26 March, 2024

India Bourke London, UK Hello and welcome to this week's Future Earth. I'm India Bourke, a climate and environment reporter for the BBC. Lately I've been looking into the impacts of a spirited creature that has been romping its way through the North American landscape: the bag-snatching, crop-disrupting, unruly wild boar. These animals are on the rise, wreaking havoc as they go but perhaps also boosting biodiversity. As I found out, their climate impact is one of the next big questions to solve. Also in today's edition, lithium battery alternatives and, wait, which epoch are we in again?

CLIMATE CONVERSATION Conservation's wild boar conundrum A wild boar at large in the UK's Forest of Dean. Credit: Getty Images You don't forget your first wild boar encounter. Mine was in Hong Kong: just a short jog uphill, where the high-rise metropolis fades to jungle solitude. Or so it felt until one night I met a large, dark shape – planted in the path ahead. ‌ I had no reference point for how to respond. Should I shout and scare it away, as I would with a London fox? Or turn and run back the way I'd come? Something about the creature's muscular immobility suggested confrontation was not a sensible option. I hesitated, then turned away. This was no longer the human city I knew; it also belonged to something else entirely. ‌ In the end, momentary fear and mild inconvenience were all I had to face. Yet, elsewhere, wild boar cause much more of a stir. ‌ In the US, non-native, fast-breeding hybrids now reach across 35 states. Their rootling, rummaging ways are a torment to gardeners, golfers and farmers alike. In urban Europe, everyone from popstars to police have been shaken by run-ins with the growing population.

Wild boar have roamed far and wide, from Europe to US and Canada. Credit: Getty Images. Plus, there are macro challenges that boar and their hybrids present: from the annual $2.5bn (£2bn/€2.3bn) in damage to US crops and livestock, to concerns about disease spread. "The worst invasive large mammal on the planet," is how one scientist described the animals to me. ‌ But there is also another way of looking at these divisive animals: one which sees them as wayfinders back to a healthier relationship with the non-human world. ‌ Informed by principles of the rewilding movement, which advocates for landscapes' return to a wilder state, large mammals are coming to be understood as essential ecosystem engineers. From wild cows, to bison and beavers, the return of such free-roaming creatures can help restore landscapes and curb climate change.

Boar's biodiversity boost Even the non-native wild boar can make a positive difference, suggests Marc Hensel, a coastal ecologist at the University of Florida. When we spoke recently, Hensel was enthusiastic about hogs' impact on the region's brackish marshes. In large areas, just one or two plants tend to dominate this habitat. But through up-turning soil and recycling nutrients, Hensel found wild boar greatly increased biodiversity. ‌ "Once the hogs came through and disturbed the area, I had to bring in an expert from the local estuarine reserve to help me identify the dozens of plants that I had never seen before," he says. ‌ Yet what is good for biodiversity is not always immediately good for tackling climate change. A complex climate impact Hensel's research in salt marshes, for example, has found that by decreasing woody cordgrass, which forms a monoculture, wild hogs were also decreasing the ecosystem's ability to stave off drought and capture carbon. Another global study estimated that hog soil disturbance greenhouse gas emissions were equivalent to 1.1 million cars. ‌ Moreover, without natural predators to help keep their numbers in check, boar populations can easily get out of hand. More research into their long-term and widescale environmental impacts, and how to best control them, is therefore urgently needed. ‌ Without such studies, the right way to manage wild boar will remain elusive: a large, dark shape – blocking the path ahead to a better balance with nature. ‌ You can read my full report on this promising yet polarising animal here.

NUMBER OF THE WEEK 50%  The price hike seen in some favourite Easter egg brands, after a humid heatwave blasted West African cocoa crops. The soaring temperatures were made 10 times more likely by climate change.

TAKE A MOMENT Rivals to the lithium battery are charging up Lithium batteries are extraordinarily resource-intensive – but emerging alternatives could be cheaper and greener. Read more

CLIMATE QUIZ What does US President Joe Biden's new regulation on automobiles aim to do? A. Ban the sale of petrol-powered cars in the US by 2035, in line with the European Union's goal B. Lower the average sale price of an EV to less than half of the average US annual salary C. Make more than half of new vehicles sold in the US electric by 2032 Scroll to the bottom of this newsletter for the answer.

THE BIG PICTURE The US wetlands where pythons roam Amy Siewe and her fellow bounty hunters hold up an enormous captured python. Credit: Amy Siewe. Florida's renowned "python huntress" Amy Siewe knows a thing or two about invasive species. It's thought that Burmese pythons originally found their way to Florida's Everglades as pets that escaped the confines of their owners' homes. They certainly made the Everglades their own, with their slithering, muscular population now numbering in the hundreds of thousands. Florida's solution is to pay bounty hunters like Siewe to track down and kill the pythons, in a bid to stem their voracious appetites for the region's mice, squirrels, birds, deer and even allegators. Read Lucy Sherriff's story on Future Planet.

BEFORE YOU GO Pregnant women working in extreme heat can face double the risk of stillbirth and miscarriage. Tulip Mazumdar reports for BBC News. While President Biden pushes EVs in the US, in Canada drivers may soon face an additional tax on their EVs, writes Brennan Doherty. If you're planning to grow your own veg at home this year, know some crops are more climate-friendly than others, as Chris Baraniuk reports.