Despite being pandered to the masses as enclaves of animal safety and conservation, zoos are terrible places where even the safety of endangered animals is never guaranteed. Unfortunately, zoo animals eating other animals not only happens, it often happens where everyone sees it, patrons included. All it takes for zoo animals to eat other zoo animals is for the dumbest animals - the ones running the zoo - to make a single error, such as letting zoo animals escape. Usually when zookeepers fail to take the proper precautions, zoo animal feeding frenzies occur. That being said, many outrageous zookeeper stories where zoo animals ate each other happened for no obvious reasons at all, leaving people to guess why zoo animals eat other members of their zoo. If you think about what captivity does to humans, you start to wonder what that sort of thing might do to a tiger, gazelle, or lemur.
But sometimes, zoo animals kill each other simply because - as The Lion King puts it, - it's the circle of life. In the real world, sh*t happens, but as a few smart Reddit zookeepers put it, "predation occurs." These wild zookeeper stories of zoo animals eating each other show that same circle of life in action, and give you another reason to simply avoid zoos altogether.
From Redditor /u/aleatorictelevision:
"My favorite story is when I was doing audience shows at an aquarium in New Jersey. We had yellowfin tuna in the ocean tank which was 780,000 gallons, if I recall correctly, maybe 70-by-70-ft wide from overhead. Now, yellowfin are some of the ocean's best and fastest swimmers. They can get up to 45 mph underwater, which is cool when you would see the small school of them zip back and forth in the tank, but they'd have to stop every 70 ft or so because of the wall or make a quick pivot and try to circle around the tank.
So one day I'm helping out with a dive show where divers are in the ocean tank behind a 50 foot tall window and there's amphitheater seating in front of it. The amphitheater is packed with kids on field trips and they're watching as the tuna are zipping back-and-forth from one end of the tank to the other. The show people are yakking on about sea creatures, and the school of tuna are coming back this way full blast. And one of them doesn't make the turn fast enough. So I am looking right at it as it slams into the thick acrylic window at full speed. It went like:
*tuna tuna tuna EXPLOSION*
Now there are other carnivorous animals in this tank, including 11 sand tigers sharks, sand bar sharks, a couple of 17 ft long stingrays, and some loggerhead turtles (not carnivorous but they'll eat whatever) and lunch has been served!
It's a feeding frenzy and the amphitheater of school kids is screaming bloody murder. Chaos erupts! Everyone is shocked. Some kids are trying to run away and climb over each other. The girl with the mic has no idea what to do. The diver in the tank just looks up as the swarming mass of ocean fury is taking place over his head. After about a minute it's more amazing than horrifying and people are glued to their seats.
Eventually the sharks tear the tuna up into so many pieces every thing dissipates and chunks of tuna sail around the tank all day and you can see the turtles biting at a tuna head. Best day at the aquarium ever!"
From Redditor /u/Whiptail:
"My lecturer told us that about a decade ago in the local zoo a prairie dog exhibit was set up beside the cheetahs. Apparently the prairie dogs tunneled their way into the next exhibit and the cheetahs would sit by the holes waiting for a head to pop up."
From Redditor /u/slimpickens42:
"At Disney World they used to release doves at the end of their Beauty and the Beast stage show. They had to stop when the local hawks had figured out the show's schedule and decided to come have a snack after each show."
From Redditor /u/JackXDark:
"I won't name the zoo I worked at, but it's in the south of England. They're all about trying to let the animals seem to be in as natural an environment as possible, with a minimum of fencing or bars between them and the public. In some cases, that means putting ones that weren't likely to swim on small islands in large ponds, with covered bridges connecting back to their houses. It's fairly artificial, as there's an enclosure all around the outside, but it's carefully structured so that it gives the impression of openness.
But, essentially, what you've got, is monkeys (macaques, if I recall correctly, it's been a while) on an island in a large pond. So, of course, you get water birds landing on the pond. They're wary of the monkeys and don't tend to go on the island, but one day, a couple of the monkeys have been stashing some of their dinner, and they sit at the side of the pond, throwing the food to the ducks.
A crowd of school kids gather. I stopped to watch too.
'Aaawww, lookit da cute monkeys feeding the duckies...' I think you can see where this is going.
These two monkeys are luring the ducks onto their island. Stupid ducks, of course, think that the monkeys are just acting like stupid humans do (even though they're not supposed to), so they venture onto the island.
Another couple of the monkeys have been waiting in ambush to the side, and the first duck hops onto the island and has some more monkey food... Seems legit, so a second and then a third duck follow. As soon as there is an even number of ducks and monkeys who are in on the plan, the scene changes. The monkeys run in at great speed, grab their ducks, rip their heads off, and howl in victory, like a predator that's just taken a spine.
What happens next is that the schoolkids all burst into tears (and a couple of the duck heads were thrown their way too, exacerbating the horror), and the rest of the troupe of monkeys notice what's happened, so they launch themselves at the hunter-monkeys and everything degenerates into a terrible scene of flying feathers and blood, screaming schoolchildren, and monkey-on-monkey violence that seemed to include more mounting and humping than hitting or biting.
I had to write a report up about this, which some of the zoologists got very excited about. There was also a fence put around the island."