This is an old thread but here goes anyway: All the Westphalians, Assendelfters, Braekels, East Frisian Gull, Friesians, Campine, etc are referred to as Gull types because of their resemblance to sea gulls. Wouldn't surprise me if Hamburgs and Buttercups were crossbred and related to the Gull types somewhere in their history too.
First breed of chicken that I've ever seen that looked like sea gulls...
I was just wondering if anybody knows of a breeder that works with these chickens. Apparently they were once fairly common in northern Germany but I've never heard of anyone in America raising them. I think they are absolutely beautiful birds and I have to admit they have one of the all-time greatest breed names. Here's a link to the Feathersite page on these:
Thanks so much for any information you guys have!