Species keeper protocol

Cyclura rileyi cristata

White Cay Rock Iguana / Sandy Cay Rock Iguana
A Critically Endangered Bahamian rock iguana naturally known from White/Sandy Cay. Keep intense basking and UV, broad thermal choice, a plant-dominant diet, a drier winter/early-spring phase and a deep nest zone. Published cristata reproductive data are sparse, so provisional dates and incubation values are explicitly labelled as extrapolations.

Day air28-30 CSeasonal ambient target with cooler retreats

Basking surface42-46 CBroad local basking zone; not whole-enclosure air

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

SeasonPossible hatch period by C. rileyi analogyProbable mating May-June; probable laying June-July - both provisional

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

Possible hatch period by C. rileyi analogy

White (= Sandy) Cay, southern Exumas, The Bahamas - exposed maritime scrub and limestone cay habitat

28-30 CDay air

23-25 CNight

42-46 CBasking

4-6T5 UVI*

11.7 hPhotoperiod

9 h 42 mT5 UVB duration

65-80 / 78-89%RH day / night*

Peak rainfall / stormsRain / mist

6Food 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	21-23 C	41-45 C	4-6	10.9 h	8 h 54 m	58-70 / 72-82%	Dry-season maintenance; light AM mist 2-3x/wk	5	Cooler, drier phase; keep adults lean
February	25-27 C	21-23 C	41-45 C	4-6	11.4 h	9 h 24 m	57-69 / 72-82%	Dry; localized moist refuge only	5	Dry-season conditioning; broad browse variety
March	25-28 C	21-23 C	42-46 C	4-6	12.0 h	10 h	56-69 / 72-82%	Driest period; avoid chronic enclosure wetness	5	Seasonal warm-up; no brumation
April	26-29 C	22-24 C	42-46 C	4-6	12.7 h	10 h 42 m	58-72 / 74-84%	Dry-to-wet transition	5-6	Increase feeding quality; prepare nest zone
May	27-30 C	23-25 C	43-47 C	4-6	13.2 h	11 h 12 m	62-76 / 76-86%	Rain pulses increase	6	Probable courtship/mating - evidence indirect
June	28-31 C	24-26 C	43-47 C	4-6	13.5 h	11 h 30 m	64-78 / 78-88%	Warm; regular rain pulses	6-7	Probable mating / gravid period
July	29-31 C	24-26 C	43-47 C	4-6	13.3 h	11 h 18 m	65-80 / 78-89%	Warm wet season; moderate rain	6-7	Probable oviposition window; monitor digging
August	29-31 C	24-26 C	43-47 C	4-6	12.9 h	10 h 54 m	66-80 / 79-90%	Wet/storm season	6	Female recovery / possible incubation
September	29-31 C	24-26 C	42-46 C	4-6	12.2 h	10 h 12 m	66-81 / 79-90%	Wet/storm season	6	Possible late incubation; maintain stable moisture
October	28-30 C	23-25 C	42-46 C	4-6	11.7 h	9 h 42 m	65-80 / 78-89%	Peak rainfall / storms	6	Possible hatch period by C. rileyi analogy
November	27-29 C	22-24 C	41-45 C	4-6	11.1 h	9 h 6 m	62-76 / 75-86%	Rainfall easing	5-6	Juvenile growth; transition toward dry phase
December	26-28 C	21-23 C	41-45 C	4-6	10.8 h	8 h 48 m	59-72 / 73-84%	Drier transition	5	Seasonal reset; reduce rain, not drinking water

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

Habitat

Known naturally from White (= Sandy) Cay in the extreme southern Exumas, The Bahamas; exposed maritime scrub and limestone cay habitat.

Heat and UVB

Use a broad 41-47 C basking-surface working target and UVI 4-6 at the main basking area, with cooler air and immediate deep shade.

Diet

The IUCN husbandry manual describes C. r. cristata as primarily herbivorous. Prioritize calcium-rich browse, leafy weeds, flowers, fibrous vegetables and cactus.

Breeding

Direct reproductive data are sparse. The IUCN manual suggests mating probably May-June and oviposition probably June-July.

Nesting

Natural cristata nest dimensions and clutch size remain undocumented in the standard husbandry manual. Provide a large deep compactable nest zone and log every event.

Incubation

Cristata-specific incubation temperature and duration are unknown. 29.5-30.5 C and an 85-92 day monitoring window are conservative extrapolations from related Cyclura, not proven optima.

Status

Cyclura rileyi cristata is listed as Critically Endangered by the IUCN SSC Iguana Specialist Group; Cyclura rileyi is CITES Appendix I.