Are chickens warm-blooded? The short answer is yes. But the long answer means understanding how this impacts the behaviors and day-to-day care of your flock.
Are Chickens Warm-Blooded?
Caring for livestock begins with learning the basics about your chosen species, but after a time, it can be beneficial to dig a little deeper into the physiology of your animals. We often first learn how to care for our livestock, but later, it can be useful to gain a deeper understanding of the whys.
To best understand a particular living creature, compare them to others and see where there are similarities and differences. For instance, what attributes do chickens share with, say, mammals? At first glance, it might seem like chickens and mammals have little in common because there are major differences such as feathers instead of fur and eggs instead of live birth. In fact, you could almost make a case that chickens have more in common with reptiles.
But the last item on this list — that chickens are warm-blooded instead of cold-blooded — is extremely important and has a large impact on the care and behaviors of your chickens. Don’t be fooled by the eggs or scaly legs: Because chickens are warm-blooded, their metabolism and lifestyle has more in common with mammals than reptiles. Understanding this fact can help you understand the whys behind a lot of other aspects of your chickens’ health and life — from calorie needs and shelter requirements to activity levels and mothering instincts to intelligence. Examining the biology behind the whys can help make you a better chicken keeper and help you enjoy your flock even more.
Your Active Chickens
Warm-blooded animals must maintain a specific body temperature to survive. For chickens, this number is about 105 to 107°F. Even if the air temperature is far colder — even below freezing — a chicken’s body temperature will consistently remain within that specific range. Where does that heat come from? It comes from metabolizing food — that is, taking the energy contained in food and converting it into heat.
The bodies of cold-blooded organisms such as reptiles (also amphibians and fish) don’t perform the work of converting food to heat in the same way. Instead, the bodies of these animals tend to be roughly the same temperature as their surroundings. This is why you see snakes or turtles sunning themselves on a dark rock in the morning; they’re trying to warm up enough to function effectively, and their body temperatures can fluctuate wildly throughout the course of a day in some cases. But the warm-blooded nature of birds and mammals means they can be much more active all day long and must eat throughout the day to power this activity. (Cold-blooded animals can eat much less often because they aren’t powering an internal furnace.)
For chickens, foraging can take up more than 60% of their active hours, but the muscles of cold-blooded reptiles can’t perform for long periods of activity; the energy just isn’t there. Chickens, on the other hand, love to explore and actively poke and peck at the world all day long; again, their warm-blooded physiology makes them behave more like mammals despite the other biological differences between the two.
Parental Instincts
The warm-blooded nature of your chickens also plays a role in their parental behaviors. Think about reptiles or amphibians for a minute; most take an extremely hands-off approach to parenting. In many cases, reptile parents don’t linger after the nest has been created and the eggs laid, so the juveniles may hatch and start off life in the absence of a parent. (Alligators are an anomaly to this.)
On the other extreme, mammals are probably the most hands-on when it comes to caring for and raising their young. Chickens, being warm-blooded, have parental behaviors that are much closer to mammals. Besides the obvious “brooding” behavior of wanting to maintain a nest and incubate eggs, hens are also quite protective of their hatched chicks, constantly offering them a warm wing to hide under.
Hens serve as role models, showing their chicks how to forage effectively and demonstrating proper roosting techniques. The hen and her chicks form an emotional attachment, and the chicks learn to seek her guidance to differentiate threats from nonthreats. Hens teach their chicks to recognize her comforting clucking sounds as well as her warning calls. The term “mother hen” doesn’t exist for nothing!
And don’t forget the protective role a rooster plays as guardian of the flock. All these active parenting behaviors are possible because of the high energy levels that come with being warm-blooded.
Intelligence
By and large, warm-blooded animals — mammals and birds — are the most intelligent in the animal world. Their complex hearts and high metabolisms ensure that plenty of oxygen is available to power large brains. This means that you’ll find species such as raccoons and ravens on lists of the most intelligent animals, but you won’t find a single snake or salamander (though cold-blooded octopi are pretty clever). So appreciate the intelligence of your warm-blooded chickens; when compared to the vastness of the animal kingdom, chickens are actually quite smart!
Lori Marino, founder of the Kimmela Center for Animal Advocacy, published a review article called “Thinking chickens: a review of cognition, emotion, and behavior in the domestic chicken,” (Animal Cognition, 2017). It showed that chickens can perform basic logical inferences, perceive simple concepts about time and numbers, exhibit positive and negative emotions, possess individual personalities, and may even be self-aware. So while your hens obviously won’t perform complex tricks at the level of a dolphin or dog, they are very intelligent — as any long-time chicken keeper will readily attest.
Cold Weather Needs
When cold weather approaches, snakes, turtles and other reptiles have different cold-blooded behavioral techniques to respond to winter. Often this involves burrowing and brumation — the cold-blooded equitant of hibernation. But the chickens in your flock don’t hibernate, can’t migrate out of the weather and, being warm-blooded, must stay active and warm all winter long.
We instinctively understand that our chickens need shelter in cold temperatures, but we don’t necessarily think through why this is the case. Part of the reason has to do with the original natural habitat of chickens; they’re native to the warm jungles of Southeast Asia. This means that while modern chickens can handle a certain amount of cold weather, they’re a prone to frostbite on their legs and combs and aren’t nearly as comfortable when it’s cold. So providing a warm winter shelter helps mitigate these issues.
But there’s another good reason why we provide our chickens with a shelter from the cold, and this has to do with the fact that your flock is made of warm-blooded creatures. A chicken’s body is going to do whatever is necessary to maintain its needed 105- to 107-degree Fahrenheit core temperature. So if a chicken is exposed unnecessarily to prolonged cold weather, extra calories are needed to order to metabolize enough heat to keep the chicken alive. Extra calories mean extra feed requirements, so farming costs increase.
If a chicken’s body is working extra hard in the cold to maintain core temperature, the body may scale back on energy-demanding biological functions — such as egg laying. Providing a warm shelter means that the chickens are more comfortable and their bodies are more efficient because biological functions don’t need to expend as much energy just maintaining a constant body temperature.
Chickens also have several biological ways to keep their body temperatures under control on hot days; they can constrict or widen blood vessels to either keep heat in or help it disperse. They can increase blood flow to their combs and wattles to help dissipate heat and fluff up their feathers to permit extra airflow. Too much heat isn’t a good thing for warm-blooded animals either.
For chicken keepers, it’s important to study housing requirements, winter needs and how to keep humidity in the coop at a proper level. This will all help to keep your flock healthy.
Are Chickens Warm-Blooded? A Better Understanding
Studying the physiology of your chickens and their contrast to other animal classes may seem a bit superfluous, but it can really help you gain some insight into why your birds act the way they do. The naming and classification of animals has a long history and is certainly among humanity’s oldest scientific endeavors; taxonomy (in a way) is mentioned as far back as the Biblical Genesis.
The type of scientific exploration into your birds shown in this article can give your another “layer” of enjoyment with them. Chickens are amazing creatures and a deeper exploration into their interesting lives can be well worth the time and effort.
This article about are chickens warm-blooded was written for Chickens magazine. Click here to subscribe.
