Gorillas (like other animals) eat their own poop. The term for it is coprophagy. When visitors see this they start screaming "oohhh nooo, he's eating his own poop ... that's disgusting " and most of the time they turn away and even walk away. But it isn't disgusting. It's a normal thing. It also happens in the wild (but less than in zoos).
If you dare to look, you can watch a video of a poop-eating gorilla here.
They eat their poop for a variety of reasons. First, it still contains nutrients. I once saw that it still had pieces of undigested carrot in it. In addition, their poop contains (among other things?) the important vitamin b12. There is no vitamin b12 in the food of gorillas. That only is in animal products and they don't eat/drink that. They really need it though! However, it is produced in their intestines, at the end of their intestinal tract. Because they eat their poop, the chance of some defects is less.
Not all gorillas eat all their poop all of the time.
In Burgers' Zoo there was a gorilla who didn't eat her poop. The result: she was often a little bit ill: had a cold or had the flu. To prevent that from happening as much as possible, they served her tea with vitamin supplements every day. Then suddenly she started eating her poop too and they stopped with the supplements and she was okay from that day on. At one point, some years ago, I witnessed a problem with Bauwi. Also a result of not enough vitamins. He wasn't able to properly move. One of his arms was temporarily 'disabled'. That day I saw him walking upright a lot, with that one arm to his body. A day later it was even worse. A friend of mine was in the zoo and she saw him crawling in stead of walking. Poor boy. Luckily they were able to give him extra supplements and he also started to eat his own poop again.
Their poop isn't disgusting by the way. Ours is, because we eat meat; isn't that what makes it smell so terrible? Gorillas don't eat meat.
Another thing they do is eating boogers. Something a lot of people also dislike. If I hear them saying something about it I sometimes ask "you do that yourself too? ". How else can they know it's gross? My idea, it tastes salty and they don't eat salt and do like that now and then. I also see (mostly) silverbacks taking sweat from under their armpit in the summer to put it in their mouth.
And one more thing: giving up food and eating it again. Most of the time hand reared gorillas do it, but not only hand reared gorillas. The former silverback Kumba in Zoo Antwerp (he died in 2016) did it too and so did the current silverback Matadi (did, I haven't seen him doing it recently; maybe he had to get used to the other food he got in Antwerp?). I see/saw the 3 hand reared gorillas Sindy (Artis), Sangha (GaiaZOO, both Sindy and Sangha aren't alive anymore by the way) and Bokito (Blijdorp) do it regularly. But I never witnessed hand reared Makoua (Burgers' Zoo) do it. Sindy, Sangha and Bokito all have/had their own way to do it. Sanga kept it in her mouth, while her full brother Bokito just throws it out and starts eating it again from the floor. He also shares his vomit with his young kids.
During a visit to Blijdorp on 16 February 2016 I was amazed at Bo and his vomiting. There was a lot of 'liquid'. He was on a top plateau and that liquid dripped down. His daughter Tonka just wiped some of the plateau and licked it up; her bigger sister did it different. (Click here for the photo; I'm not sharing it directly because a lot of people can't stand the look of it).
To end this subject, here a photo of a bachelor from Safaripark Beekse Bergen eating a dung. Although some of you might say it's also disgusting, I still share it here, because it's a nice dung.
