Species keeper protocol

Cyclura cychlura inornata

Allen Cays Rock Iguana / Northern Exuma Rock Iguana
A critically endangered northern Exuma rock iguana with early-to-mid May mating and a mid-June to mid-July nesting season. Keep intense basking and UV, broad thermal choice, a drier winter and deep compactable nesting substrate.

Day air28-30 CSeasonal northern Exuma ambient temperature with cooler retreats

Basking surface43-47 CBroad local basking zone; not whole-enclosure air temperature

UVI under T5UVI 4-6At normal back height; covered refuges near UVI 0

SeasonMain hatchling emergence / growthMating early-mid May; nesting mid-June to mid-July

Keeper timer setting

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

ON: 1 hour after the daylight lights come on.
OFF: 1 hour before the daylight lights go off.

October: daylight 11.7 h; T5 UVB 9 h 42 m per day.

The T5 runs for two hours less than the total photoperiod. Example: daylight 08:00-20:00 means UVB 09:00-19:00. Keep the monthly UVI strength as listed beneath the tube. Existing care values are preserved.

UVI beneath the optional T5 tube

Working exposure target

October target at normal back height

UVI 4-6directly under the tube when it is on

Replace the blanket UVI 5-7 default with an optional adult T5 patch at UVI 4-6, aiming initially around 5. This is a moderate working choice within published exposure guidance, not proof that 5-7 is harmful or a measured optimum for every Cyclura. Published UV-Tool assignments vary even within the genus; no trial was found that makes UVI 7 a necessary default.

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: Inferred genus-level working range. 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

October management

Selected automatically using the Netherlands date

Main hatchling emergence / growth

Northern Exuma Cays, Bahamas - xeric scrub, limestone and sandy nesting areas

28-30 CDay air

24-26 CNight

43-47 CBasking

4-6T5 UVI*

11.7 hPhotoperiod

9 h 42 mT5 UVB duration

66-80 / 78-90%RH day / night*

Wet phase easingRain / mist

6-7Food 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	25-27 C	20-22 C	42-46 C	4-6	10.8 h	8 h 48 m	55-68 / 68-80%	Dry phase; light AM mist 2-3x/wk	5-6	Cooler dry-season maintenance
February	25-28 C	20-22 C	42-46 C	4-6	11.3 h	9 h 18 m	55-68 / 68-80%	Dry phase; light AM mist 2-3x/wk	5-6	Condition adults; monitor body condition
March	26-29 C	21-23 C	43-47 C	4-6	12.0 h	10 h	58-70 / 70-82%	Dry-to-wet transition; 3x/wk	6	Increase browse / breeder conditioning
April	27-30 C	22-24 C	43-48 C	4-6	12.7 h	10 h 42 m	60-74 / 72-84%	Rain pulses increase	6-7	Courtship conditioning; nest zone prepared
May	28-31 C	24-26 C	44-48 C	4-6	13.3 h	11 h 18 m	64-78 / 76-88%	Wet phase; regular rain pulses	7	Main mating: early to mid-May
June	29-31 C	25-27 C	44-48 C	4-6	13.6 h	11 h 36 m	66-80 / 78-90%	Wet phase; regular rain	7	Nest migration / digging from mid-late June
July	29-32 C	26-27 C	44-48 C	4-6	13.4 h	11 h 24 m	64-78 / 76-88%	Warm wet phase	7	Late nests; incubation; female recovery
August	29-32 C	26-27 C	44-48 C	4-6	12.9 h	10 h 54 m	64-80 / 78-90%	Warm; storm rain pulses	7	Incubation
September	29-31 C	25-27 C	43-47 C	4-6	12.3 h	10 h 18 m	68-82 / 80-92%	Wet / storm season	7	Late incubation; hatching begins late month
October	28-30 C	24-26 C	43-47 C	4-6	11.7 h	9 h 42 m	66-80 / 78-90%	Wet phase easing	6-7	Main hatchling emergence / growth
November	27-29 C	23-25 C	42-46 C	4-6	11.1 h	9 h 6 m	60-74 / 72-84%	Rain reduces	6	Transition to dry season
December	25-28 C	21-23 C	42-46 C	4-6	10.7 h	8 h 42 m	56-70 / 70-82%	Dry phase; light AM mist	5-6	Seasonal reset; no brumation

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

Taxonomy and range

Cyclura cychlura inornata is the Allen Cays / northern Exuma subspecies of C. cychlura. Preserve exact cay provenance and pedigree.

Heat and UVB

Use a strong gradient with a broad 42-48 C basking-surface working target and UVI 4-6 at the main basking zone, plus immediate deep shade.

Rainfall

Reproduce a drier November-April period and wetter May-October period without chronic dehydration; retain humid retreats and drinking water.

Diet

Primarily herbivorous: diverse calcium-rich leaves, browse, flowers and fibrous vegetables with modest fruit. Avoid animal protein and tourist foods.

Breeding

Mating occurs early to mid-May. Females migrate to nest sites in mid to late June; completed nests occur from mid-June into mid-July.

Nesting

Published burrows average about 149 cm long and chambers about 28 cm deep at about 31.4 C. Provide very deep, compactable nesting substrate.

Clutch / frequency

Clutches contain 1-10 eggs (mean 4.6). Only about one in three adult females nests each year, although the largest females usually nest annually.

Hatching

Natural hatching is generally late September to early October after roughly 80-85 days. Avoid overheating eggs and document all artificial-incubation variables.