Once a barn owl starts laying, the nest box becomes a very busy place. Over the next few weeks the female will sit patiently on her eggs, the male will hunt night after night to feed her, and one by one the owlets will hatch. Here's what happens, step by step.
📅 The timeline at a glance
- Day 1: the first egg The female starts sitting on it straight away.
- Every 2 to 3 days: more eggs Usually 4 to 6 in total, and sometimes more in a very good vole year.
- Around day 30 to 32: the first owlet hatches The first chick can be heard peeping from inside the egg shortly before.
- Every 2 to 3 days after that: more owlets They hatch in the order the eggs were laid.
- Owlets around 3 weeks old: mum starts hunting too Once the youngest can keep themselves warm, both parents bring in food.
- Around 8 weeks old: first flights The owlets start making short flights from the nest.
- Around 3 months old: independence The young owls leave to find their own territory.
🥚 Laying the eggs
A barn owl usually lays a clutch of 4 to 6 eggs. They're white, slightly rounded, and a bit smaller than a hen's egg, around the size of a bantam's. They're laid one at a time, usually every 2 or 3 days, so a clutch of six can take a couple of weeks to complete.
Unlike many birds, the female starts incubating as soon as the first egg is laid. She keeps each egg warm, as close to her own body temperature as possible, while she carries on laying the rest.
Why the owlets are all different sizes
Because she starts sitting on the first egg straight away, each egg starts developing on the day it's laid. That means the eggs hatch a few days apart, in the same order they were laid. By the time the last owlet hatches, the oldest may be well over a week old and much bigger.
It might look unfair, but it's a clever survival strategy. If food is short, the older, stronger owlets have the best chance of surviving. If there's plenty of food, the whole brood can make it.
🔥 Incubation: around a month on the eggs
Each egg needs around 30 to 32 days of incubation before it hatches. The female barely leaves the nest during this time. She only slips out now and then for a very short flight and a comfort break, and she's rarely away from the eggs for more than a few minutes.
Her mate is her only visitor. He hunts every night and brings voles, shrews and mice to the nest to keep her fed. If you've seen her grab the food from him in a flash, here's why female barn owls snatch prey from their mate.
Watch for it: during incubation you'll often see the female turning or rolling her eggs with her beak and feet. This keeps them evenly warm and helps them develop properly.
🐣 Hatching
Hatching is hard work for a tiny chick, and it can take many hours or even a whole day. It happens in a few stages:
- The first breath. Inside the egg, the chick uses a small, temporary point on the tip of its beak, called an egg tooth, to break into the air pocket at the rounded end of the egg. For the first time, it can breathe air and start filling its lungs.
- The first peep. Once it can breathe, the chick starts to peep from inside the shell. The female usually answers with soft chittering calls. Research suggests the chick can already hear and respond to its mother's voice at this stage. The peeping tells her that hatching is close.
- Pipping. The chick chips a first small hole through the shell with its egg tooth.
- Unzipping. Over the next few hours, it slowly chips its way round the egg, making a crack all the way round, then pushes the two halves apart and wriggles free.
- A helping beak. Near the end, the mother can often be seen gently nibbling away the last bits of shell. Once the owlet is out, the empty shell is pushed aside close to her.
The first meal
A newly hatched owlet isn't usually fed straight away. It still has some yolk inside its body from the egg, which keeps it going for the first few hours while its lungs fully open up. After a couple of hours, the mother starts offering it tiny morsels of prey, carefully torn up with her beak.
The owlet hatches with its eyes closed and a thin coat of white down. It's completely helpless and relies on its mother for warmth and food.
Not every egg hatches. It's quite normal for one or two eggs in a clutch not to hatch, because they weren't fertile or stopped developing. The female often carries on sitting on them for a while before giving up.
🦉 What comes next
With the owlets hatched, the hard work really begins. For the first few weeks, the female stays in the box to keep them warm, and the male hunts for the whole family. As the owlets grow and can keep themselves warm, she starts hunting too.
Over the next three months, the parents' whole purpose is to turn these tiny, helpless owlets into young barn owls that can survive on their own in the wild. The owlets grow incredibly fast, get their first proper feathers, start flapping and exercising their wings, and make their first flights at around eight weeks old.
⚠️ Please don't disturb nesting barn owls. In the UK, barn owls are protected at the nest under Schedule 1 of the Wildlife and Countryside Act. A nest camera is the best way to watch everything that happens without disturbing them.
You can follow the whole story, from the first egg to the first flight, on our live barn owl nest camera.
❓ Questions people ask
How many eggs does a barn owl lay?
Usually 4 to 6, laid one every 2 or 3 days. In a very good vole year, clutches can be larger.
How long do barn owl eggs take to hatch?
Around 30 to 32 days from when each egg is laid. Because the eggs are laid a few days apart, they hatch a few days apart too.
Why are barn owl chicks different sizes?
The female starts incubating as soon as she lays the first egg, so the eggs hatch in the order they were laid, days apart. The oldest owlet can be over a week older than the youngest.
Does the male barn owl sit on the eggs?
No. The female does all the incubating, while the male hunts and brings food to her.
How long does a barn owl egg take to hatch once it starts?
The hatching itself can take many hours, and sometimes a whole day, from the first peep to the owlet wriggling free.