Marni LaFleur
San Diago, USA, February 12, 2025
President Donald Trump closed much of the activity at the US-Mexico border in January 2025, making it impossible for migrants who arrive at a US port of entry to apply for asylum.
Mr Trump’s border policies are likely to make it far more difficult and dangerous for migrants trying to reach the US but will not deter all people who want to cross the US-Mexico border without legal authorisation.
The number of migrants crossing from Mexico into the US without legal authorisation dropped dramatically in 2024. But for a long time, crossing the US-Mexico border by land has been the world’s deadliest migration route. US Customs and Border Protection recovered the remains of 10,784 migrants from 1988 through 2024.
This figure is an estimate of the total number of migrants who have died trying to cross from Mexico into the US – there is no centralised system or organisation that tracks migrant deaths or any federal laws guiding authorities on how to manage the remains of migrants.
Many other dead migrants are also never found.
I am a Professor of Anthropology and have spent the past several years trying to understand how and why migrants die trying to enter the US.
Stranded migrants who are now staying in Mexican border towns and others with plans to still try to illegally cross into the US might pursue increasingly dangerous ways to enter the country.
Research shows that there are three main reasons why migrants die trying to reach the US from Mexico. First, migrants are often exposed to extreme weather conditions. Second, they drown in rivers or other bodies of water. Third, they could also experience blunt force trauma because of falls or motor vehicle accidents.
A white-and-green pickup truck is at the top of a river bank. Near the river is a body lying face down.
Dangerous environmental exposure
Migrants coming from Central and South America often travel to the US in groups, typically with the help of a guide called a coyote they pay to help them.
They may spend days or weeks walking through remote areas without access to shelter, fresh food, and clean water. They might sleep outdoors in very cold weather and walk during extreme heat. This can cause hypothermia or hyperthermia.
One of those remote areas is the Sonoran Desert, which spans the southwest US into Northwest Mexico. It is divided by the US-Mexico border and is one of the hottest places on Earth. Ambient temperatures can soar to or above 118 degrees Fahrenheit, or 480 C.
As part of the strategy to stop migrants from coming to the US, Customs and Border Protection does not place many officers in the depths of the desert along the border.
The government’s 1994 migration “prevention through deterrence” strategy explains that because the desert itself poses a mortal danger to individuals, it is unnecessary to guard the land.
With border barriers, video surveillance, bright lights and many patrol agents closer to more populated areas along the US-Mexico border, migrants can view the desert as a viable alternative for entering the US.
Deterrent practices have been found to not stop migrants from trying to enter the US, but they do increase the number of migrants who die trying to do so.
Even migrants who are near help or are rescued from the desert may not recover from exposure to extreme temperatures. In 2023, for example, a nine-year-old migrant boy died from organ failure after authorities found him along the Arizona border.
Drowning poses another risk
Drowning is another leading cause of death for migrants trying to reach the US.
In California, for example, the 82-mile-long All-American Canal runs parallel to the US-Mexico border. Although the canal doesn’t look particularly dangerous, it is deep, cold, fast-moving and has steep concrete edges that are difficult to scale. Migrants might not be able to swim, or others, particularly women and children, are not strong enough to withstand the force of the currents.
Areas of the Rio Grande, a River that divides the US and Mexico in some areas of Texas, have become hot spots for migrant drownings. Approximately 1107 migrants died trying to cross this River between 2017 to 2023. It is fast and deep and is filled with rocks and heavy vegetation that make crossing difficult.
Additionally, to further deter migrant crossing at Eagle Pass, an area of the Rio Grande, the Texas National Guard installed more than 100 miles of razor wire along the river’s banks in 2024. They set up a large string of oversised orange buoys in the water, creating what the federal government called a navigation obstruction for migrants.
These tactics have sparked larger debates on how to handle migration and which government agency is responsible for preventing people from crossing into the country or apprehending them when they do so.
In 2024, a Mexican woman and her two children tried to cross the Rio Grande but struggled to do so. As Customs and Border Protection agents prepared to rescue the distressed and drowning individuals, the Texas National Guard prevented rescue attempts. The family died from drowning, and their bodies were later recovered.
Blunt force trauma
Another leading cause of death of migrants is falling from heights or experiencing car accidents.
At the California border region alone, approximately 20% of migrant deaths were due to blunt force trauma between 2018 through 2023. This rate rose after the 2020 expansion of the border wall, which now spans 741 miles of the US-Mexico border. In total, the border is nearly 2000 miles.
In one incident in Texas in 2020, a pregnant 19-year-old Guatemalan woman died after falling from the border wall, which ranges from 18 to 30 feet. Medical authorities were unable to save the fetus.
In Texas, between 2021 and 2023, high-speed chases by immigration officials led to the deaths of 74 people. Some individuals were ejected from moving vehicles, while others were hit by fast-moving vehicles. Another particularly deadly accident occurred in 2021 in Holtville, California, when an SUV transporting 25 migrants collided with a semi-truck. Thirteen migrants were killed.
A woman wrapped in a foil blanket sleeps on the floor next to a child, surrounded by dry shrubs.
Prevention through deterrence
For more than 30 years, the US government has tried to prevent migrants from reaching the US through different strategies, like deploying Border Patrol agents or building walls.
There are many practical and policy-based interventions that would make it safer for migrants to cross through the US and Mexico deserts. For example, water stations along known migration routes of the desert save lives.
Regardless of how the Trump administration tries to stop migrants from reaching the US, people will likely still try to come and embark on unsafe journeys to do so – and I will continue to track their experiences and deaths.
Marni LaFleur is an Assistant Professor of Anthropology at the University of San Diego. The above article, which appeared in The Conversation, has been published under Creative Commons.
