Migrant deaths on the US-Mexico border

Authored by Julia Black at
IOM's Global Migration Data Analysis Centre

Migrant deaths on the rise on the US-Mexico border
Analysis of Missing Migrants Project data
1 January –  31 July 2017


Despite the fact that fewer migrants seem to be crossing into the United States in 2017, more people are dying on this route. The US Border Patrol has apprehended 140,024 migrants between January and June 2017, about half the number (267,746) recorded in the first six months of 2016.1  Despite this large decrease in apprehensions, the number of migrant fatalities recorded in 2017 are higher than in the same period of 2016. 239 migrant fatalities have been recorded in 2017, an increase of 17 per cent compared with the 204 recorded between 1 January and 31 July 2016.

Migrant apprehensions and fatalities recorded on the US-Mexico border, 2016-2017   

Source: US Customs and Border Patrol, 2017; IOM’s Missing Migrants Project, 2017

On Sunday, 23 July, eight migrants died from heat exposure and asphyxiation in the back of a tractor-trailer in San Antonio, Texas. By Monday morning, another two men had died after hospitalization; another 20 migrants remain in critical condition. This tragedy is a reminder of how migrants continue to risk their lives while pursuing ‘el sueño americano’ – the American dream – or on their migration elsewhere. Between 2014 and 2016, IOM’s Missing Migrants Project recorded more than 1,000 migrant fatalities near the border between the United States and Mexico. Another 239 migrants have died between 1 January and 31 July, 2017.

Migrant fatalities recorded on the US-Mexico border, 2014-2017

Source: IOM’s Missing Migrants Project, 2017
Note: Incidents with more than 50 deaths represent annual reporting from local medical authorities operating on the US side of the border

Those people who lose their lives attempting to reach the United States in this border region often do so due to the extreme natural conditions they face. Most deaths recorded on the US-Mexico border occur in the Arizona desert, with nearly 500 human remains discovered by the Pima County Office of the Medical Examiner in the last three years. Like those who died in Sunday’s tragedy, most are likely to have died of exposure and/or hypothermia – but those who die in the desert are rarely reported. The remoteness of the terrain means that if bodies are discovered, in many or most cases it will be days, weeks, or even months after the moment of death. Since 2014, more than 250 bodies have been discovered in advanced stages of decay in the Arizona desert, including more than 200 skeletal remains. It is likely that many of those who die in the desert are not recovered.2

Many of those pursuing el sueño americano travel from Mexico to Texas, meaning that they must cross the swift-flowing Río Grande in order to reach the United States. In 2017, 57 people have drowned in the border river, a 54 per cent increase over the 37 recorded between 1 January and 31 July 2016. This is likely due to the fact that heavy rainfall in recent months has increased the depth and speed of the border river.3 Nonetheless, migrant deaths in the Río Grande seem to be on the rise in recent years, with 43 such deaths recorded in 2015, and 63 in 2016. However in the case of migration over any body of water, it is difficult to determine the true number of migrant fatalities. There are few official sources on migrant fatalities on the US-Mexico border, and most of those which are available are only updated on an annual basis.4 The only sources of information on migrants who have gone missing in the Río Grande are often statements from survivors or family members. The true number of migrant fatalities in 2017 is likely to be higher than the available data indicate.

The reasons for the recent increase in the number of migrant deaths recorded on the border remain unknown. However, a number of academic papers establish that the United States’ introduction of stricter border policies in the late 1990s were correlated with an increase in migrant fatalities on the US-Mexico border, especially in the Arizona desert;5,6,7 but there has not yet been a similar investigation of the recent trends in migrant fatalities.

Migrant fatalities on the US-Mexico border region represent 65 per cent of the total number recorded by IOM’s Missing Migrants Project in the Americas, and 7 per cent of fatalities recorded worldwide. Further analysis of migrant deaths on the US-Mexico border and globally is provided in IOM’s upcoming report Fatal Journeys Volume 3, to be released in early September.


[2] Reineke, R. (2016) Missing persons and unidentified remains at the United States–Mexico border. Fatal Journeys Volume 2: Identification and Tracing of Dead and Missing Migrants. IOM, Geneva. Available from https://publications.iom.int/books/fatal-journeys-volume-2-identification-and-tracing-dead-and-missing-migrants

[3] IOM Mexico, 2017.

[4] The Pima County Office of the Medical Examiner is a notable exception, as they publish their data on migrant fatalities on the Humane Borders website on a monthly basis. See http://www.humaneborders.info/app/mapa.asp.

[5] Rubio-Goldsmith, R. et al. (2006) The “Funnel Effect” and Recovered Bodies of Unauthorized Migrants Processed by the Pima County Office of the Medical Examiner, 1990-2005. Tucson, Arizona: University of Arizona.

[6] Cornelius W. (2001) Death at the border: efficacy and unintended consequences of U.S. immigration control policy. Population and Development Review, 27:661-685.

[7] Eschbach K., J. Hagan and N. Rodriguez. (2001) Causes and Trends in Migrant Deaths along the U.S. Mexico Border, 1985-1998. Houston, Texas: University of Houston.



Data collection and analysis is from IOM's Global Migration Data Analysis Centre in Berlin, Germany. All numbers in this paper are current only as of the date of publication (08/2017) and should be seen as approximations which nonetheless reflect the scale and trends of those who die during their journey for a better life. 

This material has been funded by UK Aid from the UK government; however, the views expressed do not necessarily reflect the UK government’s official policies.


Missing Migrants Project by International Organization for Migration (IOM) is licensed under a Creative Commons Attribution 4.0 International License.
Based on a work at http://missingmigrants.iom.int