Cattle rancher Johnny Mestas doesn’t want to get too worked up about New World screwworm , a fly whose parasitic larvae can eat cattle alive. The 74-year-old says he’s already had two heart attacks over the long course of his career farming in the parched San Luis Valley of southern Colorado.
“Not everybody is meant to be a farmer,” said Mestas. “You’ve got to be half-crazy. There’s three elements you fight: the market, the weather and your neighbors.”
Half-crazy or not, Mestas is uneasy about a new development in the ongoing saga of the screwworm: the US government’s plan to reopen part of the southern border to Mexican livestock on Monday.
To prevent the spread of screwworm, the cattle trade with Mexico has been shuttered on and off since November 2024, with the current border closure put in place in July 2025. But next week, the border will reopen in Douglas, Arizona for cattle from Sonora, Mexico.
The issue has reanimated a decades-old debate over protectionism within the cattle industry. Several US cattle producers say they are being pitted against Mexican ranchers and American meatpackers amid soaring beef prices for US consumers.
Mexican producers are optimistic that the border reopening might staunch over a year of financial bleeding. Alvaro Bustillos, the head of the rancher’s union in the Mexican state of Chihuahua, hopes that a successful reopening in Sonora might lead to renewed cross-border trade with his region. The border closure nearly killed his business.
“I had to fire people,” Bustillos told CNN. “It took me years to build my team. It took me years to build relationships. This is not only about the cattle trade. This is about families bonded together.”
But US ranchers warn that they’re bleeding, too. One of the loudest voices in the cattle world agitating against the border reopening is Bill Bullard, the CEO of R-CALF, a national association of independent cattle and sheep farmers. Bullard, a former rancher from South Dakota, speaks about screwworm as one element of a broader crisis facing American ranchers: namely, an influx of less expensive cattle and beef from Mexico.
“In just over a generation’s time, we wiped out half (of) our cattle producers in this country,” said Bullard in an interview with CNN. “It’s because we have been growing our dependence on foreign sources, displacing our domestic production in the United States. It is a threat to national security.”
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US officials had chosen to open the border at Sonora due to the state’s high industry standards and its lack of screwworm cases. Yet just days before, Sonora reported its first screwworm infestation , though the single case doesn’t appear to have slowed the US Department of Agriculture’s plans. The agency said Thursday that it intends to move ahead with the reopening.
Even before Sonora reported its first case, many American ranchers like Mestas have been skittish about reopening the border, and not just because they worry screwworm could hitch a ride on Mexican cattle.
US ranchers who don’t rely on Mexican cattle worry that bringing foreign livestock into the country could lower cattle prices, currently at historic highs . American consumers have been struggling with soaring beef prices for over two years now, but the elevated cost of livestock has been a relief for those ranchers, who feel they’re finally being paid fairly for their work.
“These past few years, I actually made money!” Mestas said, with an audible hint of amazement. “Years and years, it was basically always break-even.”
Beef prices, along with the broader cost of living, are also a salient political issue ahead of the 2026 midterms. Jenna Stanton, director of policy with the US Cattlemen’s Association (USCA), told CNN that many ranchers see the Trump administration’s push to open the border as an attempt to ease market pressures and lower the cost of beef.
The White House had previously angered US ranchers by quadrupling low-tariff imports of Argentine beef to cool prices. On Friday, the president announced that the US would import 300,000 metric tons of beef to “reduce prices for Americans while giving space for our Great American Beef Herd to grow again.” The decision quickly drew criticism from cattle industry organizations .
“There’s a midterm to be won this fall that, frankly, they are losing,” said Stanton. “They are looking to pull any lever they can.”
CNN asked USDA about whether beef prices and the upcoming midterm elections had any bearing on the decision to reopen the Douglas port. The agency responded by sending CNN an op-ed by Agriculture Secretary Brooke Rollins that mentioned neither the elections nor beef prices.
“If at any point we determine there is an imminent threat to our domestic herd, we will not hesitate to immediately pause the reopenings,” Rollins wrote. “Protecting American livestock will always come first, and we will continue using every tool at our disposal to support the ranchers who raise them and to eliminate (screwworm) once and for all.”
Cries for economic protectionism by some ranchers and crises of animal health like screwworm often go hand-in-hand, according to agricultural historian Bill Winders of Georgia Tech. Bullard’s organization R-CALF similarly argued for a border closure with Canada during an outbreak of mad cow disease, a fatal brain-destroying condition, among Canadian livestock in the early 2000s. That closure lasted over two years.
“These kinds of moments are often seized upon by organizations interested in protectionism,” said Winders. “And it can often help their position, even if just in the short term.”
