Black Tree Monitor — Fact Sheet
Varanus beccarii · Black Tree Monitor · Black Tree Monitor
📋 At a glance
| Adult size | 90-120 cm |
| Lifespan | 10-15 years |
| Subspecies | No captive-care subspecies split |
| Origin | Varanus beccarii is native to the Aru Islands of Indonesia and nearby New Guinea-region trade context. |
| Activity | Diurnal |
| Difficulty | Expert |
| Legal | CITES: Appendix II; EU: Annex B; local rules still apply |
🏠 Enclosure
- Large secure vivarium; monitors need space, heat, and strong construction
- Adult enclosure should prioritize floor area, deep substrate, climbing, and basking access
- Substrate: deep packed soil/sand/clay mix that supports digging
- Avoid small tanks, weak lids, loose unstable rock piles, and underpowered heat
🪨 Enclosure furniture
- Large basking platform, deep diggable substrate, secure hides, climbing branches or rock ledges
- Humid retreat below the dry surface
- Heavy decor must be supported from the floor, not resting on loose substrate
💡 Lighting
- Strong UVB and intense visible light are essential
- Best: linear high-output UVB plus bright LED/halide-style visible lighting and separate basking lamps
- Measure basking UVI and replace lamps on schedule
- Photoperiod: 10-12 h; no visible light at night
🌡️ Temperature
Basking spot: 38-45 °C
Warm zone: 28-31 °C
Cool zone: 24-26 °C
Night: 22-24 °C
Clear gradient required; the animal must be able to move between warm, cool, and hidden zones
Measure basking surfaces with an infrared thermometer and ambient zones with digital probes
Avoid heat rocks and unguarded heat sources
💧 Humidity & water
- Dry surface with access to a more humid burrow or retreat for arid species
- Fresh water always available; larger species may need a soaking tub
- Ventilation must remove stale damp air
- Avoid bone-dry deep substrate and swampy floors
🪳 Diet
Feed regularly:
- Appropriately sized crickets, roaches, locusts, and other feeder insects
In moderation:
- Waxworms, mealworms, superworms, and fatty larvae
Avoid:
- Wild-caught insects, oversized prey, spoiled feeders
Supplements:
- Calcium as needed; vitamins in a controlled schedule; UVB does not get replaced by powders
🩺 Health — warning signs
- Lethargy or poor appetite → basking heat too low, stress, or disease
- Soft jaw or weak limbs → UVB/calcium issue
- Obesity → overfeeding or insufficient space
- Nose rub or damaged toes → enclosure stress or unsafe surfaces
- Retained shed on tail/toes → humidity or abrasion problem
Consult a reptile- or exotic-animal veterinarian for severe weakness, injury, breathing signs, swelling, or prolonged refusal to eat.