Corns are crepuscular animals (they are most acvtive at dawn and dusk), and if they are exposed to too much light throughout the day, they may be stressed, not having the safety they need from the cover of approaching darkness.
This is especially true for young corns, which, in the wild, would even more hesitant to move about in the broad daylight, since almost everything around them is a predator.
I've had young corns that, during the day, wouldn't come out of their hides for food or water, if they saw any movement outside of their vivariums at all. But, if they were allowed a little less light, they felt safer, and would move about regularly.
Reptiles are really very sensitive animals, and neonate corns are often especially so. Things we might never consider as being problems can often times be the very thing that sets a young animal off its feed.
Also, these variables in evironment, which are often too numerous for which to completely account, are often the reason that a breeder will sell a hatchling as a proven feeder, but when the new owner gets the little critter, it refuses to eat anything. Then, when it is returned to the breeder, it eats like a pig. Who knows what any single scenario may bring about as a problem for a specific snake, but the number of possibilities is just HUGE!
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Darin Chappell
Hillbilly Herps
PO Box 254
Rogersville, MO 65742