Species keeper protocol

Iguana delicatissima

Lesser Antillean Iguana / West Indian Iguana
A Critically Endangered Lesser Antillean arboreal herbivore. Keep strong sunlight-style heat and UV, high year-round ambient humidity, a pronounced rainfall season, and a permanent deep nesting option for females.

Day air28-32 CSeasonal ambient temperature; do not heat the whole enclosure to basking temperature

Basking surface38-45 CEAZA: broad 38-45 C basking zone year-round

UVI under T5UVI 5-6At normal back height; covered refuges near UVI 0

SeasonWet phase easing / recoveryRainfall and day length are major annual breeding cues

Keeper timer setting

T5 UVB: one hour later on, one hour earlier off

During active care — ON: 1 hour after daylight starts.
OFF: 1 hour before daylight ends.

During hibernation / full brumation: T5 UVB OFF (0 hours). In transition months, keep UVB off while dormant and use the active timer only once the animal is warmed and active.

October: daylight 12.0 h; T5 UVB 10 h.

The active T5 duration is the photoperiod minus two hours. Example: daylight 08:00–20:00 means UVB 09:00–19:00. Follow the monthly UVI strength measured beneath the tube and provide access to shade. This timing rule does not introduce hibernation for species whose schedule has only a mild or active winter rest. If an older combined heat / UV column is present, the new T5 UVB duration column governs UVB timing; existing heat settings are preserved.

UVI beneath the optional T5 tube

Working exposure target

October target at normal back height

UVI 5-6directly under the tube when it is on

Retain adult UVI 5-6: EAZA species-specific guidance supports it. The juvenile recommendation is 3-4, with a full gradient to shade. Adult values should not be copied to juveniles.

Your measuring point

Measure at the animal's normal back height directly beneath the brightest accessible part of the T5 strip, positioned toward the middle/back. The animal can enter and leave this area freely.

Keep a lower-UVI gradient and fully covered refuges near UVI 0. This is the optional exposure area, not the average across the cage.

Use a UV Index meter, such as a Solarmeter 6.5/6.5R. Warm the tube for about 30 minutes; keep reflector, guards and mesh in place. Raise or lower the fixture within its manufacturer's minimum-distance guidance, then recheck the reading and every higher accessible surface.

Evidence level: Species-specific published husbandry guidance. These are working recommendations, often inferred; exact species optima and seasonal UV dose usually have not been measured. Log lamp-on time and animal behaviour as well as UVI.

Baines et al. (2016), UV-Tool · Muryn, Baines and Dishman (2026), Reptile Lighting Guide V10 · EAZA (2023), Iguana delicatissima Best Practice Guidelines

October management

Selected automatically using the Netherlands date

Wet phase easing / recovery

Lesser Antilles - from xeric coastal scrub to mesic forest; exact island provenance strongly affects seasonal rainfall and laying timing

