Why do birds sing so much in spring?

By Becca Smithers

Spring has sprung, the days are getting longer, the weather is getting warmer, and the birds are getting louder! Why do we hear birds singing in spring after such a quiet winter?

The answer is simple…

Song thrush. All rights reserved: Timothy Smithers.

Song thrush. All rights reserved: Timothy Smithers.

Sex. Male birds are trying to attract female birds in order to make babies, as well as defending their territory from other birds. While we find birdsong peaceful these sounds of spring are really the sounds of birds showing off and arguing.

Spring is the ideal time to attract a mate. It means that by the time offspring have hatched, the weather will be warmer and there will be plenty of food to sustain the whole family. Winter is too cold to start a family, and most of the birds we see in spring are still in their warmer wintering locations.

We hear our native bird species that stay all year round singing in winter, usually defending their territory. But when the days start getting longer, the male birds have a sort of trigger that tells them to start singing for mates. We suddenly hear more birds singing and this only gets louder throughout spring as migrating birds return to the UK to breed.

Birds often have different songs for if they are attracting mates or defending territories. Defensive calls are usually shorter and can sound angry, whilst mating calls are much softer and more tuneful. It is important for birds to defend their territories as this is where they will raise their chicks.

Why does singing help to attract a mate?

Singing is an incredibly energetic activity, particularly for small birds. A bird’s fat reserves can vary considerably throughout the day. They need to make sure they have enough to survive, but too much food makes them heavier and it is harder for them to escape from predators. Birds need to find the right balance ensuring that they have the right level of fat reserves to survive, which can be difficult to do. Sometimes a bird singing may not be trying to attract a mate or defend territory, but is singing off some excess fat. Birds replenish their reserves by eating, but time spent eating is not time spent singing and attracting a mate, there has to be a balance. If a bird can sing loudly and for a long amount of time whilst also maintaining a healthy level of fat, then it shows that they are a fit and strong individual and therefore a good choice for a mate.

Why do we hear a “dawn chorus”?

Blue tit. All rights reserved: Timothy Smithers.

Blue tit. All rights reserved: Timothy Smithers.

The “dawn chorus” refers to the loud level of bird song that we hear at dawn in spring. This is the first opportunity of the day for birds to sing and attract a mate, there is little point singing at night as it would be difficult to find a mate in the dark! In cities you can hear birds singing at night as the street lighting confuses their internal clocks.

The early bird not only catches the worm but is also likely to get a mate. The early risers are the first birds we hear, we can single out their songs and so can prospective mates. Once the neighbouring birds all wake up and begin to sing it is more difficult to tell the songs apart and the individuals get lost in the chorus of bird song. Different species of birds join in this dawn chorus, they are all trying to compete to be the loudest and attract a mate of their species, so no-one gives up until they run out of energy. Each species has an individual song that can be recognised by human ears as well as bird ears, so listen out for different bird calls this spring!

If you hear a bird song or see a bird and you want to know which bird it is, try british-birdsongs.uk to hear different birdsongs, or use the RSPB’s bird identifier to help you find out which birds you have in your garden!

 


 

Free water worksheets

             … sign up for our newsletter

Sign up to our newsletter for all the news on where we are performing, our new shows, the best of our blog, fun activities and our latest special offers.

We are giving away a series of 7 free water worksheets for KS2 and KS3 or simply to have a go at with the kids in your life, when you sign up to our newsletter.

These worksheets contain fun demonstrations, facts and tips on topics such as pressure, surface tension and water saving. Just pop your details in and the sheets will be sent straight to your inbox.

 

Posted in Biology