Pasteur’s Day Gecko (*Phelsuma pasteuri)

Pasteur’s Day Gecko (Phelsuma pasteuri) Care Sheet

Pasteur’s Day Gecko (Phelsuma pasteuri) is a small, colourful diurnal gecko endemic to Mayotte in the Comoros archipelago of the Indian Ocean.

Adults are predominantly green, often displaying attractive turquoise or blue tones together with red markings. Although considerably smaller than giant day geckos, they are highly active animals that make extensive use of vertical space.

Like other members of the genus Phelsuma, Pasteur’s Day Geckos are strongly arboreal. They spend much of the day climbing vegetation, basking, hunting small invertebrates and feeding on nectar and other sugary plant resources.

Their daytime activity makes appropriate UVB, bright visible lighting and access to a localised basking area fundamental components of successful captive husbandry.

Pasteur’s Day Geckos are extremely quick and possess delicate skin. They should therefore be considered primarily display reptiles rather than animals intended for routine handling.

Successful husbandry centres on a secure vertical enclosure, abundant fine climbing structure, appropriate UVB, bright visible lighting, a localised basking area, warm ambient conditions, fluctuating humidity, excellent ventilation and a varied omnivorous diet.

Quick Facts

Scientific name: Phelsuma pasteuri
Common name: Pasteur’s Day Gecko
Family: Gekkonidae
Native range: Mayotte, Comoros archipelago
Lifestyle: Arboreal
Activity: Diurnal
Adult length: Approximately 4–5 inches including the tail
Lifespan: Approximately 8–12+ years with excellent care
Experience level: Intermediate
Diet: Omnivorous
Temperament: Alert, extremely fast and potentially territorial
Adult enclosure: Approximately 18" × 18" × 24" minimum for one adult; larger preferred
Basking area: Approximately 29–32°C
General daytime temperature: Approximately 24–27°C
Cool area: Approximately 21–24°C
Night temperature: Approximately 19–22°C
Humidity: Approximately 60–80% with regular drying periods
UVB: Essential
Handling: Not recommended except when necessary
Social housing: Individual housing safest

Natural Distribution

Phelsuma pasteuri is native to Mayotte, part of the Comoros archipelago between Madagascar and the African mainland.

Its restricted natural distribution makes responsible captive breeding particularly valuable.

Island reptiles with limited ranges can be vulnerable to environmental pressures including:

  • Habitat alteration
  • Introduced predators
  • Invasive species
  • Environmental change

Captive-bred animals of documented origin should be strongly preferred.

Natural Habitat

Pasteur’s Day Geckos inhabit warm, humid and vegetated environments.

They utilise:

  • Trees
  • Shrubs
  • Palms
  • Broad-leaved vegetation
  • Vertical stems
  • Vegetated areas around human habitation

They spend most of their lives above ground.

Captive accommodation should therefore provide abundant usable vertical structure.

Appearance

Pasteur’s Day Geckos are predominantly green.

Depending on the individual, colouration may include:

  • Bright green
  • Blue-green
  • Turquoise
  • Red
  • Yellow
  • Black

Red markings may be present across the head and dorsal surface.

Colour Variation

Colour intensity can change according to:

  • Temperature
  • Lighting
  • Activity
  • Stress
  • Reproductive condition
  • Health

Temporary changes in colour are normal.

Bright, appropriate visible lighting allows natural colouration to be displayed effectively.

Adult Size

Adults generally reach approximately:

4–5 inches total length

including the tail.

Although small, they are highly active and should not be maintained in unnecessarily small accommodation.

Behaviour

Pasteur’s Day Geckos are strongly active during daylight.

Normal behaviour includes:

  • Basking
  • Climbing
  • Hunting small insects
  • Exploring vegetation
  • Territorial displays
  • Feeding on nectar-like foods
  • Drinking droplets
  • Moving between exposed and shaded areas

They are highly visual and react rapidly to movement.

Temperament

These geckos are generally nervous rather than aggressive towards people.