28-32 CDay air

22-26 CNight

38-45 CBasking

5-6T5 UVI*

12.0 hPhotoperiod

10 hT5 UVB duration

68-82 / 82-94%RH day / night*

Daily AM + lighter PM mistRain / mist

7Food days/week

Annual schedule

Scroll sideways on smaller screens

Month	Day air	Night	Basking	T5 UVI*	Photoperiod	T5 UVB duration	RH day / night*	Rain / mist	Food days/week	Seasonal management
January	26-28 C	18-22 C	38-45 C	5-6	10.2 h	8 h 12 m	55-70 / 70-82%	AM mist; 3-4x/wk	6	Dry-season cycling / conditioning
February	26-28 C	18-22 C	38-45 C	5-6	10.5 h	8 h 30 m	55-70 / 70-82%	AM mist; 3-4x/wk	6	Dry season; breeding activity may begin
March	26-30 C	20-24 C	38-45 C	5-6	11.0 h	9 h	58-72 / 72-84%	AM mist; nest available	6	Mating / early laying in mesic lines
April	28-32 C	22-26 C	38-45 C	5-6	11.8 h	9 h 48 m	62-76 / 76-88%	Daily AM mist	6-7	Wet-season transition / gravidity
May	28-32 C	22-26 C	38-45 C	5-6	12.5 h	10 h 30 m	65-80 / 80-92%	Daily AM + PM mist	7	Wet phase / nesting
June	30-34 C	24-28 C	38-45 C	5-6	13.2 h	11 h 12 m	68-82 / 82-94%	AM + PM mist	7	Peak nesting in xeric populations
July	30-34 C	24-28 C	38-45 C	5-6	14.0 h	12 h	68-82 / 82-94%	AM + PM mist	7	Nesting / incubation
August	30-34 C	24-28 C	38-45 C	5-6	13.5 h	11 h 30 m	70-85 / 84-95%	AM + PM mist	7	Late nesting / hatch window
September	30-34 C	24-28 C	38-45 C	5-6	13.0 h	11 h	70-85 / 84-95%	AM + PM mist	7	Hatching / wet-season growth
October	28-32 C	22-26 C	38-45 C	5-6	12.0 h	10 h	68-82 / 82-94%	Daily AM + lighter PM mist	7	Wet phase easing / recovery
November	28-32 C	22-26 C	38-45 C	5-6	11.0 h	9 h	62-78 / 78-90%	Daily AM mist; PM as needed	6-7	Transition to drier season
December	26-30 C	20-24 C	38-45 C	5-6	10.2 h	8 h 12 m	58-72 / 72-85%	AM mist; reduce rain	6	Dry-season reset / conditioning

Keeper notes

Use measured gradients and animal behaviour, not single thermostat readings

T5 UVI measurement

Measure UVI at normal back height directly beneath the brightest accessible part of the optional T5 strip. Place the strip toward the middle/back with free access to and away from it; preserve a gradient into fully covered refuges near UVI 0. These numbers describe the exposure area, not the whole enclosure or a daily average.

UVI review

Retain adult UVI 5-6: EAZA species-specific guidance supports it. The juvenile recommendation is 3-4, with a full gradient to shade. Adult values should not be copied to juveniles.

Taxonomy and conservation

Iguana delicatissima is a full species with no accepted subspecies in the Reptile Database. It is Critically Endangered; island provenance and pedigree should be preserved because hybridization with introduced Iguana iguana is a major threat.

Housing

EAZA recommends at least 180 cm enclosure height, >3 m2 floor area for one adult or >4 m2 for a pair, with larger housing preferred. Use massive branches, broad basking zones, visual barriers and a permanent deep nest area for females.

Heat and UVB

EAZA ambient targets range from about 26-28 C day / 18-22 C night in Jan-Feb to 30-34 C / 24-28 C in Jun-Sep. Keep a broad 38-45 C basking surface all year. Adults: UVI 5-6 at basking, juveniles UVI 3-4, with deep shade available.

Humidity and seasonality

Simulate a hot/wet Apr-May to Oct-Nov phase and a slightly cooler, noticeably drier Nov-Apr phase. 'Dry' means reduced rainfall, not desert air: Lesser Antillean humidity remains relatively high. Morning mist year-round; add an evening mist in the wet season.

Diet

Feed a very diverse herbivorous diet based on dark leafy greens, herbs, safe browse and flowers. Add modest fruit mainly in the wet season. EAZA discourages animal protein and routine commercial iguana pellets.

Breeding

Laying timing varies by island: xeric populations commonly lay one clutch Jun-mid Aug; mesic populations may lay from Feb/Mar into Aug/Sep. Published clutches are commonly in the 4-26 range, with historic island reports reaching about 30.

Nesting / incubation

Keep a permanent nest at least 50 cm deep, compactable and slightly humid, with egg-chamber depth about 28-30 C. EAZA reports successful artificial incubation at 29-31 C for about 83-97 days; eggs are commonly set in moist vermiculite.

Conservation warning

Do not cross or co-house breeding animals with Iguana iguana or uncertain hybrids if conservation-value purity matters. Reproductive females are stress-sensitive and can develop life-threatening dystocia if nesting conditions are inadequate.