Perth: As a teenager in the 1970s, I worked on a typical dairy farm in England. Fifty cows grazed on lush pastures for most of their long lives, each producing about 12 litres of milk daily. They were loved and cared for by two herdsmen.
About 50 years later, I visited a dairy farm in China. There, 30,000 cows lived indoors. Most of these selectively bred animals wore out after two or three years of producing 30–40 litres of milk every day, after which they were unceremoniously killed.
The workers rarely had contact with the cows. Instead, they sat in offices, programming machines which managed them. This speaks to a huge and very recent shift in how we treat animals. Over the last half century, the human population has soared – and so too our demand for meat, milk and many other animal products. As a result livestock populations have ballooned while living conditions for animals permanently kept inside have drastically worsened.
Even as farmed animals have multiplied, populations of wild animals have crashed. The two trends are deeply connected. Humans convert wildlife habitat into pastures and farms, expanding living space for farm animals at the expense of many other animals.
This cannot continue. Humans must reckon with how we treat the myriad other species on the planet, whether we rely on them or not. As I argue in my new open access book, the growing scarcity of animal species should make us grasp our responsibility towards the welfare of all animal species on the planet, not just those in farms. Efforts to enshrine rights for animals is not enough. The focus has to be on our responsibilities to them, ensuring they lead good lives if in our care – or are left well alone if they are not.
In the last 50 years, two-thirds of all wild animal populations have been lost.
The main cause is habitat loss, as native forest is felled to grow grass for cattle or corn and soya for livestock.
By weight, the world’s farm animals and humans now dwarf the remaining wild animals. Farm animals weigh 630 million tonnes and humans 390 million tonnes, while wild land mammals now weigh just 20 million tonnes and marine mammals 40 million tonnes.
Wildlife numbers have fallen off a cliff across many kingdoms of life. Three quarters of flying insects are gone from monitored areas of Western Europe. One in eight bird species is threatened with extinction worldwide.
On animal welfare, philosophers have long argued one of two positions. The first is known as “utilitarianism”. This approach argues for minimising the bad things in the world and maximising the good things, regardless of who benefits from them, humans or other animals.