Overwintering may be necessary for a number of reasons - often because a tortoise is sick or underweight and therefore cannot be hibernated. For successful overwintering a combination of environmental factors must be provided. There must be:
- Adequate light
- Adequate heat
- Humidity must be maintained within appropriate parameters
- Hygiene standards must be adequate
We do not recommend glass aquarium ('fish-tank') type accommodation for overwintering tortoises. These tanks are heavy, expensive and tend to be poorly ventilated. They are dangerous to handle and clean.
The following housing suggestions should give you some ideas for suitable accommodation. These basic outlines can be adapted as required.
1. For small tortoises
For very small tortoises (and juveniles) the plastic 'storage bin' containers sold in hardware stores are quite suitable. These are easy to clean and the large sizes provide reasonable space for individual animals or several hatchlings. For light & heat, a small clip-on type spotlight is usually adequate in these applications. A full spectrum tube can also be fixed to a wooden bar supported overhead.
2. For larger tortoises
The easiest solution is to make an indoor 'play-pen' type area. Plywood or covered chipboard planks can be obtained from hardware stores and fixed together to provide an area about 1m square. The necessary light fittings can be located overhead on a supporting rail.
Beware of over-drying tortoises accommodated indoors. Provide regular baths. To increase humidity (for tropical species) a cover can be fixed over the vivarium and a moist substrate employed. Non-tropical species, however, do require very good ventilation.
For providing a useful combination of light and heat, small spot-lights are recommended. These come in various sizes, from 20W-150W. For small units we find the 40W types usually suffice. Larger (pen-type) accommodation will require more powerful lights. These smaller sizes of spot-light can be obtained as useful clip-on fittings - these are highly flexible and can be moved as required.
In addition to some incandescent light, a genuine 'daylight' fluorescent tube is also recommended for long-term overwintering. Such tubes provide a close approximation of natural daylight and stimulate natural behavior patterns and good feeding. We recommend Reptisun 5.0 by Zoo Med Laboratories or Sun-glo (much cheaper, but still good). These tubes come in a range of sizes, from 18'' to 6'.
Lights should be switched off overnight to avoid stress and to provide a natural light cycle. In cold situations some additional heat will be required overnight - we suggest tubular heaters as used in greenhouses, or heat pads. A safe minimum overnight temperature would be around 15oC.
Be sure to provide a nutritious, well balanced diet over the winter period - try not to rely upon bland supermarket produce!. Even in winter some weeds and other 'wild-foods' can be found. The regular use of a multi-vitamin and mineral supplement is especially important over winter.