Backyard Poultry Navigation
Humans have been keeping domestic poultry for over 10,000 years. While chickens were originally kept as production animals mainly for their eggs and meat, many more households are now keeping them as pets for showing, breeding, and companionship. When raised in the proper conditions and provided with the proper care, backyard chickens can easily live for 5 to 10 years with oldest bird on record reaching a remarkable age of 16 years. On this page, we will dive into the key developmental stages across their lifespans.
The life cycle for a chicken can be divided into 5 main phases:
Answering the classic question of “which came first: the chicken or the egg?”, we can confirm that a chicken starts its life as an egg. Most hens will lay a clutch of around 12 eggs over a two-week period with each egg being laid about 24 hours apart.
If the hens are being kept with a rooster, most eggs should be fertile and therefore able to grow into chicks. Towards the end of laying their clutch, the hen produces a hormone (prolactin) that causes her to become broody. This means that she will stop laying eggs and start sitting on the nest to incubate the eggs. The eggs will not begin to develop until they have that extra body heat from the hen or from an outside source if they are being incubated separately. This is usually around 37°C (100 °F).
The developing embryo will continue to use the yolk and egg white as food sources while it’s building the body parts of fully formed chick. On about Day 19, the chick will use its egg tooth to begin the “pipping” process first by pecking a hole in the air sac (internal pipping) and then by pecking a hole the eggshell and gradually making it bigger until they are free from the shell (external pipping). This entire process, also called hatching, can take up to 24 hours to finish.
Chicks do a lot of growing and changing over their first 8 weeks of life that we tend to divide into four main phases based on their care needs:
During the first week of life, chicks need to learn the basics of survival – eating, drinking, and staying warm. If they don’t have an adult bird as a role model, you may need to help them out by placing them near the feeders and waterers, gently dipping their beaks in until they catch on to the idea. Baby chicks are very fragile at this stage and need to be handled with a lot of care.
During this phase, the chicks start having their first complete moult (losing and replacing all their feathers) which makes them look a little scruffy. They may want to start exploring their environment a little more as long as they don’t get too far away from their heat source for too long. They should be eating and drinking on their own without any problems and it’s a good time to start getting them used to being handled and touched by people.
By the end of Weeks 4 and 5, chicks are finishing their first moult with feathers that look much more like adults. In this phase, they are also starting to learn more about social rules and developing their own pecking order. They should be at least three times the size as when they were born so will likely need to have more space and to have their feeders and waterers raised to a better height.
This marks the transition period for preparing chicks to join the main flock in the coop. As long as its warm enough outside, their extra heat sources can be removed and chicks can have some supervised opportunities to start exploring the coop environment. The chicks will also start going through their first partial moult to replace more feathers.
By Week 8, the chicks are large enough that they can be moved into the main coop with everyone else, but need close watching in case they start getting picked on for their size.
The pullet stage is the chicken version of being a teenager where they are going through puberty and still developing their adult features. They will undergo two more partial moults (one at 12-16 weeks and one at 20-22 weeks) where they develop their final adult feathers. Roosters will have pointed saddle feathers and long sickle feathers as well as much bigger combs and wattles around their face. The saddle feathers on hens are much shorter and rounder.
Most laying breeds of chickens will come into lay at around 18 weeks of age whereas dual-purpose breeds may not start until 22 weeks of age. This may be earlier if they reach maturity during periods of increasing sunlight (spring) or later if they reach maturity in early winter. Since pullets are about two-thirds the size of adult hens, they are generally lower in the pecking order and can sometimes get bullied.
Once a pullet has laid her first egg, she is called a laying hen although she will not technically be considered fully mature until 6 months of age. It is not unusual for the eggs produced by a laying hen in her first cycle to be smaller or have a different shape than you would expect for the first few weeks to months depending on the breed and feeding regime. Some of the commercial egg laying breed like Hylines will start producing normal sized eggs by about 30 weeks of age. Other heritage breeds may lay smaller eggs throughout their lives since they have not been genetically selected to produce large eggs.
When the daylight starts getting shorter in autumn, hens without exposure to artificial lights will start laying fewer eggs and may even stop completely for a couple of months. At 18 months of age, they will start having an annual moult during around this time period where they lose their feathers. This allows them to replace worn or damaged feathers. This break from laying also allows them to repair their reproductive tract and stock up on calcium again for the next laying period.
The number of eggs that a laying hen will produce in the first year can also vary by breed and nutrition. Commercial breeds like Hylines and Shavers that are being fed an appropriate diet and kept in housing with constant daylight hours can easily produce 250 to 300 eggs. Most heritage breeds and cross breeds typically produce around 100 eggs in their first year, but this can be significantly less if they go broody or significantly more (up to 200 eggs) if they are fed and housed correctly.
After the first year, the total number of eggs produced by laying hens will gradually decrease by about 10 to 20% per year until they completely stop laying at around 5 to 6 years of age. If you are purchasing or re-homing an end-of-lay hen who has been retired from a commercial flock, she will generally be about 18 months of age and potentially give you another 3 to 4 years of good egg production.
Hens that have stopped laying still have an important place in the flock as a companion that brings joy to the family. As hens get older, you may notice the signs of aging that include more wrinkles and duller skin around their face, paler skin on their legs, and a decrease in energy levels. It is important to keep a close eye on them to make sure they are still have a good quality of life. Check out our End-of-Life section for more information on what to do if you are worried that your hen may be nearing the end of her natural life.
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