* I often struggle with this practice that seems to be widely acceptable within the zoo communities. Even many of my private friends and acquaintances that keep large tortoises follow the same pattern keeping gallops, aldabras, and sulcatas within the same habitat or enclosure. Not to mention the parasite and medicinal reasons but that both the gallop and sulcatas species tend to be territorial and naturally more aggressive than the aldabra species. Aldabras do not know how to defend or cope this this behavior and often become stressed and even can be greatly injured!
* I recently was asked to give an opinion on two sub-adult aldabras that was local. They were just shipped in from out of state and being housed with about an eighty pound male sulcata. The entire time we were visiting the male sulcata was relentlessly ramming both aldabras.
Zoos do it in ignorance, misinformation, or simply lack of space. I cringe when I see zoos mixing species; it's a recipe for trouble. Even worse when they mix aquatic/semi-aquatics with tortoises. At the Toronto Zoo I remember seeing an Indian star, a Burmese star, a flowerback box turtle, Burmese brown tortoises, and spiny turtles in a SINGLE enclosure.