In the wild, and if given the chance in captivity, JCP's will climb everywhere. They can live happily in a terrestrial cage, but if you give them a branch as adults they will normally sit out so you can look at them.
Being screen, it will not hold the adequate humidity for a JCP to shed successfully. I house mine in custom built cages, which are easily made.
Normally I use particleboard covered on the inside with plastic laminate, a plexiglas frame door, and a pegboard back. The best way to heat it is putting a light fixture in the top and using a high watt bulb or a ceramic heater.
Hope that helps
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Sean McIntyre
Currently have:
0.1 Antherystic Elaphe Guttata Guttata - Corn Snake
1.0 Elaphe Vulpina Gloydi - Eastern Fox Snake
0.1 Leucistic Elaphe Obsoleta Linheimeri - Texas Ratsnake
1.1 Morelia Spilota Cheyni - Jungle Carpet Python
Saving for:
Agkistrodon Contortix Mokasen - Northern Copperhead
Epicrates Cenchria Cenchria - Brazilian Rainbow Boa