Reproduction of the pig-nosed turtle Carettochelys insculpta
(RAMSAY, 1886) at the
Rotterdam Zoo. Radiata 14(3):3-12.
Gerard Visser & Henk Zwartepoorte
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| Fig. 6. Immediately after hatching the egg membrane and a few blood vessels are still visible in this specimen. |
Hatching
Just a few minutes elapsed between the first hole in the egg shell and the complete hatching. One
hatchling needed five minutes to complete the process, but took a breath at the surface whilst hatching.
All embryos are situated in the upper part of the egg during incubation, and as soon as the egg sinks to
the bottom of the tank they turn upside down to the bottom, such that the heavy embryo is then at the
lowest point.
At hatching the carapace has visible ribs and is shaped just as round as the egg. The weaker parts,
including the spiny edges, spread out after 30 to 45 minutes and become tighter during the following days.
On a number of occasions the hatchlings are completely covered with the egg membrane attached to the
umbilical chord, which falls off after several minutes. On two occasions the keepers had to free the
hatchling from this membrane as it was also attached to the fore limbs and neck of the hatchling. On some
occasions the membrane and umbilical chord stayed attached to the plastron for two or three days.
| Egg No. | Incubation Temperature (°C) | Incubation Time (days) | Hatching Method | Hatch Date |
| 1 | 31 | 97 | submerged | 04/17/2005 |
| 2 | 31 | 97 | submerged | 04/17/2005 |
| 3 | 32 | 93 | submerged | 04/13/2005 |
| 4 | 32 | 89 | submerged | 04/08/2005 |
| 5 | 32 | 89 | submerged | 04/08/2005 |
| 6 | 32 | 89 | submerged | 04/08/2005 |
| 7 | 32 | 88 | submerged | 04/07/2005 |
| 8 | 32 | 88 | submerged | 04/07/2005 |
| 9 | 32 | 88 | submerged | 04/07/2005 |
| 10 | 32 | 88 | submerged | 04/07/2005 |
| 11 * | 30 | - | - | dead embryo |
| 12 * | 30 | - | - | dead embryo |
| 13 | 30 | - | - | infertile |
| 14 * | 30 | - | - | dead embryo |
| 15 | 28 | 109 | incubator | 04/28/2005 |
| 16 | 28 | 110 | submerged | 04/29/2005 |
| 17 | 28 | 110 | submerged | 04/29/2005 |
| 18 | 28 | still incubating | - | - |
| 19 x | 30 | 140 | opened | 04/29/2005 |
| 20 | 30 | still incubating | - | - |
| 21 | 30 | 116 | submerged | 05/05/2005 |
| 22 | 30 | 116 | submerged | 05/05/2005 |
* On May 5, this egg was opened after it did not show any pulse on the Buddy-
Egg. It contained a full grown, dead embryo.
x On May 29 this egg did not show any pulse on the Buddy-Egg. It was opened
and it contained an almost fully grown, living embryo. After removal of the egg- Data
membrane the "hatchling" was housed in a small plastic aquarium with shallow On the hatchwater.
Although looking very lively it died after two days.