A lynx at Schorfheide Wildlife Park in Germany.Patrick Pleul/dpa/ZUMA

This story was originally published by the Guardian and is reproduced here as part of the Climate Desk collaboration.

The lynxes of the Białowieża forest once freely prowled through 548 square miles of ancient woodland. Then, in 2022, the habitat was abruptly sliced in two. Poland built a 115-mile wall across its border with Belarus to stop refugees and migrants entering the EU. About 15 lynxes were left stranded on the Polish side of the forest, forced into a genetic bottleneck.

The 18-foot-high barrier, which is topped with wire and cameras, also dissects the forest’s population of bison, wolves, and elk. Researchers monitored 10 sites along the border, walking along sections and counting signs of humans and wildlife.

“I could not have foreseen the diversity of impacts that we ended up finding,” says the lead author of the report, Katarzyna Nowak, from the Polish Academy of Sciences’ Mammal Research Institute.

There are now an estimated 74 border walls globally, up from six in 1989, with more in the pipeline.

Humans have been building walls for thousands of years, but the speed and scale with which they are now being constructed has ballooned over recent decades.

With refugee crises in Europe and Asia, and the rise of governments cracking down on immigration, the planet is increasingly crisscrossed with steel barriers, chain-link fencing and razor wire—with significant consequences for wildlife.

There are now an estimated 74 border walls globally, up from 

© Mother Jones