There are 9 Bird BK aircraft on the U.S. registry that TailWiki has a page for. Every one is built from the public FAA record — year, serial, engine, home base, and registration history — and owners and pilots add photos, trips, and stories on top. The ones listed here were built between 1929 and 1930.
N10619
1930 Bird BK
Westhampton, NY
N731Y
1930 Bird BK
Baldwin Park, CA
N737Y
1930 Bird BK
Huntsville, AL
N767Y
1930 Bird BK
Williston Park, NY
N116M
1929 Bird BK
Canby, OR
N9184
1929 Bird BK
Rockton, IL
N9739
1929 Bird BK
Skaneateles, NY
N46K
Bird BK
Elbert, CO
N894W
Bird BK
Poplar Grove, IL