Excerpts from Jim Conrad's
Naturalist Newsletter
from the April 14, 2013 Newsletter issued from the Frio Canyon Nature Education Center in northern Uvalde County, southwestern Texas, on the southern border of the Edwards Plateau; elevation ~1750m (~5750 ft); N29.62°, W99.86°; USA
FERAL HOGS
In an open bottomland woods along the little Dry Frio River just south of here I spooked some black hogs rooting beneath the live oaks. That's them below.
Feral hogs are a big deal here, though you seldom see them in broad daylight like this. Mostly they're nocturnal; our wildlife camera strapped to a tree has photographed them walking down trails at night. Often you find spots where they've rooted up car-sized or even house-sized areas, and sometimes those spots are so gravelly or packed with cobblestones that you wonder how any animal with a fleshy nose could turn up the soil like that. Some wildlife experts say that, after the deer, feral hogs are our second-most abundant large, free-living animal.
The Texas Department of Agriculture estimates that Texas is home to nearly 2.6 million feral hogs; the Texas AgriLife Extension Service estimates that statewide annual economic damage caused by feral hogs is 500 million dollars. It's worth noting that North America's ecosystems did not evolve with wild swine rooting up the soil.
Feral hogs are swine that either at one time were released or got away and now are "wild," or, more commonly, they're the descendants of such hogs. But when you see feral hogs in the wild they're so edgy and streamlined looking, and usually colored black, that it's hard to believe they're just wild farm hogs or their descendants. Sometimes feral hogs are called Razorbacks.
At least around here several large ranches in the area have imported Russian Boars for commercial hunting, and the boars have mated with our feral hogs. That's possible because Russian Boars and feral hogs are the same species. The European Wild Boar, SUS SCROFA, of which the black to dark gray Russian Boar is a race, is the ancestor of the domestic pig, from which our feral hogs derive. In fact, pure-breed Russian Boars have virtually disappeared due to interbreeding with domestic hogs.
But, in our area, the issue is even more interesting. That's because here in southwestern Texas it's also possible to see pig-like Javelinas, also known as Collared Peccaries. A map showing the Javelina's distribution in the US -- demonstrating that in southern Uvalde County with its scrubby, semi-desert vegetation more than ten Javelinas or peccaries per square mile can be expected-- is at http://www.javelinahunter.com/images/bigpigmap.jpg.
Javelinas are streamlined, darkish critters known to the scientific world as Pecari tajacu. With that name you see that not only are they a different species, but also they belong to a different genus. In fact, they're also members of an entirely different family -- not in the Pig Family, the Suidae. They belong to the Tayassuidae, which means that Javelinas can't really be called pigs. The Tayassuidae is the Peccary Family, so javelinas or peccaries aren't pigs, they're their own thing: They're peccaries.
So, how do we know that our picture shows a feral hog and not a javelina? Anyone familiar with both recognizes the difference immediately. The Javelina's body sharpens into a funnel-shaped head with little detectable neck. Also, javelinas are smaller than hogs, bear unnoticeable tails, have only one dew claw on the hind foot, a scent gland near the base of their tail, a grizzled-grayish coat with a white band of hair around the shoulder or "collar," and are more social than hogs.
The insets at the top of our hog picture clearly show that these animals have distinct tails. At a distance, the amateur naturalist can look for that tail. Javelinas tails are just little nubs.