"http://wiki.answers.com/Q/How_long_does_rholde_island_hens_stay_pregant"
Grammatical issues, aside, I presume you meant RHODE Island red hens (there's no such thing as LONG Island red hens), which live about five years, the same as any other domesticated chicken.
Mine started mating yesterday and I found three eggs today. I have two Golden Comet hens, two Rhode Island Red hens and one Rhode Island Red Rooster.
10-12 years
As long as no humans collect them or critters eat them, they are very safe if the hens can set on them as needed to hatch.
As soon as the male serves the hens then the eggs should be fertilised.
I believe it is best if you dont introduce just one hen. there is a better chance of introducing two hens that know each other to another two hens which know each other. that way the hens you had alredy will not pick on the new hen. And i am not sure how long i would wait but it may take at least a few weeks. I had the same problem not too long ago!what you should do is put the third hen in a small cage inside the hutch/cage that you have the other hens in. only leave the third hen in there for a week at most! make sure that the other hens can see her! this will help in that the other two hens will get used to seeing her with them and then after the week release the 3rd hen with the othe hens ! they should get a long! good luck
42 weeks
Roughly 21 days.
Up to 12 years. But rarely in captivity
It takes about 24 hours for a hens to make an egg and after she has started to lay them them regularly she with lay 1 egg a day.
Most egg producers will cull the flock when they reach about 18 months old.
I want to know how long can be pregnant?