They are:

  • Extremely fast
  • Agile
  • Excellent climbers
  • Capable of sudden jumps

They are best maintained as display animals.

Handling

Routine handling is not recommended.

When an animal must be moved, guiding it carefully into a secure container is generally preferable to physically restraining it.

Never:

  • Grab the tail
  • Squeeze the body
  • Restrain loose skin
  • Chase the gecko repeatedly
  • Handle it in an unsecured room

Delicate Skin

Like other Phelsuma, Pasteur’s Day Geckos possess delicate skin.

Rough restraint can cause sections of skin to tear away.

This defensive adaptation is an important reason to minimise unnecessary handling.

Tail Loss

The tail can also be shed if the gecko is severely stressed or improperly restrained.

Never lift or restrain the animal by its tail.

A regenerated tail may differ noticeably from the original.

Enclosure Size

For a single adult:

18" × 18" × 24"

should be considered a practical minimum.

Larger accommodation is preferred where possible.

Additional space allows:

  • Greater exercise
  • More climbing opportunities
  • Better thermal gradients
  • Better UV gradients
  • Denser planting
  • Greater behavioural choice

Vertical Space

Vertical space is particularly important.

The enclosure should contain usable climbing structure throughout its height.

A tall but empty enclosure does not provide suitable arboreal habitat.

Climbing Structure

Suitable furnishings include:

  • Bamboo
  • Fine natural branches
  • Cork
  • Vines
  • Live plants
  • Artificial foliage

Arrange climbing routes:

  • Vertically
  • Horizontally
  • Diagonally

A mixture of different branch diameters is beneficial.

Bamboo

Bamboo is particularly useful for day geckos.

It provides:

  • Smooth climbing surfaces
  • Basking sites
  • Resting areas
  • Visual barriers

All bamboo should be securely positioned.

Foliage

Dense foliage provides:

  • Security
  • Shade
  • Drinking surfaces
  • Climbing opportunities
  • Humidity gradients
  • Visual barriers

Suitable reptile-safe plants may include:

  • Pothos
  • Ficus
  • Schefflera
  • Bromeliads
  • Other suitable tropical plants

Ensure all plants are free from pesticides and harmful chemicals.

Hides

Provide elevated cover using:

  • Dense vegetation
  • Cork
  • Hollow bamboo
  • Concealed areas behind plants

The gecko should always have the opportunity to move completely out of sight.

Enclosure Security

Escape prevention is critical.

Pasteur’s Day Geckos can exploit extremely small gaps.

Check carefully around:

  • Doors
  • Sliding tracks
  • Ventilation
  • Cable ports
  • Lid fittings

before introducing the animal.

Ventilation Mesh

Ventilation mesh must be sufficiently fine to prevent escape while still allowing good airflow.

Small feeder insects may also escape through coarse mesh.

Substrate

Suitable substrates include:

  • Organic topsoil
  • Coco fibre
  • Tropical soil mixtures
  • Orchid bark
  • Leaf litter

The substrate should retain some moisture while allowing effective drainage.

Bioactive Housing

Pasteur’s Day Geckos are well suited to naturalistic bioactive enclosures.

A properly established system may contain:

  • Live plants
  • Natural soil
  • Leaf litter
  • Springtails
  • Suitable small isopods

Bioactive housing does not eliminate the need for routine maintenance and health monitoring.

Temperature Gradient

Provide a clear thermal gradient.

The entire enclosure should never be maintained at basking temperature.

Basking Temperature

Provide a localised basking area around:

29–32°C

The gecko must be able to move away easily.

General Day Temperature

Most of the enclosure can remain around:

24–27°C

Cool Area

Provide cooler shaded areas around:

21–24°C

Night Temperature

Night temperatures can generally fall to approximately:

19–22°C

A modest nighttime reduction is appropriate.

Overheating

Small arboreal enclosures can heat rapidly.

Avoid prolonged excessive temperatures and take particular care during summer heatwaves.

Cooler shaded retreats must always remain available.

Heating

Where supplemental heating is required, use suitable overhead heating to create a localised basking area.

