On an early spring day, lkids lined up outside the Cincinnati’s Zoo’s giraffe habitat, waiting for an opportunity to feed the animals over a fence.
One of the giraffes, Zoey, ambled over, sticking her purple tongue out, swiping a leaf and biting down with a crunch.
Her afternoon snack wasn't grown on a farm thousands of miles away.
Instead, it was produced hydroponically in a storage container less than a mile from her habitat.
Last year, the Cincinnati Zoo started growing some food for its animals on-site. It cultivates rows of lettuce and kale without soil in two hydroponic pods. The plants get nutrients from fertilizers, water and LED lights.
Hydroponics technician Zack Burns said the initiative began as an effort to be more sustainable and resilient to food supply disruptions, like supply chain issues.
“Then, also, to give us a little bit of a backup, just in case there were something to happen in the world – natural disasters, pathogenic recalls, like E. coli, Salmonella, things like that – that might shorten the supply,” Burns said.
The zoo has grown more than 10,000 pounds of produce hydroponically since then, Burns said. That’s been enough to supplement the giraffes’ diet with visitor feedings of homegrown lettuce.
“We also grow kale to feed our manatees, and then we usually have a little bit of excess lettuce that will send other herbivores, like the elephants,” Burns said.
Who else is using hydroponics?
Cincinnati is not the only zoo producing its own food and sourcing items locally. Mike Maslanka, senior nutritionist at the Smithsonian National Zoo and chair of the Association of Zoos and Aquariums’ nutrition advisory group, estimates every one of the 238 AZA-accredited institutions is growing or sourcing at least some of their animals’ food locally.
“So, that's whole prey, that's insects, that's bamboo and brows, hay, produce,” Maslanka said.
But, the number of zoos using hydroponics is smaller. Neither of zoos in Cleveland or Columbus currently grow food hydroponically.
Maslanka said that could be due to high costs of the technology.
“The hydroponic thing is cool, but I don't necessarily know if there's a ton of places that are doing it, just primarily because of the break-even expense,” Maslanka said. “But, as that becomes better and more affordable, that may end up being something that people look at down the road, especially on a seasonal basis for providing different types of leafy greens.”
The Cincinnati Zoo said despite the up-front investment, it’s already seeing a financial benefit.
Sustainability project manager Megan O’Keefe said over the past year, the zoo tracked the price of outsourced lettuce. One week, it would cost $35 a box, then the next it would be double that because of a drought or disease outbreak.
“Not relying on vendor lettuce, having a constant fresh, healthy supply here at the zoo is actually proving to be fiscally beneficial for us in ways, because we don't have to stress out about that market variability,” O’Keefe said.
Ideas for the future: ‘a massive food production facility’
While the zoo’s current hydroponic system can’t completely feed the giraffes, let alone all the animals, O’Keefe said the zoo is now considering how to increase its food production.
One idea is to make a bigger growing pod, and even combine it with the zoo’s traditional farming operations in Warren and Clermont Counties, O’Keefe says. There, the zoo is already growing thousands of barrels of hay and close to 100,000 pounds of other food for the animals every year.
“It would make sense to put a custom facility where we can grow hydroponic lettuce on one of those farm properties, and really have a massive food production facility, essentially,” O’Keefe said.
In the meantime, the giraffes will keep enjoying their homegrown treat, courtesy of visitors and a hydroponic farm just down the road.