One cannot over-prepare for disasters. Aim for self-sufficiency, because others may not be able to reach you. Remember that you'll have other concerns on your mind, in addition to your herps. You may be responsible for young children or elderly neighbors and, I hate to say it, you may have to opt for your own survival and leave your herps behind. Whether you evacuate with or without your collection, try to ensure the safety and comfort of your animals.
Confinement helps to prevent injury from falls or wounds from fighting.
Our data suggest that hindgut fermentors may tolerate several days of fasting. My experience suggests that a few days of food and water deprivation in previously healthy animals did little lasting harm and recovery is likely for most herps. For myself, I will be just a bit longer recovering from the stress of this emergency. The safety and well-being of your herps are your responsibility. Double-check all equipment.