The goal of this website is to promote the continued existence of Mountain Tortoises, Manouria emys through conservation in the wild and preservation in captivity by responsible stewards.
A father son team created this website in early 2020 based on a personal appreciation for this species, direct experience, cited publications, and input from experienced individuals at private and nonprofit instituions.
A special thanks to all those that have contributed.
Select pictures to see additional images.
Manouria emys are a species of tortoise with several common names including: Giant Forest Tortoise, Asian Forest Tortoise, Giant Asian Tortoise, Six-Legged Tortoise, Elephant Turtle, and Burmese Mountain Tortoise. The two subspecies are commonly called Black Mountain Tortoise and Brown Mountain Tortoise.
In reality, Burma is now Mayanmar, they live in multiple countries, don’t have six legs just a couple large spurs, share the distinction of being a giant forest tortoise with other species, and both subspecies are shades of brown. We recommend using the following:
Manouria emys phayrei Northern Mountain Tortoise
Sometimes called the Black subspecies
Northern Thailand, Myanmar, Bangladesh, and the eastern edge of India
Larger: Carapace length up to 24in (62cm)
Commonly lay ~60 eggs in a single clutch in April; can be as late at July
Largest reported clutch had 74 eggs
At least one pectoral scute usually reaches the centerline of the plastron.
Manouria emys emys Southern Mountain Tortoise
Sometimes called the Brown subspecies
Southern Thailand, Malaysia, Sumatra, and Borneo
Carapace length up to 22 inches (56cm); usually smaller
Normally lay ~40 eggs in a single clutch between May and August
Largest reported clutch had 53 eggs
Potentially less cold tolerant
Pectoral scutes usually do NOT reach the centerline of the plastron
In The Wild
Based on listed references, this chart shows where there is evidence of Manouria emys living.
Spanning several countries and thousands of miles their range follows coastal mountain ranges collecting the warm humid air off the Indian ocean. Manouria emys phayrei live in the North part of the range and Manouria emys emys in the Southern parts.
The extent of integration in the middle between the two subspecies is unknown. After years collection by hunters and habitat loss, they are rare to absent from many parts of their range; especially in the North.
Located on tropical costal mountains 2000-5000 feet above sea-level they receive warm moist air blowing off the Indian Ocean during the wet season and cool air from the North during the dry season.
Extremes are buffered in most of their range to the South with tropical average lows ~72F and highs ~89F throughout the year.
The table to the right allows you to compare cities across their range with your home town.
Based on average lows below 40F at the North end of their natural range, its likely they occasionally encounter freezing temperatures in the wild.
Manouria emys commonly overwinter buried under mulch and leafs or inside a tortoise hut in the US along the gulf coast. They are one of the most cold tolerant giant tortoise.
High humidity from 70-100% is common for much of the year.
Based on the field research in our reference section, Manouria emys use their environment to thermoregulate for an optimal body temperature of ~70 F° (21 C°). When cool they bask; when too warm they move to shade, soak, or bury themself. While basking they maximize their exposure by positioning their shell at a right angle to the sun with their legs stretched out. Some people report that they will purposefully select overnight locations where the sun will hit in the morning to warm them up.
Manouria emys take advantage of multiple microhabitats. Over the course of a year, the home range of an adult is around a quarter mile (0.5 km)2.
Young animals travel much less.
Streams and pools
Seasons are most pronounced in the Northern parts of their range where the following is typical.
Cool-Dry Season (Nov-Feb): Spend the most time buried under leaves and logs.
Warmup Season (Mar-Apr): Spend the most time either soaking in shaded streams and swamps, or nesting.
Warm Wet Season (May-Oct): Adults spend the most time feeding in bamboo forests and Young spend the most time in swamps and streams.
Manouria emys are known to eat a wide variety of items in the wild. Some of their favorites include.
Fresh Bamboo Shoots: Bambusa sp. especially during wet season.
Elephant Ears: Alocasia sp. considered poisonous to most animals but loved by Manouria emys. Pictures of captive Manouria eating Alocasia sp.
Mushrooms/Fungi: Many types trigger a strong feeding response.
