Why can’t some animals be sold or released to wild?

[Nat1984]

I’m a sandbox player and I have noticed that some animals can’t be released to the wild or sold. Why is this?

 

[Merit Selket]

did you check their age? maybe they are too young or too old.

 

[Juztin]

Offspring too.. pregnancy. Not possible to release or send to animal trade center.

 

[jrolson]

Also if you adopt them as someones "pet" they won't know how to take care of themselves in the wild...

 

[Nat1984]

It was a group of Aldabra Giant Tortoise. They were all over 4 years but when I moved them to the trade centre, my only option was to move them back to the habitat.
Yet I had other animals that I had bred and I could sell or release them to the wild once they reached adulthood.

 

[Annageckos]

I haven't have the Aldabra yet, but I'm guessing they aren't adult at that age. Make sure they say they are adult, until then you can't sell them.

 

[Monsarona]

Yeah, Aldabra Tortoises do not reach adulthood until 25 years old. So, you gotta keep em for a while longer. I am pretty sure the Galapagos are the same or similar.