Heating equipment should be safely controlled and monitored.

UVB

UVB is essential.

Pasteur’s Day Geckos are strongly diurnal and naturally exposed to daylight.

Appropriate UVB supports:

  • Vitamin D3 synthesis
  • Calcium metabolism
  • Healthy skeletal development
  • Natural basking behaviour

UV Gradient

The enclosure should provide:

  • Appropriate UV exposure around basking areas
  • Moderate exposure
  • Filtered exposure
  • Complete shade

The gecko must be able to regulate its exposure behaviourally.

UVB Placement

UVB effectiveness depends on:

  • Lamp output
  • Distance
  • Mesh obstruction
  • Reflector
  • Enclosure design

Follow current manufacturer recommendations when selecting and positioning UVB equipment.

Visible Lighting

Bright visible lighting is extremely important.

These are active daytime reptiles.

Good lighting encourages:

  • Natural activity
  • Feeding
  • Basking
  • Colour display
  • Plant growth

Suitable daylight LED lighting can be used alongside UVB and basking equipment.

Photoperiod

Approximately:

11–13 hours of daylight

is suitable depending on season.

Night Lighting

The enclosure should become dark at night.

Do not leave visible red, blue or purple lamps operating throughout the night.

Humidity

General humidity around:

60–80%

is appropriate.

Humidity should fluctuate rather than remain constantly high.

Humidity Cycle

Humidity will normally increase following misting before gradually falling as ventilation dries the enclosure.

This daily fluctuation is desirable.

The enclosure should not remain permanently saturated.

Misting

Light misting:

Once or twice daily

works well in many setups.

Frequency depends on:

  • Ventilation
  • Planting
  • Substrate
  • Room humidity
  • Season

Allow surfaces to partially dry between misting sessions.

Hydration

Pasteur’s Day Geckos frequently drink droplets from:

  • Leaves
  • Glass
  • Bamboo
  • Branches

Regular misting therefore provides important drinking opportunities.

Water Bowl

A small shallow water dish can also be provided.

Keep it clean and replace the water regularly.

Ventilation

Excellent ventilation is essential.

High humidity combined with stagnant conditions can encourage:

  • Mould
  • Bacterial growth
  • Skin problems
  • Respiratory disease

The enclosure should remain humid but fresh.

Diet

Pasteur’s Day Geckos are omnivorous.

Their captive diet should include:

  • Appropriately sized live insects
  • Suitable nutritionally complete gecko diet

Dietary variety is important.

Live Insects

Suitable feeders include:

  • Small crickets
  • Small roach nymphs
  • Fruit flies
  • Small black soldier fly larvae
  • Other appropriately sized captive-produced insects

Avoid excessively large prey.

Gut Loading

Feeder insects should be properly gut-loaded before use.

Suitable gut-loading foods include:

  • Leafy greens
  • Vegetables
  • Appropriate commercial gut-loading products

Calcium Supplementation

Live insects should be appropriately dusted with calcium.

Requirements depend on:

  • Age
  • UVB provision
  • Overall diet
  • Reproductive status

Growing juveniles and breeding females require particularly careful calcium management.

Multivitamins

A suitable reptile multivitamin can be offered periodically.

Avoid excessive supplementation.

Complete Gecko Diet

A nutritionally complete commercial gecko diet can provide the fruit and nectar-like component of the captive diet.

Prepare according to manufacturer instructions.

Offer small fresh portions and remove uneaten food before it spoils.

Fresh Fruit

Small quantities of suitable soft fruit may occasionally be offered as enrichment.

Fresh fruit should not replace a nutritionally complete gecko diet.

Feeding Frequency

Juveniles can generally be offered food:

Daily or almost daily

Adults can generally be fed:

4–5 times per week

using a varied combination of live insects and complete gecko diet.

Adjust feeding according to:

  • Body condition
  • Activity
  • Reproductive status

Feeding Ledges

Elevated feeding stations are useful.

These allow natural arboreal feeding without requiring the gecko to descend to the enclosure floor.

