Indochinese Tortoises (Manouria)

Screen Shot 2014-04-22 at 5.01.21 PM

 

 

 

Manuoria emys emys, courtesy of Kelly Hull

General

Manouria tortoises are some of the most primitive tortoises and are most similar to the earliest species in the fossil record. In general, they are found in Southeast Asian in the mountain regions, usually near water. They prefer cooler temps than most tortoises. Because of large protrusive scales on the thighs, they are sometimes called ‘six-legged tortoises. They do not brumate, and there is no record of aestivation- although it is often noted that hot weather is very dangerous for them.

The species and sub-species include:

  • Manouria emys, Burmese Mountain, or Asian Giant Tortoise (Schlegel & Miller, 1840)
    • M. e. emys, Burmese Brown Tortoise (Schlegel & Miller, 1840)
    • M. e. phayrei. Burmese Black Tortoise (Blyth, 1853)
  • M. impressa, Impressed Tortoise (Gunther, 1882)

Burmese mountain tortoise (Manouria emys)
Often called the ‘Asian giant tortoise due to the size- it is the second largest mainland species. It has two subspecies- M. e. emys, the Burmese brown tortoise, and the slightly larger M. e. phayrei, the Burmese black tortoise. The easiest way to distinguish the two is supposed to be looking at the plastron. The pectoral scutes meet in M. e. phayrei but not in M. e. emys. They seem equally at home in nearly semi-aquatic situations as in stony savannas. They are both worshiped and eaten in their native range. They are considered critically endangered due to hunting for food and pet trade, and habitat destruction.

Impressed tortoise (Manouria impressa)
About half the size of the Burmese mountain tortoise but would be distinctive because of the concave scutes and more angular appearance. Less is known about this less commonly kept species that seems to live a much more unobtrusive lifestyle than M. emys.

Description

Burmese mountain tortoise
Grows to 24 inches or 60cm long. Mostly dark, smooth carapace with subtle patterning, and thick scutes showing deep growth rings. Fairly low shell with some flaring and serration at the front and back. Plastron is the same color as the carapace. heavy scales on limbs. An especially large scale on the thigh gives the genus the name ‘six-legged tortoise’. The M. e. phayrei sub-speces is generally larger and darker than M. e. emys.

Impressed tortoise
Grows to 12 inches or 30cm. Variable carapace can range from yellowish/mustard to dark with red and orange tones. Scutes are lighter in the center and have a subtle pattern. Scutes are flattish with many being slightly concave- hence the name. Marginals are heavily serrated and flared in the front and back. Plastron is beige to brown, the head is yellowish or reddish.Heavy scales on limbs, as well as the over-sized scale on the thigh.

Screen Shot 2014-04-22 at 5.01.41 PM

 

 

 

 

 

(Len Brown. Young M.e. emys, M. e. phayrei, and M. impressa)

 

Range and habitat

Burmese mountain tortoise
Southeast Asia- Burma, southwest Thailand, Malaysia, Sumatra, and Borneo. Primary habitats are cool humid well-drained evergreen forests up to about 3,300 feet- wet enough that some authors consider them semi-aquatic even though they are often found in dryer, rocky areas as well. Often found hiding in leaf litter and less often in burrows.

Impressed tortoise
Similar to the Burmese mountain, with a more limited range. Myanmar, Thailand, Malaysia, and Vietnam. Often found between 3,300 and 6,600 feet of elevation and observed in bamboo forests. More partial to hiding in leaf litter than M. emys.

Reproduction

Manouria do not seem to have strict mating seasons, but like many species, the wet or rainy season triggers lots of activities. There is a short, non-aggressive courtship involving head nodding, Males may hiss or roar during courtship or mating, and the couple often seems to talk to each other with various noises. It has been noticed that each individual seems to have a distinctive vocal pattern.Unusual for a tortoise, this genus seems to form at least a partial pair bond, possibly for life.

Nesting occurs in April or May, and September and October. The female builds a large nest of leaf debris and detritus in a dry, sunny location that may take days to construct. She will lay about 40 (in one recorded case- 51 eggs, the largest clutch recorded for any land turtle) largish 60mm or so eggs. Also unique amongst tortoises- the parents and especially the female will guard the nest aggressively for several days and remains nearby for weeks! They have been observed chasing monitor lizards and humans. The female may also patch or improve the debris pile over time. The incubation may be as short as 70 days.

