Chickens are intelligent and emotional creatures capable of feeling pain, frustration and even empathy. They’re known for their chatter, using over 24 distinct sounds to communicate about food, danger, and their feelings. A mother hen starts talking to her chicks while they’re still in the egg, helping them recognise her voice.
Every day at hatcheries, day-old chicks are placed on a conveyor belt for sorting. Males and any chicks deemed sick or injured are sent straight to their deaths—either dropped alive into a grinding machine or gassed with CO2. In Australia, 12 million chicks are killed on their first day of life every year. This routine mass killing is legal across all egg production systems—cage, barn, organic and free-range.
Healthy female chicks are sent to intensive facilities to be raised until they reach the size needed for egg production. Hens lay eggs as part of their menstrual cycle. The natural egg-laying cycle of a hen is about once a month. But through genetic modification, drug use, forced molting and light manipulation, humans have engineered egg-laying hens to produce an egg almost every day. As you can imagine, this takes a major toll on their bodies.
Battery cages, an extreme form of factory farming, keep hens crammed together in stacked wire cages. These sociable birds are denied natural behaviours like foraging and dust-bathing, never feeling sunlight or even stretching their wings.
The use of battery cages is an outdated practice legalised in Australia under the national codes of practice. Developed in the 1990s before advances in animal welfare science, the former code governing poultry welfare has now been replaced by the new Australian Animal Welfare Standards and Guidelines for Poultry. This new legislation has set a nationwide phase-out of battery cages by 2036. However, this long transition means 55 million hens will continue to suffer, underscoring the urgent need for state and territory governments to speed up the phase-out.
Every single egg-laying hen is killed when her egg production drops below industry standard, usually at just 18 months old. The egg industry cruelly exploits the female reproductive system, and then discards the hens when they’re no longer deemed useful.
What about ‘free-range’?
Conditions in free-range egg systems vary, with some smaller producers sticking to 1,500 birds per hectare as the recommended maximum. Yet regulations endorsed in 2018 allow farmers to cram 10,000 hens per hectare and still label their eggs as ‘free range’. This equates to just 1.5 sheets of A4 paper worth of space per hen. Moreover, outdoor access doesn't guarantee that hens can actually get outside; it only requires a door they could theoretically use, even if blocked by crowded conditions.
It’s a common misconception that chickens don’t impact climate change since they don’t produce methane like cows. In fact, the land used to grow corn and soy for chicken feed contributes to deforestation, which drives carbon emissions and destroys habitats.
Most critical is the pollution caused by the enormous amount of waste. Chicken manure releases nitrous oxide, a greenhouse gas even more potent than methane. While the pig and dairy industries produce more manure than the chicken and egg industries, litter–the mixture of manure and dead bodies the chickens are forced to bed in–has 4 times the nitrogen and 24 times the phosphorus of waste from pigs and cows.
Although this can make chicken manure a useful fertiliser, it’s also a major threat to water and soil quality. Farms often spread manure on nearby fields, but when there’s too much, it runs off into waterways. This overload of nitrogen and phosphorus fuels algae growth. As the algae die and decompose, oxygen is depleted from the water, creating ‘dead zones’ where aquatic life can’t survive.
Around large-scale chicken operations, local communities are forced to breathe air thick with dust particles and the stench of ammonia. Beyond the unbearable odours, air pollution from chicken farming poses serious health risks and makes once-thriving areas unlivable.
Eggs are the byproduct of a chicken’s reproductive cycle–akin to a bird’s period. What’s inside that shell? Nutrients intended to grow a chick, including high amounts of cholesterol and saturated fat. Both of these are risk factors for heart disease, the #1 killer in Australia and the world. In fact, for every 300 mg of dietary cholesterol consumed, the risk of death from heart disease increases by 24%. One egg has about 180 mg of cholesterol.
The widespread use of antibiotics in the chicken industry adds another layer of risk. Giving entire flocks antibiotics for growth and disease prevention is common practice in Australia and across the globe. This overuse is contributing to the growing public health threat of antibiotic-resistant infections.
Zoonotic diseases pose an equally severe risk to public health. Chickens are especially concerning because they’re prone to influenza viruses that can quickly mutate and spread to humans. One ‘bird flu’ virus in particular, H5N1, has a shocking 50% fatality rate in humans. To put that in perspective, the deadliest pandemic in human history, the 1918 flu, had a fatality rate of just 2.5%. This danger hit closer to home recently when Australia reported its first human case of H5N1 in May 2024.
