We are lucky enough when we went at Key Biscayne beach parks a couple of weeks ago that has a Crandon park gardens in the same area. Literally, it's just a foot steps away from the Cabana my friends renting. Our friend said (they grew up and live in Miami) this area at crandon park gardens is used to be the original Miami Zoo before they moved the animals into the massive area of some other place in Miami. This place is now a protected gardens though there are still few animals (mostly birds and goose) live here wander around the area that's why they strict us to abide the rules.
If you're a nature lovers, a garden and animal lovers, or in-love with your partner bring her or him at this quaint garden. A very romantic place.