i work in a petstore so i run into the opposite end of this problem .. we get a lot of people who want to buy a turtle but are not willing to invest money in them.. petco has a good policy to remedy this (i can refuse to sell them the turtle and they will back me up) but it is hard to ensure that they wont just come back when im not there or lie about what they are going to come back and get later.. i wont sell them unless the person buys at least an appropriate sized tank and all necessary lights and a heater... the problem that i run into is other employees that sell them when im not available.. and that dont understand or care enough to make sure the customer realizes what a commitment and investment they are..
im thrilled that you are willing to spend the money to take care of them and take responsibility for thier welfare.. as a few others posted, i urge you to call the FDA on the petstore they were bought from.. this sort of thing is far too common and although customers can sometimes claim innocence, the stores are usually aware that this is illegal.. i live in georgia and every summer have flocks of people who buy "quarter turtles" in florida while on vacation ..some vendors will even lie and say that they stay that small and will live in a fish bowl happily ever after.. if more people would report this type of thing, maybe the law would be taken more seriously.. i have threatened to call the FDA on a petstore i used to work at after my boss thought it would be a great idea to sell baby alligator snappers and yellowbelly sliders (yellowbellys are native and illegal to sell and alligator snappers are a threatened species).. the turtles were sent back to the vendor as soon as i told him i would report him.
mostly i just wanted to applaud you on doing the research and deciding to provide them with the necessary environment.. a lot of people would have just let them die, whether through ignorance or just not caring enough to take responsibility for them..
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my pets: clown treefrogs, reed frogs, big eyed treefrogs, tiger leg monkey frogs, gray treefrogs, milk frogs, cuban treefrogs, whites tree frog, green treefrogs, squirrel treefrogs, blue webbed gliding treefrog, chameleon treefrogs?, dusky salamanders, tiger salamander, veiled chameleon, box turtles, mud turtle, map turtle, yellowbelly slider, florida softshell, two saltwater tanks, four cats, two chinchillas, and a boyfriend.