Forgive my ignorance, (especially as I am a biology teacher) but could UV play a role in how vibrant an indigo's colors are? These are diurnally active snakes, thus getting exposed to large amounts of UV radiation throughout their lives. Maybe a combination of diet and environment is responsible for the duller colors commonly seen in captivity?
Anyone with red throat babies want to get some UVB bulbs and give it a shot? Or better yet, give me one and I'll do it 
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Chance Duncan
Science Teacher, Herp Enthusiast, and Reptilian Conservation Proponent

