I only just inherited my flock. I've been told that the oldest that they have had here are about 5 years of age but I think many of them have been rescued battery girls.
My wee ones are only 19 and 21weeks. I'd love them to make it as long as I have had my oldest cat! (he's just turned 14)
I have a banty naked neck that is pushing 8 right now. She has managed to avoid every predator attack we have suffered. It help that she is as fast as lightening.
I had a Rhode Island Red hen. Bought her in Virginia Beach, VA.with a straight-run of six peeps. We moved to Ohio, bringing her with us. She adapted well. Laying an egg daily - even while we were on the road! an Easter Sunday was her last egg laying. She passed during her afternoon sun nap The following day.
I have serious doubts that 4% of the chickens made it to 16 years plus! My oldest was a 9yr old BR hen which laid eggs well up through 7 years and a sporadic egg here and there through the rest of her life. I don't doubt that chickens get older but, 16 is a real stretch! In my experience, most chickens will lay well for 3-4 years and go downhill quickly from there. There are few exceptions from what I have seen. Neat poll though! My oldest chickens currently are just over a year now and laying very well!
My Key West rooster Smokey is 10 this summer. I caught him with his momma and siblings while on vacay down there 10 years ago. His fertility is starting to drop, but he is still the best rooster ever!
we have two buff orp hens left from the first 4 birds we got(the BR rooster was mean, therefore tasty, and third orp hen got killed by a stray dog last fall)... they just turned two last month...
I still have one out of original 6 that we got as chicks 9 years ago, she is a California white. The last time she lay an egg was 5 years ago due to some illness she had, I think. The other hen I got from the same batch died when she was 7, after laying a egg a few days before she died.