Captive incubation should be done at 85F (28-29c) with high humidity. Hatching generally takes 55-70 days.

For more information, see the articles on nesting and incubation and neonatal care.

Screen Shot 2014-04-22 at 5.01.47 PM

(Captive M. e. emys guarding the nest. Courtesy Len Brown)

 

 

 

 

Indoor housing

Aim for as much space as possible. 20 gallon tanks or tubs are the minimum for very young tortoises. 40 gallon tubs or tanks are OK for up to about 6″ long. 8′x4′ is suggested minimum for adults. Habitat should be
waterproof and secure. Hides and shelters are necessary- piles of leaf litter work well.. Live, ‘baby safe’ plants are helpful but may be eaten or knocked over. Some simple substrates are cypress or other hardwood mulch, or ‘Orchid Bark’ (high-grade Douglas fir bark). Many books or websites have good examples.

Outdoor housing

Outdoor pens should be spacious, secure from escapes and predators (or theft), and well-planted with things they can eat and foods and plants they can hide under. Fresh water and hides (leaf and debris piles if possible) are also needed. If nights are below 65-70F, there should be a heated shelter. If the days are hot and/or dry, there MUST be a misting or sprinkler system available.

This is an unexpectedly agile species that climbs well. Keepers often report finding them up in the foliage of shrubs, etc. Outdoor pens should be covered or designed to avoid easily climbed materials like chain link fencing. Corners should have covers over them so tortoises cannot ‘shimmy’ up them.

Environment

Warm but not hot, very humid and shady climate.

  • 68-79F (20-26c) preferred range. Can tolerate 60F (16c) or even lower short term and does not do well over about 86F (30c).- although other keepers report no problems in heat as long as there is adequate shade and misting.
  • Needs high humidity (80-100%), and rain spurs appetite and activities.
  • Gentle lighting with low-levels of UVB lighting are recommended. (Tortoises with regular access to unfiltered sunlight do not need UVB lighting.)

 

Water

A wide, shallow, easy-to-clean bowl of fresh water should always be provided. The bowl rim should be level with the substrate. M. emys especially enjoys being in water.

Diet

Mostly greens and plant matter, some vegetables and fruits, small amounts of protein. Prepared tortoise chows may be used instead or along with fresh foods.

  • Plant materials can be most lettuces, greens, flowers, mushrooms, hays, grasses, leaves or flowers of edible plants such as hibiscus, and leaves of fruit trees such as mulberry. Avoid using only a few items over and over, especially things like spinach, cabbage, and Iceberg lettuces.
    • Typical house or garden plants they enjoy would include Colocasia, Alacosia, Malanga, Philodendron, Pothos, Jack-in the-Pulpit
  • Vegetables and fruits can include shredded carrot, squash, pumpkin, bell pepper, apples, kiwifruit, etc. Some very good options are figs and papaya. Keep bananas, grapes, and citrus to a minimum. This should only be about 20% of the diet or so.
  • Meats should be about 10% or less of the diet. Live bugs and worms, snails and slugs, lightly cooked eggs, chicken, ‘oily fish’ (salmon, mackerel, etc.), dog or cat food and so on.
  • Some sources say that the impressed tortoise eats mostly mushrooms in the wild, and both species seem to enjoy them, the small ‘button’ mushrooms are not as good of a choice as things like oyster mushrooms, etc. would be. Understand that wild mushrooms are a source of vitamin D, which may be why these shade-loving torts like them, but farmed mushrooms may not have as much of the important nutrient.

Feed daily. Remove food when it goes bad. One way to help prevent overfeeding is to limit the higher calorie foods (such as fruits and meats) to an amount smaller than the tortoise’s head.

Other

  • M. emys is a large species with slightly specialized needs, and only keepers who can accommodate this should try to keep them.
  • Wild-caught Manouria are almost certainly heavily parasitized and generally badly stressed. They should be seen by a vet quickly for a full work-up and treatment. Because of this and their critically endangered status, we should only buy captive-bred animals.
  • Even though a fairly shy species, keepers often comment about their personalities and that they seem to form some attachment to their keepers.

Resources