Food Enrichment

Encourage natural feeding behaviour by:

  • Offering live insects
  • Varying feeding locations
  • Using elevated feeding stations
  • Allowing controlled hunting among vegetation

Social Housing

Individual housing is the safest general recommendation.

Pasteur’s Day Geckos can be territorial.

Adult Males

Adult males should not be housed together.

Territorial aggression can result in:

  • Bite injuries
  • Chronic stress
  • Feeding suppression
  • Restricted basking access

Male/Female Housing

Experienced breeders may maintain compatible male/female pairs in sufficiently large, densely furnished enclosures.

Females must be monitored carefully for:

  • Persistent courtship
  • Mating injuries
  • Stress
  • Feeding competition

Separate accommodation should always be available.

Female Aggression

Females may also display territorial behaviour.

Do not assume females will automatically coexist peacefully.

Sexing

Mature males generally develop:

  • More pronounced preanal/femoral pores
  • Broader tail base
  • More obvious reproductive structures

Sexing juveniles can be considerably more difficult.

Breeding

Pasteur’s Day Geckos can be bred successfully in captivity.

Only healthy mature animals in excellent condition should be bred.

Responsible captive breeding is particularly valuable for species with restricted natural distributions.

Female Condition

Breeding females require excellent:

  • Nutrition
  • Calcium provision
  • UVB
  • Hydration
  • Body condition

Repeated egg production can place substantial demands on a small female.

Egg Laying

Females generally produce:

2 eggs per clutch

although single eggs can occasionally occur.

Multiple clutches may be produced during a breeding season.

Egg Deposition

Females seek protected locations for egg deposition.

Potential sites include:

  • Bamboo
  • Cork
  • Plant structures
  • Concealed enclosure furnishings

Do not forcibly disturb eggs that cannot be safely removed.

Incubation

Eggs can generally be incubated around:

24–27°C

under stable conditions.

Incubation commonly lasts approximately:

45–70+ days

depending on temperature and other factors.

Avoid excessive incubation temperatures.

Eggs should not be rotated after laying.

Hatchlings

Hatchlings are extremely small and fast.

Provide:

  • Secure escape-proof accommodation
  • Fine climbing structures
  • Dense foliage
  • Appropriate UVB
  • Moderate basking temperatures
  • Regular misting
  • Tiny live prey
  • Suitable complete gecko diet
  • Appropriate supplementation

Hatchling Food

Suitable prey may include:

  • Flightless fruit flies
  • Pinhead crickets
  • Tiny roach nymphs
  • Other appropriately sized captive-produced feeders

Hatchling Security

Escape prevention is critical.

Hatchlings can exploit extremely small gaps around:

  • Doors
  • Ventilation
  • Cable ports
  • Sliding tracks
  • Lid fittings

Check housing carefully before introducing young geckos.

Quarantine

All newly acquired reptiles should undergo quarantine.

A minimum of approximately:

90 days

is a sensible starting point.

Monitor:

  • Feeding
  • Weight
  • Faeces
  • Skin
  • Shedding
  • Respiration
  • Activity

Shedding

Healthy Pasteur’s Day Geckos generally shed successfully when correctly hydrated.

Retained shed may occasionally occur around:

  • Toes
  • Tail
  • Limbs

Avoid forcibly pulling firmly attached skin.

Toe Health

Healthy adhesive toe pads are essential for normal climbing.

Retained shed or contamination can interfere with grip.

Inspect the feet periodically.

Signs of Good Health

A healthy Pasteur’s Day Gecko should generally display:

  • Clear bright eyes
  • Strong grip
  • Alert daytime activity
  • Regular basking
  • Active hunting
  • Appropriate body condition
  • Smooth coordinated climbing
  • Healthy skin
  • Normal faeces

Warning Signs

Seek veterinary advice for:

  • Persistent food refusal
  • Unexplained weight loss
  • Weak grip
  • Tremors
  • Soft jaw
  • Swollen limbs
  • Respiratory symptoms
  • Persistent diarrhoea
  • Severe retained shed
  • Skin lesions
  • Significant lethargy

Common Husbandry Mistakes

Inadequate UVB

These are strongly diurnal reptiles and require appropriate UVB.

