There is growing evidence that feral dogs and their domestic cousins have a big ecological impact, from hunting and spooking wildlife to poisoning plants and spreading disease to endangered species
27 April 2022
IT WAS shocking,” says biologist Galo Zapata-Ríos, recalling what he saw when he viewed footage from his camera traps. Placed in the Andes, across 2000 square kilometres of forests, grasses and shrublands in Ecuador, these were intended to capture the movements of striped hog-nosed skunks, mountain coatis and other wildlife. Instead, in frame after frame, he saw something he hadn’t anticipated: dogs. “There were so many dogs that I decided to switch my topic,” says Zapata-Ríos, who works for the Wildlife Conservation Society’s Ecuador programme, and now studies the ecological impacts of dogs.
It isn’t just the Andes: dogs are everywhere. They live on every continent except Antarctica, and inhabit high mountains, tropical rainforests, islands and nature reserves that would otherwise be considered pristine. One calculation put their numbers at a billion, making them the most common carnivore on Earth. That was in 2013 and there are surely more today. India alone has seen an estimated increase of 20 million – to around 80 million – partly because of legislation passed in 2001 forbidding the relocation or killing of street dogs. Meanwhile, during pandemic lockdowns, dog ownership soared in some countries including the UK where there are now some 13 million pet dogs.
At a time when nature is under pressure like never before, there is growing evidence that dogs – both free-roaming and home-based – are killing, eating, terrifying and competing with other animals. They pollute watercourses, over-fertilise soils and endanger plants. Such is their impact that …