Good question! Glad you asked !
Well, let’s see. They are interesting to observe and study. They are just plain cool to have (I bet not a lot of your friends have them, unless you are talking about friends in the frogger community). They can help you appreciate a particular aspect of Nature that may have gone unnoticed by you previously. They might have the positive effect of turning you into a conservationist which is also cool. They need your help too as many frogs in the pet trade are collected from the wild and their populations are dropping drastically from over harvesting, their natural habitats are in jeopardy and if we aren’t careful they may become extinct.
If you think that keeping a toad, frog, poison dart frog, specifically mantellas, was something you would like to pursue then this blog makes a good starting point as well as several other well established website resources that you will find listed here (resource page coming up shortly. Look for it).
First, I would suggest that you do some studying before you obtain your frogs. Become knowledgeable in regard to what they are, what they need to live, what they need to breed and how you may help the frog community keep the species you are interested in continuing well into the future. Don’t rush into a purchase until you realize what it takes to take care of these little creatures properly. They require properly handling or lack there of more importantly, a properly set up and maintained enclosure, a constant supply of adequate food sources and supplementation, and an opportunity to breed and live where you are the loving observer doing all that you can to help them live out their natural lives.
When you are ready to dive in I suggest you get your hands on an adequate sized tank or terrarium for their enclosure. For mantellas, since they are more terrestrial (leaf litter foragers) than arboreal (tree climbers) what is important is that you give them enough horizontal space to live rather than vertical. Many dart frog are climbers and need more vertical but for the most part almost all the mantella species’ are ground oriented. That isn’t to say that they won’t climb, sometimes for a while that is all that they will do but in time they will return back to the lower level to continue on their business. Because they can climb ensure that the enclosure is properly secured to prevent them from escaping. These little critters can get through surprisingly small holes.
Then there is a matter of ensuring that you have a constant supply of food for said frogs. If you live somewhere that has ample supply of small bugs outside you could go field foraging and take what some call “field sweepings” (basically use a net, swipe it across the grass/bushes and feed your frogs whatever small bugs you happen to capture). If you have a local pet shop near by most carry feeding stock such as crickets, mealworms and such. Be advised that if you are going to care for mantellas that due to their small size they require small meal worms, pinhead crickets (very young crickets), springtails, and wingless fruit flies. If it can’t fit comfortably in their mouths then don’t attempt to feed it to them.
There is the matter of ensuring that you provide an adequate level of moisture in their enclosure as well an acceptable level of heat. Typically the more moist the habitat the better they are but mantellas don’t require access to a huge amount of water such as a toad would. Mantellas require tropical level heating but be careful not to overdo it as most mantellas don’t like an excessively high temp range.
Finally, the frogs themselves. Please do your research and seek out a decent breeder to order your frogs from. This does a number of things – ensures that the frogs you receive have been captive bred which usually means a healthier and hardier frog, it decreases the demand for wild caught specimens removed from their natural habitats, it supports a growing community of frog owners and it is just the responsible and right thing to do. There are a few mantella species that can be found in the frog breeding community and numerous species in the poison dart frogs category from all over the world. You have quite a choice between dendros and mantellas.
Join an online frogger community and enjoy communicating with others on these forums, sharing photos and experiences, learning from more experienced owners and becoming a part of a growing movement.
NOTE: 09/21/2013 This posting will be expanded considerably in a few days.