Poor Visible Lighting

Bright daytime illumination is important for natural activity and behaviour.

Enclosure Too Bare

They require abundant bamboo, branches and vegetation.

Keeping the Entire Enclosure Too Hot

Provide a localised basking area alongside cooler shaded retreats.

Constantly Wet Conditions

Humidity should fluctuate and enclosure surfaces should partially dry.

Poor Ventilation

High humidity must be combined with effective airflow.

Feeding Only Fruit

A balanced diet requires appropriate live prey, calcium, vitamins and minerals.

Feeder Insects Too Large

These are small geckos and require appropriately sized prey.

Housing Adult Males Together

Territorial aggression can result in serious injury.

Excessive Handling

Their speed and delicate skin make them unsuitable for routine handling.

Insecure Enclosure

Even tiny gaps can result in an escaped gecko.

Captive-Bred Animals

Captive-bred Pasteur’s Day Geckos should be strongly preferred.

Advantages include:

  • Known origin
  • Established feeding
  • Better adaptation to captive conditions
  • Reduced parasite concerns
  • Reduced collection pressure on wild populations

Responsible captive breeding and accurate record keeping help maintain sustainable captive populations.

Responsible Ownership

Before acquiring a Pasteur’s Day Gecko, ensure you can provide:

  • A secure vertical enclosure
  • Extensive fine climbing structure
  • Dense foliage
  • Appropriate UVB
  • Bright visible lighting
  • A localised basking area
  • Cooler shaded retreats
  • High but fluctuating humidity
  • Excellent ventilation
  • Regular misting
  • Appropriately sized live insects
  • Complete gecko diet
  • Appropriate supplementation
  • Long-term veterinary care

Suitability

Advantages

  • Attractive green, turquoise and red colouration
  • Highly active during daylight
  • Small adult size
  • Fascinating arboreal behaviour
  • Excellent planted-display species
  • Captive breeding achievable
  • Well suited to naturalistic enclosures

Considerations

  • Extremely fast
  • Delicate skin
  • Not suitable for routine handling
  • Escape-proof housing essential
  • UVB required
  • Bright visible lighting required
  • Requires small live feeder insects
  • Territorial behaviour
  • Careful humidity management required

Summary

Pasteur’s Day Gecko (Phelsuma pasteuri) is a small, colourful and highly active day gecko from Mayotte that is ideally suited to a well-planted vertical display enclosure.

Successful husbandry centres on:

  • Approximately 18" × 18" × 24" minimum adult accommodation
  • Larger accommodation preferred where possible
  • Extensive bamboo, branches and fine climbing routes
  • Dense foliage and elevated cover
  • A localised basking area around 29–32°C
  • General daytime temperatures around 24–27°C
  • Cooler shaded areas around 21–24°C
  • Appropriate nighttime cooling
  • Strong appropriate UVB
  • Bright visible daytime lighting
  • Approximately 60–80% humidity with regular drying periods
  • Excellent ventilation
  • Regular misting
  • Appropriately sized gut-loaded live insects
  • Suitable complete gecko diet
  • Appropriate calcium supplementation
  • Minimal unnecessary handling
  • Individual housing as the safest default

When provided with appropriate UVB, bright lighting, abundant climbing structure, correct nutrition and carefully managed humidity, captive-bred Pasteur’s Day Geckos can make exceptionally attractive and engaging display reptiles.


IMPORTANT INFORMATION:

This care sheet provides general husbandry guidance and does not replace species-specific research or veterinary advice. Individual requirements may vary.

Always check current legislation governing the acquisition, collection, import, transport, keeping, breeding or sale of reptiles in your jurisdiction.

If you have concerns about an animal’s health or care, consult a suitably experienced exotic or reptile veterinarian.

Information correct at the date of publication.

reptilecommunity.com | Revised: August 2026