@Philadelphia: These particular cuckoos came from Chickielady here on byc. She has had a line of feather shanked silver based Cuckoo Marans for 10 + years. She is honest and nice to deal with and said some of her males
can get some gold leakage but I am not seeing it on any of mine or on the hens as of
yet. I will be on the lookout, however, and cull out any that do. I have a black male I can use if I need to and might do some testing on my cuckoo hens with the black male and/or a blue male over the cuckoo hens but that is a longer process lol. I am just hoping at least one of my cuckoo males do not throw any gold leakage.
The silver birchens can sometimes come from matings of silver cuckoo x BCM or Blue coppers.
This site has a good explanation of where the silver and birchen come from (scroll way down the page)
http://frenchmaransclubaustralia.yolasite.com/notes-on-breeding.php
@ Hensandroos..Thank you. How are your cuckoos doing?