continuation of similar habitat and high densities of normally colored deer.

WHAT’S THEIR FUTURE?

It’s been a third of a century since the Texas study was done, and in that span the human population of the area has roughly tripled. Many large family ranches have been sold and subdivided, resulting in far more homes and highways and more fragmented habitat. This of course brings up the question of whether the area’s dark deer might one day vanish.

That doesn’t appear to be a concern. In fact, anecdotal evidence suggests numbers might be on the rise. Landowners in some parts of the melanistic zone report seeing more of them than ever. And Jared Markgraf, who spent several years chasing down leads on dark deer before ever managing to capture images of one, says he now has found some a bit south of where the researchers did.

IN CONCLUSION

No one knows if the conditions that caused melanism to arise and flourish in one part of Texas still exist. However, it’s clear the trait has found a home there. The dense juniper thickets and live oak mottes lining local waterways apparently suit these whitetails, even in the face of rapid human expansion. With overall deer densities still high, and with melanistic genes now well established in the herd, there’s no reason to think this curiosity will go away any time soon.

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