Macrochelys temminckii

Pond / aquatic tank of very large volume (aquatic to semi-aquatic setup, possible low haul-out area)

Strictly SOLITARY husbandry (aggression, cannibalism). An adult in practice requires a custom-built pond of several thousand litres; the minimum dimensions indicated only suit a subadult. WARNING: a protected species (CITES Appendix III, IUCN 'Vulnerable') and potentially dangerous — its keeping is regulated, or even prohibited depending on the country/state (in France, a certificate of competence and an opening authorization may be required). Be sure to check local legislation.

An entirely aquatic species: the humidity parameter is of little relevance, as the animal lives submerged. Absolute priority to water quality and temperature.

Avoid gravel of intermediate size (risk of ingestion and intestinal impaction). A bare bottom or fine sand makes maintenance easier and limits waste accumulation.

Beneficial, especially for juveniles (vitamin D3 synthesis, shell health), but the species basks rarely: a low to moderate UVB (UV index ~2-3) above a possible haul-out area is sufficient. The priority remains a varied diet rich in calcium/vitamin D via whole prey.

The heart of husbandry: a large volume of fresh, clean and dechlorinated water, with powerful and oversized filtration (a very messy animal). Regular water changes and strict monitoring of ammonia and nitrites — skin burns and infections are common in fouled water. The water depth must allow the animal, resting on the bottom, to reach the surface without having to swim (often shallow for juveniles). Water temperature maintained between 20 and 26 °C.

Southeastern United States (Mississippi River basin): rivers, lakes, backwaters and freshwater swamps.

Carnivore / Piscivore — Whole fish, crayfish, crustaceans, earthworms, molluscs, carrion, occasionally small rodents or whole birds.

Varied, whole prey (with bones/shell for calcium). Avoid an exclusive diet of fish rich in thiaminase (goldfish, smelt), which causes a vitamin B1 deficiency. Feed juveniles more often (2-3x/week) and adults sparingly (1-2x/week) to prevent obesity and hepatic lipidosis.

Clutch 10–50 eggs/young. A single, annual terrestrial clutch. Incubation ~100-140 days with temperature-dependent sex determination (TSD). Late sexual maturity (~11-15 years, later in the wild), which makes the species vulnerable to overexploitation.

• Respiratory infections (water too cold or of poor quality)
• Shell rot / ulceration (SCUD, bacterial or fungal infections)
• Metabolic bone disease (calcium/vitamin D deficiency, Ca:P imbalance)
• Thiamine (vitamin B1) deficiency linked to an exclusive diet of fish rich in thiaminase
• Skin lesions and burns, abscesses linked to poor water quality (ammonia)