As the animals’ toll on public health and the economy climbs, communities from Texas to New South Wales have begun to wage war on the species – a campaign fought in public parks, on golf courses, on farmland and on street corners at dusk. Italian farmers estimate the boar inflict €100m (£90m) worth of crop damage annually.

The boar destroy property, devour ground-nesting animals – including endangered turtles’ eggs – and crops, such as fragile vine roots and shoots. In January, a group of wild boar crossed a highway south of Milan, leading to a three-car pile-up which killed one driver and injured several more. In addition to spreading disease, wild boar each year cause thousands of road accidents. Boars carry a host of diseases, including tuberculosis, hepatitis E and influenza A, that can make the jump to humans. Although their numbers are increasing as they migrate to the cities, the move is making them – and us – sick. And now they follow us into our dirty, sprawling cities. For years, boar have been fattening up on our crops. At the same time, we entice it with the tides of garbage and wasted food that wash around our cities.

City sprawl is driving the species out of its dwindling natural habitats and forcing it to live alongside us. This is a crisis we have largely inflicted on ourselves. The arrival of wild boar in town squares and city parks is forcing us to confront a new reality: we are bumping up against the limits of urbanisation. In Rome, where I live, boars rooting through uncollected piles of trash have come to symbolise the decline of the city. In Barcelona and Berlin, Houston and Hong Kong, groups of wild boar have been seen roaming around town at all hours.

But more and more, they are drawn to city life. Listed on the World Conservation Union’s most invasive species list, the wild boar does well in just about any environment, from semi-arid plains to alpine forests and marshy grasslands. The low point came in 2013 when a policeman shot at a boar with his service revolver, but hit and maimed his partner instead. For the past decade, Barcelona has been desperately searching for a way to keep the boar from colonising the leafy neighbourhoods – some home to footballers, bankers and celebrities – that back up against Collserola. The encounters between Barcelonan and beast are numerous, peaking in 2016 when police logged 1,187 phone calls about nuisance boars on the loose – wild hogs rooting up turf, munching trash, attacking dogs, plundering cat-feeders, holding up traffic and running into cars.

The hunter call of the wild boar map