Diamondback terrapins experience a significant physiological change during the fall as they prepare for their extended hibernation period. The fall weight gain is critical because it ensures they have sufficient energy reserves to sustain them through months of reduced activity. This natural preparation involves a gradual increase in feeding which peaks just before the fasting period that begins at the end of October or early November. The fasting stage marks the start of a five-month hibernation, typically initiated in mid-November. During hibernation, diamondback terrapins enter a state of decreased metabolic activity that allows them to survive without food. It is essential for caretakers to understand that feeding should stop at this period to mimic natural cycles and avoid digestive problems. Providing appropriate conditions such as a cool, stable environment with adequate humidity is equally important for the terrapin’s health during this dormancy. Observing changes in behavior and physical condition can help caretakers monitor the terrapins’ readiness for hibernation. Increased sluggishness and reduced appetite are normal signs. As the hibernation progresses, water quality and substrate conditions should be maintained carefully to prevent health issues once the terrapin becomes active again. Proper weight gain in the fall and a correctly timed fasting period ultimately contribute to the diamondback terrapin’s survival and well-being through the winter months. Understanding this seasonal cycle enhances responsible terrapin care for both pet owners and conservationists, supporting the natural rhythms that are vital for these reptiles.