Have you ever wondered whether or not your chickens recognize each other? Or recognize you? Could, say, pick you out of a lineup? Or wondered if - treats notwithstanding - they are actually happy to see you when you come home from work? Well it turns out that not only do your chickens recognize YOU, they can also recognize up to 100 other flock members - as well as the family dog.
Interestingly, chickens have similar eyesight to humans (actually theirs is even a little bit better!) and can recognize up to 100 different flock members by sight. It's thought that chickens recognize the shape of the head and comb of their flockmates - and will accept them even if they are different breeds. (Although I'm not sure what parameters they use to pick out their 'humans', since my hairstyle changes pretty often and sometimes I'm even wearing a hat!)
I know from personal experience that chickens can also recognize other types of animals as being friend or foe - and even a specific, individual animal as a friend or foe. For example, if our dog comes bounding around the corner past the run, our chickens don't even react. However, on the few occasions that a neighbor or friend's dog has been visiting, the chickens immediately freeze and sound alarm call. And speaking of which, chickens are capable of making at least 30 different sounds, each of which has a specific meaning which they all recognize.
It's interesting to note that newly hatched chicks recognize their mother by sight and sound. Studies have shown that "when a sitting hen was removed in the dark from her chicks and another broody hen put in her place, the chicks still found their mother hen without being able to see her. When the hen was disguised by various means, her chicks came to her anyway." [source]
What's fascinating though, is that it doesn't seem to work the other way - in that a broody hen will generally accept any chicks and seems to respond to the sounds they make (i.e, a distress call if they're cold or lost) instead of their appearance. Apparently her maternal instinct kicks in and she feels responsible for ALL the baby chicks! This trait makes it very easy to slip day-old chicks that you have hatched in an incubator or even bought at the feed store under a broody hen. She will most likely take to them as if they were her own. And the baby chicks will respond to her warmth, since their primal instinct drives them to a heat source.
One thing that's for sure is that chickens don't recognize each other by any sense of smell. Chickens actually don't have a very developed sense of smell at all since it would have very little utility for them in the wild. So if you are adding new flock members to your flock and trying to trick your chickens into not being able to identify them, rubbing everyone with dryer sheets (don't ask..that's actually advice I've read online!) or spraying them with white vinegar to 'mask' their scent isn't going to work.
And don't put the new members on the roost after dark when you lock up the coop...when the sun comes up, your chickens WILL able to pick out the newcomers out of the lineup!
Now that we know that chickens do recognize each other by sight, and we know that they can differentiate between flock members, it's interesting to watch them interact. Mine, interestingly enough, don't necessarily seem to prefer hanging around with those who look the same as they do, i.e. are the same color or breed. They do seem to choose a buddy during free range time however, which will generally stay consistent. Do you find that your chickens each have a BFF (best feathered friend)?