It's the same for dogs. Dark-colored animals apparently inspire the wrong feelings in rescue/shelter situations -- possibly has something to do with lighting, or just basic human instincts that dark animals = scary. 

When I was getting my second dog, I went to the shelter specifically intending to get a black dog, sorta because of those statistics. Wound up with [url=http://i96.photobucket.com/albums/l162/murderdeathkilla/NM55.20994504-1-x_zpshblpiqgy.jpg]this fella[/url] instead -- just kinda happened.