There are several reasons why pigeons puff up their chests.
The most common reason a pigeon may puff up their chest is to impress their mate however they may also puff up their chest to help them preen, to scare off a predator or even as a sign that they are ill.
1. Mating
A desire to mate is the most common reason that male pigeons puff up their chests.
It is a major feature of the mating ritual of pigeons.
He wants to impress the female with how macho he is.
Puffing up his chest, along with other kinds of extravagant behavior, is what a male pigeon will do to attract a female’s attention.
2. Preening
Preening is an important part of a pigeon’s grooming rituals.
When pigeons preen they are cleaning themselves of dirt, dust, and debris that they have picked up or they are removing parasites.
They try to clean every feather in their plumage and obviously, puffing up their chest feathers certainly helps the grooming process.
Pigeons have what is called a uropygial gland that is just under their tails.
This gland excretes a waxy kind of oil, which they smear on their feathers.
This oil helps with insulation against the cold and as waterproofing.
As they try to reach every feather, ruffling their plumage makes it easier.
Another important part of the preening process is the proper alignment of their feathers, which helps them in flight.
3. Survival
Puffing up their chest feathers may also be a reflex action when they sense or face danger.
Many species in the animal kingdom resort to displays of bravado when facing a predator.
This is an attempt to appear bigger than they are and so frighten off the attacker.
Pigeons are pretty smart birds that are usually aware of what is happening around them.
Their first reaction to danger is flight, but even a wily pigeon can be caught unawares sometimes.
Imagine that one is cornered, facing a swooping falcon with talons extended or a creeping cat that is ready to pounce.
Instinct would cause them to puff up their chest feathers in the vain hope of stopping their stalker.
4. Illness
It has been suggested by some birdwatchers that puffing up their chests can be a sign of illness in a pigeon.
Pigeons can’t talk or do much except fly or walk on the ground to indicate their distress at being sick.
This behavior could be a symptom of not feeling healthy due to some sickness.
Of course, chest puffing in itself, isn’t an indication of bad health.
That kind of behavior would have to be taken in conjunction with other physical signs or behavior.
In Conclusion
Above are the different reasons pigeons will puff up their chests.
Bird fanciers and those that keep pigeon lofts will probably know their birds very well and can interpret their bird’s behavior and the circumstances, but when seeing this in feral pigeons, it is difficult to tell the reasons behind it.