Humane Borders: 4,505 Arizona desert migrant deaths over 25 years
The Pima County medical examiner’s office reported that the remains of 19 migrants, including children, were recovered along the Arizona-Mexico border in July—the highest monthly total in that area since 2024. The figure brings total remains recovered in Pima County this year to 73, 14 more than the same period in 2025, according to county data.
According to Humane Borders, a nonprofit that helps rescue migrants from dehydration and exposure and works alongside Pima County to track deaths, at least 4,505 migrants have died in the Arizona desert over the last 25 years—an average of roughly one every other day. The most frequent causes of death, according to the group, are dehydration and exposure, but migrants also die from hypothermia or blunt force trauma caused by passing out and hitting their head on a rock.
Brad Jones, a Humane Borders board member and professor with the Global Migration Center at the University of California, Davis, said the most recent data reveals a high proportion of “contemporaneous” deaths—remains of people who died recently—compared with recent years. “There’s estimates that the true number of migrant deaths ranges as high as four times what we’ve seen,” Jones said. “For every migrant’s remains that you find, how many do you not find?” Jones noted that remains are often discovered by “random happenstance”—a hiker or law enforcement officer—and that the desert can quickly obscure or destroy evidence through scavengers and animals.
Octavio Torres, Humane Borders’ executive director, attributed the continued crossings to restrictions on legal entry. “When the current administration is talking about closing the border, I think that they’ve been very effective at closing legal ports of entry and making it darn near impossible for people to actually enter the country or, as certain groups in the country like to say, ‘Come in the right way,’” Torres said.
Amelia Frank-Vitale, an anthropology professor at Princeton University who researches migration, said migrants often feel they have no choice but to make the journey. While researching her book “Leave If You Can: Migration and Violence in Bordered Worlds,” Frank-Vitale traveled to Honduras and met a pregnant woman preparing to migrate. “This is in the full throes of the Trump administration’s real attacks on immigrants,” Frank-Vitale said. “The actions of ICE are making international news. And still, she thought the best thing for her at this moment is maybe to try and get to the United States.”
Torres traced the current pattern back to the 1994 Clinton-era border enforcement strategy known as Operation Gatekeeper. “Ever since Operation Gatekeeper in 1994 under the Clinton administration, it’s all been about prevention through deterrence,” Torres said, referring to the strategy that made crossing in safer, more obvious places extremely difficult. “Out of desperation, people think, ‘How else can I get in?’ And that’s what has driven people into the Arizona desert for the last 32 years.”
The Trump administration has turned the CBP One app from a digital appointment-maker into a means of encouraging “self-deportation” and has revived policies that require many asylum seekers to remain in Mexico while their cases proceed. Border “encounters”—law enforcement contacts at or between ports of entry—have plummeted since the Biden administration, according to government data, but people continue to make the journey, and according to experts, the routes are now harder and more lethal.
Jones compared the resulting deaths to a hypothetical aviation disaster. “Suppose that every single July for 26 years straight, a Boeing 737 with between 100 and 250 passengers crashed right in the Arizona desert,” he said. “We’d be up in arms. You’d be freaking out.” One difference, he acknowledged, is that deaths in the desert come in “dribs and drabs.” “But when you accumulate them,” he added, “we’re talking large numbers of deaths in any given year.”