Yes, chickens have a sense of smell. Scientists are still researching this sense not only in order to understand how chickens use their sense of smell, but also in order to understand the behavior of other birds which are more difficult to study because they are not domesticated.
Scientists have found that chickens prefer smells they are familiar with throughout their life. This may be why chickens are picky about changes in the type of bedding used in their coop and sometimes refuse to eat when you change the type of feed.
Chickens may also use their sense of smell for social communication; this is a new field of research. We all know our backyard flocks have a complex social order. Could it be that a bossy hen that attacks another hen is reacting to a smell? We don’t know yet, but maybe if scientists learn more about this sense, we can spray the bird getting attacked with a special odor to get the other birds to stop pecking at it.
How good is a chicken’s sense of smell?
You may find articles claiming that chickens do not have a good sense of smell. This was generally thought to be true until recent genetic research found that chickens have many genes dedicated to interpreting odors. When genes are present, it is because an animal’s senses are picking up information from the environment. In fact, scientists discovered a whole new set of olfactory genes in birds that are not present in mammals, they do not yet understand the full function of these genes.
It is not clear exactly how well chickens smell because scientists do not fully understand the function of all the genes connected to this sense. However, it can be generally estimated that they probably smell just as well as humans. If their coop reeks of ammonia, your hens will appreciate the fresh smell of new bedding.
Can they smell predators?
Yes, there have been behaviour studies suggesting that hens can smell fear. This comes down to the fact that if the scent of a predator is placed near a chicken, they will react as if that predator was present.
What does this mean for your backyard birds? When chickens get the scent of a predator, they will be afraid and stressed. They will try to find a safe area to hide, such as under a bush, inside their coop, or in a tree with low branches. There will be some initial commotion, as the birds cry danger to warn the flock, and then quiet as they hide from the predator.
Can they smell food?
Many chicken owner’s have been heckled by hens refusing to eat the new brand of feed in their bowl. Maybe the store was just out of the usual brand, or maybe they switched to a new brand for better nutrition. Either way, they wonder if their hens are going to starve themselves as they turn their beaks up at the new food. Chickens can smell their food and they suspect unfamiliar odors.
Mixing in a bit of the new food with the old food will make the smell of the food more familiar to the hens and they will be more likely to indulge you by eating their new feed. Once they get used to the smell of the new feed, you can stop mixing in the old feed. Also, chickens find a lot of delicious bugs and are likely to go ahead and eat if they are hungry enough. So you don’t need to worry about self-inflicted chicken starvation.
What smell do chickens dislike?
Chickens generally do not seem to like the smell of citrus and will often refuse a slice of orange, but will attack a pear core with utter abandon. There are also herbs that chickens dislike.
However, all of these preferences may have to do with how familiar they are with the smell. This may explain why some chickens love a bit of orange for a treat even though most chickens avoid it. Chickens like smells that are familiar to them, so they may not chow down on lavender, if they are not used to it. But if they are raised with a lavender plant nearby, it is not likely that the odor will offend them.
Chickens have memories connected to odors. This is good news for you, because once their new bedding or new feed is a familiar odor they will no longer have an aversion to it.
Some herbs that chickens may not like are lavender, chives, marigold, catnip, and spearmint. But even though there are claims that chickens do not like these smells, there are also stories of hens choosing to nest among these very herbs. So if you are trying to keep chickens out of an area I would not depend on any herbs that they are already familiar with, and even if a new scent keeps them out of the area, they are likely to get used to it over time and will enter the area, especially if any bugs or loose dirt are present. The only sure way to keep chickens out of an area is fencing.
Chickens use their sense of smell for finding food and avoiding predators. They prefer scents that are familiar to them, and they form strong memories associated with odors.
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