Discovery of bones in Duval County mostly are from the Pleistocene age, a more recent geologic time going back 10,000 to 1.8 million years. While officials of the United States National Museum could not identify large fragments of bone found 2.5 miles north of Concepcion in gravel and sand deposits on the Agua Poquita Creek, they determined that the bones were likely from the Pleistocene age. Bone fragments from the time were also found on Agua Poquita where it intersects the Benavides-Concepcion Road, on the Concepcion Creek near Concepcion, and on a number of other creeks in the county. A. L. Labbe found a 3-foot tusk in a well on the Labbe ranch along the banks of the San Diego Creek. Other Pleistocene era fossils were found on the San Diego Creek, 1.5 miles east of San Diego.
It was at the close of the Ice Age that humans might have made their first appearance in Duval County. Anthropologist Thomas R. Hester observed in his book Digging Into South Texas Prehistory, “There are several localities in south Texas with evidence of habitation attributed to a time prior to 11,000 years ago…there were claims some decades ago for the association of artifacts and mid-Ice Age fossils in the so-called ‘equus beds’ of Duval County…”. This would place humans in Duval County during the earliest known times of human existence in North America. At this time, grass and forests covered South Texas and Duval County where mammoth, mastodon, and other extinct animals roamed freely. Later, grass vegetation covered the area. Rivers and creeks flowed year-round and smaller wild animals such as buffalo, pronghorn deer, antelope, bear, and prairie chicken abounded. While not extinct, none of these species are found any longer in Duval County.
Of course, without the ability to write, we know very little about the earliest inhabitants of Duval County. What little we know comes from geologists, anthropologists, and archeologists digging around South Texas for water, oil, gas, and uranium. The evidence from these digs indicate that native Duval County people were hunters and gatherers that, unlike later inhabitants, did not practice agriculture or raise animals, and did not organize into clans or communities.
Perhaps the earliest incursion into the Duval County area by a European was in 1533, less than 50 years after Columbus discovered the New World. According to Bethel Coopwood, Cabeza de Vaca traveled in the area of Duval County while he was making his way from Florida to Mexico. It should be noted that Coopwood’s theory is one of a number routes attributed to De Vaca’s, including others that do not bring him to Duval County. Assuming Coopwood is correct, De Vaca landed in St. Joseph’s Island off the coast of present-day Corpus Christi.
After Indians captured De Vaca, he escaped and wandered in the wilderness for years before reaching Mexico. He made his way to an area where McMullen and Duval counties meet. It was an area where the prickly pear was abundant, which De Vaca wrote was very popular with the Indians. De Vaca identified 17 Indian tribes who lived in villages and spoke different tongues. It is not clear which ones inhabited the Duval County area but when De Vaca was supposedly in Duval County he was traveling with the Avavares tribe.
From the McMullen County line, De Vaca and his Indian friends marched some 60 miles over a large expanse of flat dry land to a stream where they found an ebony scrub that bore fruit similar to an English pea. The stream, Coopwood surmises, was the Agua Poquita in the Concepcion region of the county. The fruit described Coopwood believes was the maguacates, which were plentiful in the area. From there De Vaca traveled to the Rio Grande River in Zapata County over “dense jungles and prickly pear thickets, where the thorns” reminded De Vaca of the crown of thorns worn by the Savior.”