have you put out a chameleon alert in the neighborhood?? Put out a reward. Doesn;t have to be big, but big enough where a 12 year old might bite 
Previous post about indigenous species is true - to a point. Depends where you live. If you live in So. CA or FL a large bird might be attracted. If you live up north it is probably unlikely that a hawk or crow would take it. Just my opinion from doing backyard habitats for wildlife. I think a bird would be somewhat suspicious of its shpe, size and colors (or lack thereof). No nocturnal feeders would get him b/c he is still.
keep looking...
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Chameleon Help & Resource Info
0.1 Veiled Chameleon - Luna
1.0 Beardie - Darwin
0.2 felines - Kyndra and Lita
0.1 African Clawed Frog - Skipper
0.3 Mad. Hissers (2 died ;(
0.1 Chilean Rose Hair Tarantula - Rosa Leigh
0.1 Goliath Bird-Eater Tarantula - Natasha