Pachyderms for peace

HUMANS bear the brunt of war. But other creatures get caught in the crossfire. During Mozambique’s bloody civil war from 1977 to 1992, giraffe and elephant herds in the Gorongosa national park shrank by more than 90%. Between 1983 and 1995, while the Lord’s Resistance Army terrorised Uganda, topi and roan, two species of antelope, were wiped out completely in the country’s Pian Upe reserve.

Sometimes, however, fighting can help conservation. Elephant numbers rebounded when war-torn Rhodesia (now Zimbabwe) became too perilous for poachers in the 1970s. A survey in 2016 identified 35 cases of this “refuge effect” around the world. For some radical environmentalists, the notion that culling humans may be good for animals makes intuitive sense. Yet it is wrong.

Rob Pringle and Joshua Daskin, ecologists at Princeton and Yale Universites, studied 253 populations of large herbivores in protected areas across Africa from 1946 to 2010. More than 70% of African parks were affected by war during this period. Like poachers, researchers steer clear of war zones. So Messrs Pringle and Daskin had to ferret out population estimates from sources beyond the usual academic papers, including faded reports from colonial times.

Their work, published this week in Nature, a scientific journal, confirms that wars do wildlife more harm than good. Not only do they expose animals to bombs and landmines, they increase the demand for ivory and bushmeat, which are used to finance and feed armies. During armed conflicts, local norms and institutions that help protect animals also often break down.

Even one year of war in two otherwise peaceful decades may cause populations to decline. The two researchers also found that the damage depends on how frequently fighting flares up, not how intense it is. This suggests that wildlife suffers chiefly as a result of conflicts’ indirect effects on society rather than their direct toll on the savannah.

This grim conclusion comes with one consolation. Total exterminations such as Pian Upe’s are vanishingly rare. And when hostilities cease and people’s lives return to normal, so do those of other mammals. In Gorongosa, where Mr Pringle and Mr Daskin conduct their own fieldwork, the pachyderms are back to 80% of their pre-war numbers.