Why do we worry SO much about humidity......read question:

[Kelly G]

Why do we all worry so much about humidity when my hens routinely hatch chicks all summer long with 90% humidity?

I don't get it.

I'd like to do a staggered hatch....but I hesitate to do it because of all the talk about humidity

 

[Glenmar]

From what I am reading the only time humidity is really important is hatch time.
I would hesitate to hatch with others not ready due to bacterial contamination, but maybe they would not be affected.

 

[cmom]

My opinion in hatching with a broody, mom does get off the nest once in awhile so fresh air can circulate around the eggs. In an incubator it is a closed environment so the humidity is more critical. That is just my opinion.

 

[Kelly G]

Very interesting points...I do take the top off once a day, but that may not be the same...

 

[Saltysteele]

we are doing staggered hatches.

for the 3-4 days we turn the humidity up, we have found it doesn't really affect the other incubating eggs.

we have a redwood cabinet incubator, so what we do may not work for other styles. we do still pop it open once, about midpoint, during "lockdown" to quickly turn the eggs that aren't ready. as soon as the last chick has hatched, we drop the humidity back down. i've watched air cell progression and the 3 days has not affected it. the air cell is created by moisture moving from a 100% humid environment (inside the egg) to a less moisture-saturated zone (outside the egg). 3 days of humidity being 20% higher outside is not going to affect moisture moving out of the egg that adversely. it is still going to exit the egg. the moisture would still leave the egg if the outside humidity was 99%, as there is always a struggle for equilibrium.

out of the viable eggs during the last 3 hatches, we have had hatch rates of 85% (one died trying to get out, the other died a couple days before hatching; this was the first hatch, not really a staggered), 100% and 100%. incubating and hatching in the same unit, just placing trays that would hatch first under those that would hatch later. our 4th hatch is this weekend (we've done turkeys and chickens).

i know this will incite some people, but i don't accept "no you can't because this is what i have been told"

to be totally safe, though, i think you would do well to purchase the 2nd incubator (saw it in your sig)

 

[cmom]

I have a cabinet incubator I use for incubating and a styrofoam one for hatching.

 

[ChickieBooBoo]

For staggered hatches the extra humidity won't affect the other eggs, as long as its not for an extended period of time like a week or so