My opinion (having rescued so many "odd" chickens and guineafowl these last 15 years) would be NOT to cull. The bird seems to be perfectly healthy and as long as it can roost, dust bathe, sun bathe, and enjoy life like any other chicken, there is no need to kill it just because another is picking on it. If you're going to cull roosters just for being truthful to their skittish/pecky/rowdy nature, then with all due respect, please refrain from owning roosters at all. Hens do very well without roosters, and sometime they lay even more relaxed without them. Next time, please consider giving the poor thing up for adoption. Unless you want some soup on your table of course! I always eat my super mean ones. RIP jackie 
