DEEP NEST AND LAYBIN MYTH ERADICATED
When the chameleon females of the oviparous species come to the end of the gravidity, they need to dig a tunnel in soil to lay their eggs.
Many keepers and even sites and groups recommend a very deep (10-12in) and spacy lay-bin filled with loose and soft substrate (dirt, dirt/sand mixture, coconut soil) to allow the females to dig easily.
However, it is not necessary and even not adviseable for the following reasons:
1. No female of any species digs so deep in the wild, so, it is unnatural. They dig surprizingly shallow nests: Panthers only about 3in (7cm), calyptratus 5in (12-15)cm. They dig till they get to roots or firm layer. Then they stop, lay the eggs, cover them with the excavated material and leave forever. (The exceptions and deep diggers are the females of extremely big species like Calumma parsonii or species from the Thorn-Bush from South and East of Madagascar like Furcifer verrucosus, labordi, antimena, that might, due to size of low laying level of moist soil, dig over one foot deep.)
2. The risk of collapsing the tunnel is the bigger, the deeper the substrate is. Females have been reported in captivity to have died in a collapsed tunnel and not only one life is then wasted, but many. And, for nothing.
3. Digging too deep exhausts the female unnecessarily and can cause discomfort, exhaustion, egg binding or even death.
So, what to do?
The best recommendation is to prepare a lay-bin with the following parameters:
SIZE: about 10 by 10 by 5-10in (25 by 25 by 12-25cm)(widths by height)
SUBSTRATE: sand
mixture of sand and soil
soil
coconut soil works in emergency but as it is acidic (pH 5,5 a 6,8) which is not good for egg incubation, and can cause impaction if incidentally swallowed by the female
never use perlite nor vermiculite, they can cause health problems for the female if ingested, inhaled and getting into eyes
STERILITY: bake or microwave prior to use
keep same temperature as ambient
for some species (e.g. F. lateralis) do not keep it too cold (might cause refusal to lay the eggs)
LAYER: keep it shallow, 4-5in (10-12cm) maximum
QUALITY: moist (not dry, not wet)
compacted (not soft, not loose)
PLACE: back corner of the cage
on the floor
in shade
DISTURBANCE: limit to minimum
better even cover the cage for privacy