Geckos do not truly hibernate when winter arrives. Instead, they enter a similar but distinct state of inactivity called brumation. This slowdown is a natural response to the seasonal drop in temperature and reduced daylight hours. Brumation allows geckos to conserve energy and survive when their environment makes normal activity difficult.
Brumation: A State of Ectothermic Slowdown
Brumation is a biological process unique to ectotherms, or cold-blooded animals, including all reptiles like geckos. Ectotherms cannot internally regulate their body temperature, so their metabolism and activity levels are directly influenced by the temperature of their surroundings. When temperatures decrease, their bodies begin to slow down dramatically.
This differs fundamentally from the deep sleep of hibernation seen in mammals. Hibernating animals (endotherms) actively lower their body temperature and enter a profound state of dormancy where they are difficult to wake. Geckos in brumation remain semi-alert and can be roused, though they are less active, have a reduced appetite, and spend more time hiding. Brumation helps geckos endure unfavorable conditions until the environment becomes more hospitable.
Environmental Triggers and Physical Changes
Brumation is primarily driven by external environmental cues that signal the onset of winter. The most important cues are the reduction in ambient temperature and the decrease in the photoperiod (shortening of daylight hours). Geckos in regions with pronounced seasonal shifts, like the native habitats of leopard geckos, are most likely to brumate readily. Even captive geckos sense these seasonal changes in light and temperature, triggering the physiological response.
As the process begins, the gecko’s internal processes undergo changes in preparation for the inactive period. Their metabolic rate slows down considerably, resulting in a decreased heart rate and a reduction in appetite. A crucial physical change before the full onset of brumation is the complete emptying of the digestive tract. Food left undigested at low temperatures can rot, leading to serious health complications or death.
Managing Brumation in Captive Geckos
For pet owners who wish to facilitate brumation, the gecko must be in optimal health before starting. A veterinarian specializing in exotic animals should perform a pre-brumation check, including a fecal test to rule out internal parasites. Only geckos that are fully mature and have a healthy weight, often indicated by a plump tail, should be considered for brumation.
Inducing brumation must be gradual to prevent stress. Owners should stop offering food approximately two weeks before the planned cooling period to allow the gecko to clear its digestive system completely. The next step involves gradually adjusting the enclosure’s environment over one to two weeks, slowly reducing the light cycle and ambient temperatures. A common brumation temperature range is between 60°F and 72°F, but specific species requirements must always be confirmed.
During the brumation period (30 to 90 days), the gecko should not be fed but must always have access to fresh water. Owners should monitor the gecko weekly, paying attention to its weight. A loss of more than 10% of its original body weight suggests a problem and requires immediate veterinary intervention. To end brumation, the heat and light cycles are reversed, gradually increasing the temperature and day length over a two-week period. Food should only be reintroduced once the gecko is fully active and has returned to its normal, warmer temperatures.