Leachianus Gecko Care Guide

Leachianus geckos (Rhacodactylus leachianus) are the largest living gecko species, renowned for their impressive size, distinctive vocalizations, and variable coloration. Endemic to New Caledonia, these remarkable reptiles inhabit forested environments across Grande Terre and several surrounding islands, where they spend much of their lives concealed within tree hollows and dense vegetation.

Understanding their natural history is essential to providing appropriate captive care. Their substantial size, arboreal lifestyle, and territorial behavior require spacious, structurally complex enclosures and careful attention to environmental conditions.

Natural Habitat & Behavior

In the wild, leachianus geckos inhabit humid forests, utilizing tree trunks, cavities, and dense vegetation for shelter. They are primarily nocturnal, emerging after dusk to forage for fruit, insects, and other available food sources. Their powerful jaws, prehensile tails, and specialized toe pads allow them to navigate substantial vertical surfaces with ease. Leachianus geckos are territorial, particularly toward unfamiliar individuals, and may exhibit defensive behaviors when disturbed. Geographic populations vary considerably in adult size, coloration, and morphology.

Enclosure Requirements

Adult leachianus geckos require spacious, vertically oriented enclosures with substantial climbing structures. A minimum enclosure size of 24” x 18” x 36” is recommended for a single adult, although larger enclosures such as 24” x 24” x 48” provide additional opportunities for movement and environmental enrichment. Large cork rounds, hollow logs, sturdy branches, and textured backgrounds should be incorporated to recreate the complex arboreal environments these animals naturally occupy.

All climbing structures must be securely anchored to support the weight of an adult gecko. Multiple elevated hides and enclosed cork hollows provide essential security, while dense vegetation and visual barriers encourage natural behavior and reduce stress.

Temperature & Heating

Leachianus geckos thrive in moderate temperatures, with daytime ambient temperatures maintained between 72–78°F (22–26°C) and nighttime temperatures dropping to approximately 65–72°F (18–22°C). Prolonged exposure to temperatures exceeding 82°F can cause significant stress and should be avoided. Supplemental heating is generally unnecessary in climate-controlled environments, although low-output overhead heating may be used when needed. Heat mats are not recommended, as they provide limited benefit for an arboreal species.

Lighting & UVB

Although primarily nocturnal, leachianus geckos benefit from low-level UVB exposure. Appropriate UVB lighting supports vitamin D₃ synthesis and calcium metabolism, particularly in growing juveniles and reproductively active females. Low-output fixtures such as the Arcadia ShadeDweller can provide suitable exposure when installed at appropriate distances. Dense foliage and shaded retreats should always be available to allow animals to regulate their exposure. A consistent 12-hour day–night cycle supports normal biological rhythms.

Humidity & Hydration

Humidity should fluctuate naturally throughout the day rather than remain consistently elevated. Daytime humidity levels of approximately 50–70% are appropriate, with evening misting temporarily increasing humidity to 70–80% or higher. Enclosures should be allowed to dry between misting sessions to prevent stagnant conditions and excessive microbial growth. Adequate ventilation is essential, particularly in heavily planted enclosures. Fresh drinking water should always be provided, as leachianus geckos may drink from both standing water and droplets collected on foliage.

Substrate

At Hollywood Hills Exotics, my animals are maintained in naturalistic bioactive enclosures using a homemade ABG-style substrate mix. A well-draining substrate incorporating organic materials, topped with leaf litter, helps support beneficial microfauna and maintain environmental stability. Bioactive setups are particularly well suited to leachianus geckos when properly established, although their substantial weight and climbing activity require durable plants and securely positioned hardscape. Substrate should retain some moisture without becoming waterlogged.

Diet & Nutrition

Leachianus geckos are omnivorous, consuming a combination of fruit, invertebrates, and occasionally small vertebrates in their natural habitat. A nutritionally complete commercial gecko diet should form the foundation of their captive nutrition, supplemented regularly with appropriately sized live insects such as dubia roaches, crickets, and silkworms. At Hollywood Hills Exotics, Vital Meal is used as the primary prepared diet, with live feeders offered to encourage natural hunting behavior and provide dietary variety.

Juveniles benefit from more frequent feeding to support growth, while adults should be fed according to body condition, activity, and reproductive status. Feeder insects should be gut-loaded and supplemented with calcium as appropriate. Reproductively active females may require additional calcium and nutritional support during egg production. Occasional appropriately sized whole-prey items may be offered to suitable adults, although these should not replace a balanced staple diet or be relied upon as a primary protein source.

Lifespan & Common Health Needs

Leachianus geckos are exceptionally long-lived reptiles, with captive individuals potentially living 20–30 years or longer. Their considerable lifespan makes appropriate husbandry a substantial long-term commitment. Common health concerns include obesity, dehydration, retained shed, metabolic bone disease, and injuries resulting from improper enclosure construction or incompatible housing. Balanced nutrition, appropriate UVB exposure, humidity cycling, and regular monitoring of body condition are essential to maintaining long-term health.

Housing Multiple Geckos

Important Safety Information

Leachianus geckos are territorial animals, and cohabitation carries a significant risk of aggression and injury. For this reason:

• Leachianus geckos should generally be housed individually.
• Males should never be housed together.
• Female pairs should not be assumed compatible.
• Established, bonded breeding pairs may be cohabitated in an adequately large enclosure with sufficient space, multiple retreats, and careful supervision.

Even established breeding pairs may exhibit aggression, particularly during reproductive activity or environmental changes. Compatibility should be evaluated continuously, and animals should be separated immediately if persistent chasing, biting, food competition, or other signs of stress occur. Individual housing remains the safest default and allows for more accurate monitoring of feeding, health, and behavior.