Elastostema sp. - Major item in dry season
Banana plants: Musa sp. - Major item for Juveniles in dry season
Zingiber sp. - Major item for Juveniles in dry season
Amorphophallus paeoniifolius - Adults
Phrynium pubinerve - Major item for Juveniles in dry season
Amischotolype monosperma - flower, stem, and leaves - Juveniles
Lasia spinosa - Major item for juveniles
Fallen fruits: Eaten opportunistically
Animal matter: Eaten opportunistically based on captive observations
Manouria emys, especially Manouria emys phayrei, are under tremendous pressure in their native range from habitat loss, subsistence collection, and intensive commercial exploitation for black markets. Half of their habitat has been lost or degraded through the encroachment of human activity. Unless in a protected area, large reproducing adults are rarely encountered.
Small home ranges and the need for multiple microhabitats makes Manouria emys more vulnerable to habitat degradation and fragmentation. Their long lives can mask the reality of remaining habitat lacking the ability to sustain their full life cycle. Fragmented populations may not provide enough genetic variability to support the continued health of future generations of this species without human intervention.
Manouria emys are listed as critically endangered by multiple organizations including IUCN Redlist. Legal protections exist to prevent collection from the wild but with limited resources, enforcement is difficult. Conservation organizations including the Turtle Survival Alliance are working with several local communities and zoos to run breeding and head start programs in their native range. To preserve Manouria emys from extinction, assurance colonies exist across countries, zoos, non-profits, and private individuals.
We encourage all activities that promote the abundant appreciation and existence of Manouria emys through quality education, conservation, and preservation. Most important, this includes protection of this species and their habitat in the wild including advocacy in their native range, in-situ breeding, and head start programs. Secondly, it includes, science based research, genetics management, and long term assurance populations in captivity with responsible organizations and individuals. There are many ways to get involved. Here are a few organizations we recommend supporting based on their support of Manouria emys conservation and preservation.
One easy way to contribute is by using Amazon Smile where Amazon pays a non-profit of your choice 0.5% of your purchases at no cost to you: smile.amazon.com
In addition to participating in a US based breeding program, the TSA is successfully working on in-situ breeding, headstart, and release programs with local communities in three native countries. The following slideshow highlight four Manouria emys phayrei breeding programs.
When kept outside in warm humid areas, Manouria emys are one of the easiest and most rewarding tortoises to care for. They're extremely friendly and interactive; don't dig holes like sulcata; eat just about anything; are less likely to get shell deformities; and may be the most cold tolerant giant tortoise. They get big enough to fend off small predators but not too big to move when needed.
Through captive breeding, hundreds are hatched in the US each year. Unfortunately, similar to other types of tortoises, many don't survive their first year of life. To increase survival rates, we recommend breeders and experienced individuals head start Manouria emys and people new to caring for tortoises avoid acquiring animals less than a year old.
The following captive care tips are based on decades of experience from several successful stewards.
Provide access to food every day with larger feedings every couple days.
High fiber and the act of grazing are key for good health and strength.
Grass, weeds, and local foliage are the best foods for tortoises.
Plant and harvest: Grasses, spineless cactus pads, bamboo shoots, banana plants, elephant ears, mushrooms, and the leaves and flowers from hibiscus, rose mallow, rose of sharon, fig, mulberry, dandelions, clover, etc.
Mushrooms, elephant ears, and bamboo shoots trigger feeding for Manouria. All of them are easy to grow and produce a lot of food. Seeding Wine Cap Mushrooms Stropharia rugoso-annulata in mulch can produce food for years.
Elephant ears are poisious to most animals but Manouria love them in the wild and captivity as part of a balanced diet.
Provide a weekly dose of Mazuri tortoise chow and calcium supplementation.
Store bought produce in moderation: Mustard greens, endive, sweet potatoes, sweet peppers, carrots, squash, zucchini, green beans, etc. Avoid calcium-binding oxalates found in spinach, broccoli, etc.
Keep fruits and berries to a minimum. The fiberous skins, peals, and rinds are better than the fruit.
Coming from a cloud forest, hydration is very important for Manouria.
Poor hydration is a leading cause of hatchling death. Spray enclosures daily and soak young animals every few days.
Plant saucers make good soak stations and chicken waterers can provide clean water over longer periods.
Large Manouria will wade and swim in flat water, even deep water. They also wallow in mud to cool off in summer. Any and all water features are greatly appreciated in large enclosures.
