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When Do Birds Breed and Why? Everything You Need to Know!

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cockatiels perching on tree branch

There are more than 700 species of bird that breed and nest in North America and while there is some variance to the exact time, but all species are dictated by factors such as the number of daylight hours, the abundance and expected abundance of food, and even the temperature.

Because some of these factors can vary year on year, it means that there is no set date or even month when birds breed, lay, or hatch, but most wild breeds will lay eggs in spring so that they hatch at the start of summer when there is a plentiful food supply. As the gestation period of a bird is typically only around 10 days, this means that breeding occurs at around the same time and when the weather warms up and food becomes more abundant.

This also means that the young of migratory birds are ready to fly by winter, and it dictates that most birds breed when nights are longer than days.

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Photoperiod

Photoperiod is a term that refers to the number of daylight hours, which is believed to be one of the strongest natural indicators for birds looking to mate and lay eggs. Day length affects hormone levels in male and female birds, and it also dictates how prevalent natural food sources are. Insect numbers, in particular, are determined by daylight hours.

By around mid-January, you will notice an increase in birdsong. These calls are used by males to attract females and by females to respond, and the quality and volume of the birdsong are what attract a female. Even the best-looking males can struggle to find a suitable mate if their song is not up to scratch.

group of birds

Image Credit: SAJE, Shutterstock

Temperature

Temperature is another important factor. As the temperature increases, flowers bloom which, in turn, attracts more insects and other food sources to their blossom. Birds know that warmer temperatures attract food, so they are increasingly likely to breed when they feel the mercury rise a few degrees.

Some years, when there is a particularly warm snap, it can lead to birds mating outside their usual mating season, and if the temperature reverts and becomes colder again, it can leave some parents and young birds struggling because their food source is prematurely killed off.

Abundant Food

Birds know that their young need to eat to survive and that they will need an abundant supply of food themselves to keep their strength up so that they can look after their young. Egg-laying will often coincide with the arrival of certain insects, including caterpillars. By the time the chicks hatch, mum or dad will be able to collect large amounts of food ready to feed the starving and demanding mouths.

When Do Birds Lay Eggs?

It is impossible to say when all birds lay eggs because some birds are different. Most will lay eggs in early spring and will take between two and four weeks to hatch. However, some birds, including the Robin, may nest several times a year, while others can nest all year round.

How Many Times A Year Do Birds Lay Eggs?

Again, some birds are different, but the general rule is that birds will lay eggs once a year, although the process can take several days as most females will lay one egg per day.

blackbird's eggs in the nest

Image Credit: Pixabay

How Long Is a Bird Pregnant Before Laying Eggs?

The gestation period of birds varies greatly. Some birds can lay eggs just a few days after breeding while others may not lay their eggs for several months. Labour usually only takes a few minutes, although some larger birds can endure an hour or longer of labor with each egg.

Do Birds Build Nests Before They Mate?

Birds are efficient animals. This means that they are unlikely to waste their energy and resources building a nest that might not be required. Therefore, most wild birds build their nests after mating to ensure that they need the nest at all.

You might also be interested in: 12 Proven Ways to Attract More Birds to Your Yard

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When Do Birds Breed and Why?

Birds typically breed and lay eggs in early spring. Not only are conditions ideal for mating and nesting, but it means that the young chicks will be born at a time when there is plenty of food around, the weather is warmer, and so that they will have plenty of time to grow and develop the skills they need to survive winter. However, while this is the most common time for breeding and laying, it isn’t true of all bird species. Some may breed and lay in winter, others nest several times through the season, and a few species can lay eggs throughout the whole year.


Featured Image Credit: Pixabay

About the Author Robert Sparks

Robert’s obsession with all things optical started early in life, when his optician father would bring home prototypes for Robert to play with. Nowadays, Robert is dedicated to helping others find the right optics for their needs. His hobbies include astronomy, astrophysics, and model building. Originally from Newark, NJ, he resides in Santa Fe, New Mexico, where the nighttime skies are filled with glittering stars.

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