The demand for day-old chicks
German research indicates that 70,000-100,000 chicks per zoo are currently used as feed annually. So, multiplying that with the number of zoos and you can estimate the demand for chicks, right?
Well, estimating the exact number of zoos worldwide is a challenging task, due to various factors. Zoos exist in many countries and range from small private collections to large, accredited zoological parks. Some might be wildlife sanctuaries, rescue centers or animal rehabilitation facilities. Not all facilities that house animals necessarily fall under the category of zoos. On top of that, every zoo houses different kinds of animals with specific diets, so the demand for chicks varies among the zoos, too.
A quick Google search suggests there are around 10,000 zoos worldwide, but according to this research, only 3,000 of these fall into the category of ‘actual zoos.’ Therefore, the global market for day-old chicks would amount to 210 million to 300 million chicks per year, which comes down to 3-4% of all culled chicks worldwide.

The total number of chicks culled each year (6.5 billion)
vs.
The number of chicks used as feed (195-260 million)
Market developments
According to the same Wageningen University study, the European market for zoos and falconries is saturated, so it is expected that the demand for day-old chicks in zoos won’t increase any further. Therefore, companies that process and sell day-old chicks are exploring new markets, such as the pet market.
Pricing and alternatives
So, let’s imagine the supply of day-old chicks comes to an end (which is hopefully quite soon), what will the alternatives be?
The director of the Osnabrück Zoo, ranked as the tenth most visited zoo in German, acknowledges that replacing 50,000 day-old chicks a year with artificial feed is feasible, it’s just more expensive and time-consuming. Also, zoos have existed long before this “waste stream” existed.
There have been suggestions that these chicks might need to be replaced with mice bred specifically for use as feed. But this is very unlikely this will happen, looking at the pricing of these products. According to this research, the price is €0,70-€1.00 per kg of frozen chicks, which is 10 times cheaper than rats and 125 times cheaper than baby mice. Feeding a zoo requires many different ingredients and there are plenty of alternatives to day-old chicks.
So, will we have to close the zoos if we stop chick culling?
Short answer: no.
Long answer: if we stop chick culling, the feed cost of some zoos might increase. But an increase in feed costs doesn’t mean that the zoos cannot exist; there are plenty of alternatives for the zoos to feed their animals with.
Just because the zoos found a purpose for a ‘waste stream’, that doesn’t mean we should keep it intact. Especially so when it consists of billions of animals killed on their first day.