Why are some hoofstock, rhino, hippo, and elephant paddocks so barren http://www.zoochat.com/39/elephant-odyssey-asian-elephant-exhibit-near-115805/, while other paddocks are kept lush with vegetation (mainly grass in this case) http://www.zoochat.com/590/7-acre-african-elephant-exhibit-179167/ Does the maintenance of the grass require intensive watering to sustain the plants? Is it more expensive to attempt this especially for elephants and rhinos? But it is more aesthetically pleasing to see grass, is the time and money put in worth it? Why are there such differences in these paddocks (as a lush exhibit will draw much more attention to the usually ignored hoofstock); and how could maintenance be arranged for the larger destructive species?
If we want to look for one simple answer, it is size. You need a very large exhibit for the animals not to ruin the grass. Of course Elephant Odyssey never had grass from day one, but I am pretty sure it would all be gone by now even if it did. Still, the Nashville elephant exhibit is average size, maybe two plus acres, and it is very lush. Perhaps the climate helps (more rain there)? The other factor is if they let the grass grow a bit before adding the large animals. The white rhino exhibit at my zoo (Reid Park) has grass throughout, but it was an antelope or zebra yard for over two decades before the rhino was added. It is also fairly large and is watered at least a couple times a day.
Yes, obviously herbivores, especially large ones, can eat the grass in a paddock exhibit in no time... but, the real reason for (boring, dull, uninspired) hoofstock displays is the simplicity of raking poop. That's the main reason for dirt floors, which is a real shame. I think you could keep a lush, grassy enclosure going with enough water and the occasional tossing of grass seed. Goodness knows it'll be plenty fertilized!
There are many factors: local climate, species of animal kept, species of grass and stocking rate spring to mind as well as the cultivation of the grass. In the UK, it is usual to keep large herbivores on hard standing areas in the winter, when grass is not growing and paddocks can often become muddy and waterlogged - most farm livestock is now kept this way too. It is splendid to see the animals enjoying the first day when they are let out onto the grass in spring. Elephants are now usually kept on sand here - the type of sand must be chosen carefully to avoid foot problems, although some zoos also have grass paddocks for use in the summer (eg Whipsnade, Howletts and Port Lympne). Alan
gentlelemur comes closest to the mark. I would add soil types to that list. Also add whether or not there is irrigation. Also, most zoos do not bother with turf management (which refers in part to fertilization) so the grass is not supported. To add a little explanation: It is not really just about the size of the exhibit: it is more about the density of animals in the exhibit ("stocking rate"). All things being equal, if there is some grass holding on and the number of animals is reduced (or even the hours of the day they have access) the grass may do well. And it depends greatly on which animal(s) are in the exhibit. What elephants do to grass is not like what antelopes do which is further different from what zebras do. If a zoo particularly wants grass then all of this and more must be taken into account. To answer your questions more specifically: I have been involved in several projects with this very goal in mind. And in short, yes, the cost can be daunting and yes, it can be done in most regions (but not all) Sometimes the zoo feels it is not worth the cost and effort (which may be considerable)
Whipsnade's elephant seemed to have plenty of grass, despite having a herd of 9 with dozens of mara, wallabies and Chinese water deer wandering in. I assume that is because they don't spend a huge amount of time in the paddock, wandering around the zoo most of the time.
Are there any grass species that grow quickly and could be used in such paddocks? And how much watering would promote continuous growth?
Species selection really must be tied to soil types, region, and other variables. A custom blend for each situation is wisest IMO Watering also must take into account locale, soil types, drainage and grass types.
That's an odd mix of species. I would imagine that zoos in dry places like southern California or Arizona would not want to water their paddocks as much as the cost would probably get pretty expensive.
The Mara, Chinese water deer, Muntjack deer and Wallabies are free roaming around Whipsnade. Some of the elephants are walked around the zoo most days for an hour or two and obtain browse and grass during these walks. Extra browse and feed is also provided. The elephant paddock is 7 acres and the zoo estate is 600 acres. This gives them quite an advantage regarding grazing.
So, there's no real reason then why the rhinoceros enclosures at the San Francisco Zoo needs to look like a stockyard at a slaughterhouse? I don't think a single rhino could decimate all of the missing grass. Water shouldn't be an issue either.
Exactly what I was thinking when I started this post! I always wondered why it was so barren and the only substrate they use is sand for both black and greater one horned rhinoceroses, especially with the climate
Why not just ask them why they use sand? They may have a local parasite issue, or a curator who has bad experience of keeping rhinos on grass. Zoo visitors often assume the zoo is doing something 'wrong' when there's a good reason for what is happening. Whipsnade, a nice zoo? It was the first big paddock-type zoo in the world, when most zoo hoofstock was in tiny yards. Course it's a nice zoo.
To me sand isn't that bad, if grass is out of the question for one reason or another. It may not be what the animals live on in nature but I doubt it's a bad choice of substrate. Concrete is the one I have a problem with. It seems very cruel for a big animal like an elephant or a rhino to have to stand (and sleep on) concrete. I know how much my knees, feet, and lower back hurt if I stand on a surface like that all the time, I can only imagine how much the knees and feet on an animal that size hurt.