So I know I asked about the lid, holes or no holes but does everyone even use a lid during incubation? If the incubator is set at the right temp and humidity, does it matter?
GBtortoises said:I place lids loosely on each individual container for two reasons: 1-to be able to quickly see which container has which eggs in it. Each is marked on top with a letter that corresponds to information in a notebook that I keep. The information in the book contains which species the eggs are from, which group of that species and if known which female produced the eggs. Along with that date of nesting & number of eggs in the clutch as well as the final result of how many hatched and how many didn't. 2-as insurance in case one egg explodes, it doesn't contaminate the other eggs in the incubator.
Humidity is easiest controlled within the incubator, outside of each individual container by placing an open container of water in the incubator. I place a sponge in the water container to act as a wick in order for the moisture to be better drawn out of the container and into the incubator. The problem with trying to maintain the moisture within the individual containers is that it (the moisture) is constantly being drawn out of the containers and into the air within the incubator to humidify the whole thing. That is why some people experience problems with the incubation medium constantly drying out and requiring rehydration. Quite often when using vermiculite it gets dry on top but retains moisture under the eggs where there is no air flow. Then by being rehydrated it often times becomes too wet under the egg which can lead to the egg absorbing too much moisture through the bottom resulting in eggs cracking, exploding or hatching prematurely which is evident by very large yolk sacs. If using perlite or Hatchrite as a medium it remains dry to the touch but retains moisture within it's microscopic pores. The eggs never come in contact with moisture. The addition of a water container within the incubator provides the necessary humidity in the whole incubator, including each individual container, without the eggs having to be wet. This is much more in tune with what takes place in the nest cavity in the ground. The eggs sit, usually with some soil around them, in the bottom of the nest with an air pocket above where the humid air is. At no time do the eggs sit in damp soil unless extreme water penetration from heavy rains above ground flood the nest cavity. If that takes place it's very likely that those eggs will not hatch. This is one of the main reasons, along with adequate sun exposure for heat, that tortoises and turtles lay their eggs on embankments and on high ground, to avoid excessive moisture entering the nest cavity due to flooding or heavy rains. On side hills any water runs off faster. In captivity tortoises don't always have that option to lay on a south facing slope, so they make due.