Humidity when incubating Marans eggs, increase, decrease, or same?

Kathy, if I'm incubating them with NO other breeds, I do up the humidity just a hair.  You'll get varying opinions.

I have hatched several batches of marans this year and have always raised the hummidity 5-8% depending on the climate during that particular hatch. I believe that hummidity greatly depends on your local, season, and also the Quality of the egg shell ie porious or non.  I believe more the real factors are, freshness of the egg, good fertility, and good stable temps and hummidity.  I have had untill reciently had a 85% hatch rate for the last 7 hatches, however on the last three whiched were shipped eggs I have had from 0% to 25% which is unexceptable for me.  I have focused mainly on marans this year and have had good sucess overall.

I've always incubated along side my other eggs with good results.

Today is my first attempt at hatching BCM's well so far (day 21) I have one baby. Took alittle over 12 hrs from pip to hatch. the humidity OH mymy! can you say I s**k . I had a digital that got stuck on 45% and dummy me kept adding water DAH dont do that. Well condenstion everywhere got new digital in there and can you say omgosh humidity went up to 90% quickly opened vents door till it stablized. I want it between 65 and 70 during hatch. It work on test hatch. But do you think it should higher or lower for marans.

We hatched several hundred Black Coppers, Wheatens and Gold Cuckoos over the past 2 years in a GQF Sportsman.  I have tried high humidity, low humidity and everything in between.  We now don't add any water until the day before the hatch.  We run all vents wide open for the entire hatch.  I really think this helps and we rarely get a bad chick.  We usually get around 80% live hatch with the Marans.  This works best for us, but it may depend on your local humidity, etc.

A chicken egg is a chicken egg, everything is the same.  If I have one of my other chickens go broody and place a few BCM eggs under her, do you think she knows the difffeance?  Does she add humidity or increase the temp some how?  Heck no, she just sits there until the eggs hatch.

Well, I have also heard both. I just finished a hatch with 8 BCMs, assorted eggs from my own hens, and 8 blue/blue splash marans.

I had humidity at about 30-45% through day 18, then upped it to around 65%. Had some problems with temperature at hatch on day 20 which may have been part of the problem. But my results were:

ALL 8 blue/splash marans hatched (one deformed and culled).
4/6 Welsummers hatched
3/4 black star/EE crosses hatched (one deformed and culled).
1/4 EE hatched

and 0/8 (NOT ONE) Black Copper Marans hatched. Candled them again after day 22 (now that I know better what to look for) and at least 4 or 5 had dark mass indicating a chick.

The woman I bought them from says she incubates with low humidity because the shells and membranes are thicker.

YMMV

I plan to try again in a few months. I would love to hear what others do and success rates.

Thanks for sharing that peeppeeppeep. I was thinking the same thing