Winders notes that R-CALF only represents one part of the larger cattle supply chain. Numerous other agricultural organizations are in favor of the phased reopening, such as the National Cattlemen’s Beef Association (NCBA), a trade association for ranchers and feeders, including many who rely on Mexican livestock.
The NCBA didn’t respond to multiple CNN requests for comment, but said in a statement posted online that the border reopening will “help normalize business for cattle operations throughout the border states and Southern Plains.”
Derrell Peel, a professor of agricultural economics at Oklahoma State University, is skeptical of R-CALF’s narrative about the benefits of border closures for the US cattle industry. Peel, who is an expert on the Mexican cattle trade, told CNN that screwworm isn’t the primary force behind high cattle prices, and sees the issue as a fig-leaf for a broader anti-free trade agenda.
The high prices are due to the US cattle herd – the total population of cattle and calves in the US – being at a 75 year low after years of frequent, severe droughts, he said.
That lack of supply, not just the screwworm, has pushed prices up. “We would have had record cattle prices (in the US) with or without the border closed,” Peel said.
In the meantime, Peel added, Mexican ranchers have lost up to a thousand dollars per animal since the border closed to the livestock trade.
One of those ranchers is Bustillos, the union head in Chihuahua, who declined to put a dollar figure on the money he’s lost to the border closure.
“I lost a bunch of money,” Bustillos said. Closing the border to the cattle trade “destroyed the dynamics of the market.”
He also worries about his colleagues in the US meatpacking industry, many of whom relied on Mexican exports to make their bottom line. Cattle that might have come to the US and fattened on American corn to be turned into steaks are now fed, slaughtered and packed entirely in Mexico – then sent to the US as boxed beef. According to USDA data, Mexico has exported 22% more boxed beef to the US this year.
US meatpackers are responding with cutbacks. Last week, major meatpacking company Tyson Foods announced it is closing plants in Illinois and Utah and seeking to sell a facility in Washington, citing “one of the most historic cattle shortages the country has ever experienced.”
“These cattle (in Mexico) had to go somewhere,” Bustillos said, “What the US doesn’t understand is they’re going to give all that leverage to Mexico as an industry.”
Mexico has built out its ability to export beef significantly over the years, said Peel. He warns that the border closure’s disruption could last a long time.
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“The fact that (Mexico is now) absorbing those exportable cattle that they have not been exporting will probably lead to changes in the supply chain,” said Peel, “It might become more permanent in nature.”
As for the animal health risk, many proponents point out that screwworm made it into the US either through infested wildlife or via flies themselves while the border was closed to the cattle trade.
Sam Garcia, a Mexican American rancher and scientist who raises cattle in Sonora, told CNN that any livestock entering the US will be inspected numerous times for screwworm before being dipped in a chemical bath.
While expensive cattle may have given some American cattle producers breathing room, ranchers who spoke with CNN emphasized that high prices haven’t ensured easy wealth. Ranching is still difficult and often unprofitable work, especially for family operations.
“Can we stop the bleed of the American rancher?” asks Cooper Little, the director of the Independent Cattleman’s Association of Texas.
It’s a question he says he often poses when speaking with the thousands of small cattle ranchers in his organization, many of whom are elderly and struggling to stay afloat despite better revenue from high prices.
Little, who speaks with an unmistakable Texas twang, saw the border closure as a chance to reshore the US cattle industry and stop the bleed. Without competition from Mexican producers, people might “have an interest in entering the beef cattle industry and being the legacy of their father or grandfather.”
“It’s a hard life,” Little says of ranching. “And it’s getting harder every year.”
J Storme Birdwell, who runs her family’s ranch on the Texas Gulf Coast, says day-to-day cattle production is a struggle.
As expensive as cattle are, land is worth more . In recent years, Birdwell says she’s had trouble retaining leased plots of pastureland as younger generations of ranching families choose to cash out and sell rather than stay in the harsh world of agriculture.
Those struggles are also intimately familiar to Mexican ranchers. Garcia, the Mexican American who raises cattle in Sonora, emphasizes that US and Mexican cattle producers are more similar than they are different, despite competing interests.
“I can tell you,” Garcia said. “I have more in common with an American rancher than a politician in New York.”
“The difference is labor might be cheaper down in Mexico, but also there’s not that many government incentives to be more productive” compared to the US, he said.
Another of those shared issues is the lack of water. Ten years ago, Johnny Mestas in Colorado says he nearly lost his herd due to an expensive fight over water rights. Drought is an insidious threat to ranching life, and it’s only getting worse with climate change.
“Some of my neighbors think I’m one rich sucker,” Mestas said, “But they don’t know half the sh–t we went through.”
