Aquatic turtles

Housing

• In an outdoor pond, made of concrete, PVC liner (at least 0.8 cm).
• During the earthworks, the ground is levelled so as to create ledges at different heights.
• Once the pond is built, you must wait at least 2 or even 3 months before releasing the turtles into it. The gradient and the slopes should be designed so that the turtles can climb out at any time, onto the edge of the pond for a spot of sunbathing.
• Examples of plants for ponds: lotus, water lily, water hyacinth, buttercup, papyrus, horsetail, iris, water plantain...
• Tropical species that, because of their thermal requirements, cannot stay outdoors all year round need an aquarium.
• The aquarium is an artificial environment in which it is particularly unrealistic to recreate a natural biotope, so priority will be given to impeccable hygiene.
• The layout includes a land area that takes up one third of the total surface of the aquarium.
• The tank is cleaned about once a month, and the filter 2-3 times a month.

Diet:

Aquatic turtles are not all carnivorous, as many of us are inclined to imagine. A few species, or the juveniles, are carnivorous, and on reaching adulthood they become mainly herbivorous. But the vast majority of aquatic turtles are omnivorous.

In captivity, the choice of food offered to turtles must take account of the dietary specificities of each species. Adults are fed at least 2 or 3 times a week, whereas the young must feed daily. They should be offered as varied a diet as possible.

Foods suited to turtles' needs:

• Plants and fruit: algae, watercress, water hyacinth, spirogyra, dandelion, cos lettuce, beetroot leaves, broccoli leaves, turnip leaves, endives, chard, spinach, hibiscus leaves and flowers, mulberry leaves.
• Meats: calf's liver, poultry heart and gizzard.
• Vertebrates: mice, rats and other rodents, frogs, chicks, whole fresh fish (minnows, roach, mosquitofish, guppies, eels, sand eels) but also pieces of salmon and hake fillet, frogs' legs.
• Invertebrates: aquatic and terrestrial snails, crustaceans (crayfish, shrimp…), bloodworms and earthworms.
• Artificial foods: reptile foods (dehydrated pellets), pudding (a coloured gelatinous paste whose ingredients vary according to inspiration! For example: cooking gelatine, fresh trout, fresh shrimp, mussels, beef escalope, eggs, milk, baby-food jars, rabbit or poultry liver…)
• Vitamin supplements: if the diet is balanced, there is no need to add any. On the other hand, fragments of oyster and egg shells can be scattered on the bottom of the pond, which the turtles eat regularly for the calcium they provide. Cuttlebones are also recommended.

Unsuitable foods:

Plants:

• Lettuce, escarole, courgette, carrot, cucumber, mushrooms, strawberry, banana, apple, Brussels sprouts, cauliflower, Chinese cabbage, and turnip
• Meats:
• Brains, kidneys, minced steak, cooked or raw ham.
• Fish:
• Sardine, smelt, anchovy, shad, carp, herring, bullhead, catfish, goldfish
• Dried shrimp or gammarus.
• Dog and cat foods are strongly discouraged!

Reproduction:

In general, females are larger than males, but the best criterion for telling them apart is the thickness of the base of the tail, which is greater in the male.

Tropical species mate throughout the year, but the females tend to lay each year during the same periods. The mating displays are more or less complex depending on the species, and more or less markedly violent. Because of his aggressiveness, the male can kill the female, in particular if she is not willing, so it is advisable to separate them and to put them together in the same tank only once or twice a year to bring about mating.

Laying: it takes place 3 to 4 weeks after mating. The female looks for a spot that is sunny, damp and located fairly close to the pond, and often near the fence of the enclosure. She digs a nest and lays her eggs in it before filling it back in. The entrance to this nest can be detected by a trained eye, but may quite easily go unnoticed, so meticulous is Madam Turtle!

Females never look after the eggs or the newborns, with rare exceptions. The eggs should be collected as soon as possible; the longer you wait, the riskier the operation. Turning over a turtle egg can cause the death of the embryo. They must then be placed in an incubator.

Hibernation:

Aquatic turtles from temperate climates hibernate in the outdoor pond, and most hibernate in the water, but some species opt for the land part of the pond. A wooden or solid shelter is then needed, as well as several large piles of plant matter (used straw, mown grass, dry leaves or manure) placed in the enclosure, under which the turtles can take refuge.

Common diseases

In aquatic turtles, most illnesses are linked to the quality of the water, the absence of a heated dry area, or an unbalanced diet.

The key point: clean water, a heated dry area where the turtle can dry off completely, and a varied diet prevent most problems.

Swollen, closed eyes are very common and suggest a lack of vitamin A. The turtle then struggles to open its eyes and eats less.

Soft, discoloured or damaged patches on the shell signal a shell condition (“shell rot”), often linked to dirty water or the inability to dry off properly.

Unbalanced swimming (the turtle tilting to one side), laboured or open-mouthed breathing, suggest a respiratory tract infection. It often occurs when the water or the air is too cold.