Border securityU.S.-Mexico border security barriers affect movement of animals

Published 14 April 2014

Security barriers in national parks on the U.S.-Mexican border which aim to deter illegal migrants are affecting the movements of some native animal species while not necessarily restricting the movement of humans, according to new research.

Security barriers in national parks on the U.S.-Mexican border which aim to deter illegal migrants are affecting the movements of some native animal species while not necessarily restricting the movement of humans, according to new research from the University of Bristol, published today in PLoS ONE.

Because international boundaries can be focal points for trade, illegal activity and development, national parks in their vicinity can be vulnerable to pollution, erosion and hunting as well as smuggling of people and drugs.

There is an increasing trend towards the erection of barriers to counter this illegal activity, which may reduce environmental impacts too. Barriers, however, may restrict native species’ territory, causing an environmental impact of their own.

A University of Bristol release reports that Bristol Ph.D. student Jamie McCallum, now of the Zoological Society of London (ZSL), and colleagues from Bristol’s School of Biological Sciences and ZSL, investigated the impacts of illegal activity and the barriers themselves by using automatically triggered cameras (“camera traps”) to measure the number of humans, native and invasive mammals in four U.S. parks on the Mexican international boundary. Comparisons were made between areas with barriers and those without.

Puma and coati were detected more often in areas without barriers, whereas counts of humans were seemingly unaffected.

— Read more in J. W. McCallum et al., “Conservation on international boundaries: the impact of security barriers on selected terrestrial mammals in four protected areas in Arizona, USA,” PLoS ONE (9 April 2014) (DOI: 10.1371/journal.pone.0093679)