I made a comment the other day to someone about what was the greatest natural phenomenon or change of my lifetime. Just like with many other things in the world a lot has changed since the 1950s, so I had to narrow it down to my interests, which would be animals to hunt.
I came up with three things that to this day I am amazed by: the expansion of white-winged doves from a small population in the Lower Rio Grande Valley to populations statewide, the spread of wild pigs or the growth of the Texas white-tailed deer population.
Starting at the bottom, I would bet there are a lot of Texans who do not realize how in peril the state’s deer population was prior to the 1960s. There were a number of factors, but the biggest had to be the screwworm, a fly larvae that was deadly to livestock and wildlife. The short version is that the fly would lay eggs in the wounds of an animal, they would hatch with the larvae causing infection and death if untreated. While individual livestock could be successfully treated, the screwworm problem continued because of wildlife.
After World War II, researchers began working with sterile male flies that would breed with still-productive females ultimately ending the fly cycle. It worked.
Beginning in 1961, millions of the sterile flies were released in Texas. By 1964, screwworm was eradicated in the state. Two years later, it was announced it had been eradicated nationwide.
Prior to the 1960s, Texas had less than a million deer statewide. In 1961, the number climbed to 2 million and by 1965, it was 2.25 million, according to the Texas Parks and Wildlife Department. Today, because of the eradication of screwworm, transplanting efforts through the years and conservation, the number is 3-million-plus and growing.
Unlike white-tailed deer, everyone knows the story of wild pigs. They showed up with French explorers in the 1680s, hung around virtually unnoticed for 300 years and then seemingly overnight were found in every county in the state.
Like white-tailed deer, wild pigs also got a helping hand expanding around the state, but by hunters and not biology. Based on the financial damage caused to farmland and landscapes, along with the problems they cause for livestock and other wildlife, wild pigs may go down as one of the largest human errors of its kind ever in Texas. Ironically, at this time screwworms might be the only thing that could truly slow them down.
The jury is still out on the impact of white-winged dove expansion across the state, but to me it is the most interesting of the three. In the early 1900s, whitewings existed primarily in the four southern-most counties in Texas. Irrigation and farming saw their numbers rise to more than 3 million in the 1940s, before a hard freeze in the early 1950s killed much of the citrus industry in the Lower Rio Grande Valley and the birds’ numbers plummeted. At one point there were maybe 200,000 whitewings remaining, and hunting for them was closed in 1985.
However, as the numbers in the Valley were tanking, the doves began expanding their range and before long there were more in San Antonio than there were in South Texas. Today, TPWD estimates there are between 10 and 12 million of the birds statewide, and that only about a quarter of them live in southern Texas south of a line running from Del Rio to Orange.
“We estimate that about 80 percent of the current population is associated with urban areas. They are now found in just about every county in Texas, though the Pineywoods ecosystem is the least populated,” said Owen Fitzsimmons, TPWD’s dove program leader. “They’re expanding beyond our borders, as well, moving into Oklahoma, southern Kansas, northern New Mexico, Colorado and southern Louisiana. There are even reports in recent years of individual birds sighted as far north as southern Canada.”
Fitzsimmons said the trees of urban settings create ideal nesting habitat for the dove. From there they feed at backyard feeders or migrate daily into nearby agricultural fields. They have been in Tyler for at least five years and the numbers are slowly growing. I had my first mating pair coming to a feeder this spring.
Biologists have found that while the original South Texas population of whitewings was migratory like mourning doves are, the new more-urban population does not seem to be.
“They seem to be thriving, which I suppose shouldn’t be surprising given that doves and pigeons around the world seem to adapt well to humans, but we don’t have much detailed information about the annual ecology of these more urban birds,” Fitzsimmons explained.
With the whitewings’ expansion statewide, it is not surprising more are showing up in hunters’ bags. TPWD surveys showed about 30 percent of the 7- to 10-million annual statewide harvest is now whitewings.