They benefit from having access to shade under multiple canopy layers. This means having high canopy shade in addition to lower canopy levels to sandwiching air of decreasing temperatures and increasing humidity.
When provided a thick layer of moist loose leaves / mulch, Manouria will bury themselves at night and during mid-day heat to maintain healthy hydration.
When possible, keep Manouria emys outside in a natural setting. Don't leave unprotected if the temperature drops below 40F, especially if wet and not offset by warmer temperatures the next day
Provide access to all the micro habitats tortoises need to regulate their temperature and hydration including full shade, sun, a soaking area, a moist hide, and a dry hide as seasonally appropriete.
There is hierarchy across Manouria emys, often based on size. Use of an area by a dominate animal can make that space unavailable to smaller animals. Simply bringing everyone to the food can break down some issues. Providing separate enclosures or redundant micro habitats is sometimes needed.
Create foraging-grazing opportunities by planting lots of edible vegetation.
Build solid sides and multiple multiple hides for a sense of security and protection from extreme weather.
Strong legs help males breed and females nest. Safely placed rocks, logs, and corkbard can provide some elevation for exercise; having an actual hill to climb is even better.
Small Tortoise Considerations
Many animals including cats, dogs, opossums, rats, raptors, and especially raccoons are known to kill small to medium size tortoises.
Left over food scraps can attract these animals; especially at night.
For piece of mind without reducing the many benefits of keeping tortoises outside, we recommend completely surrounding enclosures in steel mesh and J Clips with holes no larger than 1"x1" (2cm x 2cm).
Solid walls around the inside perimeter keep tortoises from seeing through or contacting the mesh.
Ensure smaller tortoises in a group get enought food and don't get stressed by more aggressive individuals.
Provide several hides and a deep moist mix of bio-active mulch and leaves for tortoise to bury themselves.
Springtails and isopods are a good addition to clean up food scrapes and waste.
Large Tortoise Considerations:
Provide as large of an enclosure as possible with 24” solid smooth walls to prevent escapes; Planted with lush vegetation and forage.
Provide piles of moist leafs, mulch to bury themself or build nests in shaded locations.
Depending on your location, an insulated tortoise shed for weather extremes may be useful.
A pond for hydration, cooling, and escape from insects will also be much appreciated.
Consider positioning the habitat in full view from a part of your home you spend a lot of time in, to enjoy their daily routine and to keep an eye on things.
Keep track of the genetics of your animals; know where they came from; uniquely id through pictures, physical markers such as numbers, and/or pit tags injected by a vet.
If you believe you have a Manouria emys in the US with a unique bloodline that is not represented in the Species Survival Program, SSP studbook, we can help connect you with the coordinator.
Record your animal's weight and length on a periodic basis to spot health issues and generally understand what’s going on. Sometimes animals will stop feeding when stressed by other animals in the same enclosure.
Consider implementing video cameras for security and to keep an eye on things.
Find the best tortoise vets in your area before you need them.
Determining sex is difficult, especially with sub-adults. To be 100% sure, observe either a penile display or eggs.
Internal scoping by a vet with a lot of chelonian experience can also be valid but comes with the risk of harming the animal and expense.
Everything else below is directional guidance.
Mates with females
Displays male dominence
Mature males are smaller than mature females
Wider longer tail that extends past large spurs on either side
Fifth vertebral scute sharply sloped instead of in line with the natural slope of the shell
Carapace more narrow
Males court and mate with
Builds a nest
Larger than mature males, >18in
Smaller shorter tail that does not extend past large spurs on either side
Smooth slope line down back of shell
Comparativly wider and fuller carapace
Some male Manouria emys have a natural drive and others need motivation. For the later, introduce a smaller male as a sparring partner in the female’s enclosure. Supervise sparing which can end with the smaller animal being flipped over. After sparing, remove the defeated male. Allow time for breeding and remove breeder male before nesting.
Before mating, and in other situations, they will bob their heads up and down while vocalizing as shown in video here. They often bob heads and circle each other in a tortoise dance before mating.
Manouria emys display some of the most interesting and communicative mating and nesting behaviors across chelonians.
It takes 10-15 years for Manouria emys to become sexually mature.
Young females often go through the motions, dropping only a couple eggs as they initially mature.
