The way humans have changed the forests of Central and South America may be making it impossible for subsistence hunters to continue their way of life, according to two conservation scientists.

“No longer can subsistence hunting be seen or managed as a sustainable activity carried out by small, isolated human groups occupying large tracts of natural habitat and using traditional hunting methods,” Galo Zapata‐Ríos, who directs the science program for the Wildlife Conservation Society’s (WCS) Ecuador program, said in a statement. “Any approach to the problem must take into account the fundamentally different context in which subsistence hunting occurs in the present day.”

Scientists have generally thought that groups that rely on hunting to feed themselves and their families under these conditions — and as it has occurred for generations in some places — could do so without affecting the local survival of certain species.

But Zapata‐Ríos and his colleague, Esteban Suárez, an ecologist and professor at Universidad San Francisco de Quito, say the widespread impacts humans have had in the “neotropical” forests of the Americas force a rethink of those assumptions.

“Any approach to the problem must take into account the fundamentally different context in which subsistence hunting occurs in the present day,” the authors write in a commentary published May 8 in the journal Biotropica.

Deforestation for timber and agriculture has carved through the region’s rainforests, leaving smaller and fewer fragmented refuges for species to inhabit. And an influx of people from outside, whether due to oil exploration, mineral extraction, or tourism, has helped fuel larger-scale hunting, sometimes even commercial-scale, they write.

Add to that even low levels of subsistence hunting pressure, and the burden could be enough to wipe out some species. Not only does that diminish the biodiversity of the surroundings, but it also robs those very communities of a critical source of food, Zapata‐Ríos and Suárez say.

The researchers outline several potential remedies, but acknowledge that none are perfect solutions. Wildlife managers could allow subsistence hunting only of certain animals that are numerous or reproduce swiftly enough to cope with the pressure. Parks and reserves with stronger protections could also provide places where animals can escape hunting pressure and thus keep their numbers up.

The pair’s research also looked at attempts to incentivize communities to switch to livestock rearing as a way to replace the protein in their diet that hunting historically provided, and, more drastically, projects to resettle subsistence hunters outside key areas that are home to rare or threatened species.

One study they cite found that more than two-thirds of a community in India that had been moved from the Bhadra Wildlife Sanctuary “perceived that their quality of life had improved and were satisfied with the outcome of the relocation,” but that’s not always the case.

“There is ample evidence showing that resettlement of human populations in the name of conservation can result in severe social, cultural, and economic impacts that often affect the most marginalized groups among societies,” the team writes.

The researchers say that far-reaching initiatives are necessary if we’re to stem the loss of species from the bevy of threats they face. But they also point out the difficult situation that the outside world’s impacts on the region’s ecosystems have put communities of subsistence hunters in.

“[W]e give them the tools and expectations of the Western World, and then, we hope that they can succeed at living sustainably, even if we have constantly failed,” the authors write.

Banner image of a red howler monkey in Colombia by Rhett A. Butler/Mongabay.