The map below shows recorded migrant deaths in southern Arizona from January 2004 to July 14, 2010.

The map shows trends over time and highlights areas that are particularly lethal for migrants.  The map is not completely comprehensive — there is no official centralized record source for this information, and each organization involved in tracking deaths in this region has its own data set.

It is also important to note that some bodies are never recovered. They might be too isolated to be encountered by passersby, or may completely deteriorate before discovery.

The individual deaths displayed within the map come from an extensive database compiled and shared by Humane Borders, a non-governmental organization based in Tucson, Ariz. The author and keeper of the database, John Chamblee, Ph.D., collects and painstakingly cross-checks information on migrant deaths, comparing local law enforcement and medical examiner records to Border Patrol records, to verify location and date.  Along with the data released by Humane Borders, Chamblee provided detailed reports on the methodologies of his work.

Demographic characteristics shown within the map were drawn from databases released by the Pima County Office of the Medical Examiner and the Cochise County Office of the Medical Examiner.  Each data set was compared and cross-checked for consistency, and spot checked against individual case files obtained through records requests with medical examiners and law enforcement agencies.  Once each county data set was verified, category names — such as gender and age — were standardized for the compilation of a single database.