Fertility and egg clutch size increase with age and size.
Females may grow more slowly or stop growing when they’re producing eggs. Some of the largest females havn’t mated until later in life allowing them to put on more size.
Mature female Manouria emysnest up to once a year, usually a couple months before the monsoon / wet season so hatchlings will have plenty of food and moisture to get a head start on life.
On average, Manouria emys phayreinest a couple months earlier than Manouria emys emy staring in April. This could be to give hatchlings more time to mature before winter which their Southern relatives don't experience.
Females spend days to weeks pulling and stomping down mulch and leaves into a large pile up to two feet tall. Sometimes they stick their head into the compost and seem to measure the moisture and temperature levels. If too dry, she may add moisture through urination.
Provide lots of nesting material and space for nesting months before needed.
Once a satisfactory nest has been constructed, females digs a hole in the top of the nest, and deposits and buries as many as ~80 eggs. Less primative tortoises lay eggs with hard shells like chickens but Manouria emys lay soft leathery eggs that often have dimples.
The top of the nest is often covered with green foilage, likely to hide the smell and sight of the nest. Unique to chelonians, the mother sits on top of the nest guarding from predators.
Other tortoise species have generated fertile eggs for years after being separated from males through sperm retention. This should be a consideration when managing pairings for genetics.
Stressed females can reabsorb eggs instead of laying them. This has been seen after moving females to new locations and also when housed with larger more dominate animals. On one occasion, a smaller gravid Manouria emys emys used another tortoise's shell to gain enough height to escape her stressful situation and laid in the woods close by.
There have also been observations of female Manouria emys phayrei collaborating to build and lay in the same nest. On one occasion, the females started building nests on opposite sides of the yard, than each visited the other's location, spent some time vocalizing and than proceeded to build a nest together and lay eggs on opposite sides of the same nest.
The natural conditions of the composting nest supports safety, heat, moisture, pH, and microbial environment needed to stop fertile eggs from being destroyed by fungus,
weaken the shell to help young tortoises emerge, share parent’s gut flora, and provide temperatures to produce a mix of male and female offspring.
Given the benefits, some stewards allow captive nests to hatch naturally but most keepers collect the eggs use incubators.
Similar to other tortoises, the sex of hatchlings is determined by the level of estrogen during the second trimester of incubation. The largest factor is temperature. Based on a 2018 publication in Scientic Reports, another factor is seasonally elevated estrogen in the mother. More research is needed. At this point in time, most stewards incubate ~78 F° for mostly male; ~82 F° for a mix of males and females with highest healthy hatch rate, and ~85 F° for mostly females. At 90 F°, deformities of shell, face, and limbs have been reported. Lowering the temperature during the third incubation trimester to 79 F° may increase the healthy hatch rate. Keepers of other types of tortoises have reported higher hatch rates from fluxuating daily temperature to mymic nature.
The eggs start to hatch around 65 days after they are laid and may take up to ten days to fully emerge.
Often hatch during the wet monsoon season when there is plenty of food
Use egg tooth on nose to break through egg shell
Slowly turn around inside the egg as they slice open the egg
Once an egg is piped or broken, can take hours to days to emerge
They pipe egg to get access to more oxygen and stay in egg until they consume energy stored in their egg sac
If their egg sac is puntured they usually die. If a hatchling emerges with large egg sac, keep them on a wet steril
material without pressure on sac until absorbed. The egg sac is their food source until absorbed.
Under good conditions, captive raised Manouria emys can grow ~1-2 inches each year until they reach sexual maturity
Understanding there is a lot of variation, below are straight carapace lengths you're likely to see while raising a female Manouria emys phayrei.
Hatchling: 2.5in (6cm)
1 Year Old: 4in (10cm)
2 Year Old: 5.5in (14cm)
5 Year Old: 10in (25cm)
10 Year Old: 18in (46cm)
15 Year Old: 22in (56cm)
Through the efforts of a small number of dedicated stewards, captive born Mountain Tortoises / Manouria emys are regularly available in the US.
To promote the preservation of this species, we discretly connect interested parties as a Mountain Tortoise Matchmaker.
If you're interested in finding, rehoming, boarding, surplusing, or pairing Manouria emys, please send us an email to find your Manouria Match.