Where have all the eggs gone?

You may have noticed that the chickens at NRT’s Sheep Pasture slow down their egg production dramatically during the winter months, but have you ever wondered why this change happens? Do other birds do this?

 
At the NRT, we have a little over 50 chickens, who produce a plethora of eggs all summer long and then almost instantly, all the chickens seem to cease egg production at exactly the same moment. As it turns out, this is something that many people who raise chickens notice. Once the cool weather hits and the days get shorter, egg production comes to almost a complete halt.

 All animals, including humans, follow a circadian clock, which is an internal schedule guided by the 24-hours of the day and how many hours of light and dark there are. Throughout the year, the ratio of daylight hours to hours of darkness changes. We see the most hours of sunlight in the summertime and shorter days with less hours of daylight throughout the winter. These changes in light-dark transitions cause chemical changes within animals’ bodies.

For mammals who become inactive during the winter, either by hibernating or going into a state of torpor, shorter days indicate that it is time to start collecting food and upping fat storage within in their bodies. For many birds, the transition of shorter days in the fall is often a cue to start migrating, however; even before birds begin their migration journeys, their bodies have already picked up on the light-dark changes and many birds will begin molting and getting a new set of feathers for optimal flight conditions.

Chickens are a completely domesticated breed of breed who are thought to have been tamed by humans at least 2,000 years ago in Asia! Because of this, they have lost a lot of their connections to the wild world, but they still have a pretty strong internal circadian rhythm that regulates their bodies’ chemical activities. Although chickens do not migrate (not all birds do), they will still molt when the days get shorter and will also stop producing eggs. This is a change that can be seen with all bird species in New England. Even the birds that don’t migrate will cease egg production until the spring when the days are longer and the conditions are more favorable for providing for their young.

Although we miss fresh eggs in the wintertime, we also know it’s an important process in a bird’s life so that the energy that would normally be used for egg production can be used for molting, migration and keeping warm! We look forward to longer days in the spring and delicious eggs from our happy, healthy chickens when the time is right!