On the other hand, Roempp (2003, pers. comm.) states there are problems resulting from keeping Carettochelys insculpta together with other species. "I had problems with a large Macrochelodina rugosa female. The female got severely bitten several times into her back limbs by my female Carettochelys insculpta. Same happened to a large Macrochelodina expansa. Even being about the same size, the female Carettochelys insculpta repetitively bit the back limbs of the both Macrochelodina specimens. On the other hand, the male Carettochelys was never aggressive towards other species. I have no idea if the aggressive behaviour depends on the gender of the aggressor." (Roempp, 2003, pers. comm.) The senior author kept all four of the examined specimens with juveniles and adults of Emydura subglobosa subglobosa, a sympatric species, and no aggressive behavior has been observed towards this species whatsoever.

Water

     As for the water temperature, there are a number of different views. Dorrian (1994) suggests that the water is heated to a constant 26-27°C while Bargeron (1997) claims the water temperature must be between 26.1°C and 30°C. Georges and Rose (1993) recommend water temperature of 28-30°C. This range (28-30°C) has been found as being optimal for the species by the authors themselves. Temperatures above 32°C and below 26°C are not recommended as the body temperature of the species depends purely on the temperature of the water that surrounds it. In the wild, a specimen can regulate its body temperature by either swimming deeper or under roots and logs and thus entering colder waters or staying just beneath the water surface or swimming towards the shore and thus entering shallow and warmer waters. This natural thermo regulation is absent in indoor captivity due to a constant temperature within the entire enclosure. On one occasion, a Carettochelys insculpta specimen was observed in water of 22°C. It rested at the bottom of the tank, being motionless for the whole period of two hours, except for the times when it swam towards the surface in order to get some air. Once the water temperature was raised to 28°C, other constraints staying unchanged, the specimen became active.

     Carettochelys insculpta is a hard water specialist turtle much like the fish of the African Lakes such as Lake Malawi. The natural conditions from which it comes from is largely rivers that have a limestone base. This means that they are high in carbonates and hence have a high but very stable pH of around 8.0 to 8.3. The KH and GH of the water is around the 18 to 25 dH. Another factor to take into account is that Carettochelys insculpta is a scuteless turtle, like soft shells (e.g. Apalone spinifera) and hence does suffer from a predilection to fungal and bacterial infections that at their worst can lead to SCUD (Systemic Cutaneous Ulcerative Disease). In particular the fungal agents include a group of organisms that thrive in neutral water (6.5 - 7.5) and are largely killed off at the higher pH. Therefore the high pH regime improves the skin condition of the turtle. A specimen with irritation of the skin on the carapace will rub its own skin off. Freshwater turtles react osmotically with the surrounding water and when the water has a high level of dissolved salts this also reduces the workload of the renal system.

     One of the ways that we learn how to look after species is to look to their natural environments and work out what they need based on what seems to restrict their distribution in the wild. Interestingly this species only occurs in limestone-based rivers. It only occurs in rivers of high pH, high conductivity and high alkalinity. This means very stable, very clear water. In fact, when working on the Daly River with this species, there is up to five meters of visibility. Therefore when making enclosures for this species, and in particular the large numbers we were dealing with due to the experiments we were running, it became apparent that we needed to duplicate this. See figure 2. for the recommended water chemistry parameters for this species.

     Carettochelys insculpta is omnivorous, but tending more toward herbivory than toward omnivory (Groombridge, 1982). In Australia, Carettochelys feeds on the leaves, fruits and flowers of riparian vegetation, especially the Fig Ficus racemosa, the bush apple Syzygium forte, and Pandanus aquaticus (Schodde et al., 1972; Georges and Kennett, 1989). Other foods include aquatic insect larvae, crustacea, mollusca, fishes and mammals possibly eaten as carrion, and aquatic plants such as algae, Vallisneria sp. and Najas tenuifolia (Cogger, 1970; Schodde et al., 1972; Georges and Kennett, 1989). The wide range of foods eaten provides great scope for opportunism, and the diet varies greatly with the foods available from locality to locality." (Georges A. and Rose M., 1993)

     The specimens examined by the senior author were fed by various items including dandelion leaves (Taraxacum officinale), apple fruit (Malus sp.), pear fruit (Pyrus sp.), banana fruit (Musa sp.), grapes (Vitis sp.), tomato (Lycopersicon sp.), lettuce (Lactuca sp.), chicken egg white, earth worms (Eisenia and Lumbricus sp.), chopped poultry white meat (Gallus sp.), and fish (Gadus, Melanogrammus, Alburnus sp.). The plant-animal diet ratio was 3:2. Providing rich diet is one of the keys how to maintain this species healthy. All specimens proved to be omnivorous, very vigorous eaters. Their feeding technique includes touching the food with their proboscis as if they were sniffing it, grabbing the item between their jaws and sucking it in. The claws on the front flippers may be used to tear bigger items into smaller pieces.

     Hatchlings and juveniles with a carapace length less than 100 mm were fed once a day. Juveniles with a carapace length greater than 100 mm and less than 150 mm were fed every second or third day. Semi-adult specimens with a carapace greater than 150 mm were fed twice a week. As the observed specimens were getting older and bigger, the amount of food given to them increased as well. No matter at what stage, each specimen received as much food as it was able to eat in approximately five minutes. Their feeding time was either in the morning or in the evening, when they were most active.

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