On my last two visits, the staff told me this smaller outdoor enclosure is specifically inteneded to house bulls to replicate their solitary nature in the African wilds. I asked them if the bulls can use the bigger herd yard, and he can use their space occasionaly but the multigenerational herd can't use his space for that matter. When i asked the keepers if the fence can withstand them (now one of my usual questions when talking to elephant keepers at zoos) they told me it's so durable they could harm males trying to ram it, making it super bull proof to me.
