Why do Birds Sing?

There comes a day when you venture outside and notice the, no longer subtle, changes: it's as if birds have turned up the volume when they sing.

No, it's not your imagination, the birdsong is definitely louder. The days are longer, the air is warmer and the males of the species' thoughts turn to...... Well, it is spring after all.

Although birds make sounds throughout the year, alarm calls and quiet chirps and cheeps, it is in the springtime that the males ramp up the volume. Singing is the bird equivalent of showing off, a proclamation of strength and masculinity and this only gets louder in springtime and as migrating birds return to Ireland to breed..

Even though we, as humans, find birdsong tuneful and uplifting, to birds it is a shouting match. They know they need to get their act together and proclaim loudly if they want to defend a territory, find a partner, build a nest and bring a new generation of baby birds into the world.

Birds need to mate, nest and breed in order to pass on their genes to another generation of sparrows or wrens or hawks and singing, for the male, is part of the repertoire to prove his potential to a female. Singing is an incredibly energetic activity, particularly for small birds. It takes a lot of energy to sing and it proves to any potential female and rival males that this particular male is strong and healthy and will provide for their partner. If a bird can sing loudly and for a long time whilst still maintaining a healthy weight (level of fat), then it shows that they are a fit and strong individual and therefore a good partner for a female to choose

They say that the early bird catches the worm but those early risers are also likely to get the first choice of mate and they are the first birds we hear each morning, the blackbird, the robin and the wren, even individual songs can be discerned and, if we can so, can a prospective female.

Unlike the sounds they make all year, songs are usually very complicated and different species of birds have developed different songs. This enables them to sing at the same time without confusing each other. Once other birds wake up and begin to sing it is more difficult to tell the songs apart and they become lost in the cacophony of the dawn chorus. Since the stakes are high, however, no bird gives up until they run out of energy and have to find some much needed food to replace what the singing has lost..

One theory, as to why birds start singing so early, is that in the early morning, the light levels are too low to do much foraging as many insects are not yet up and about, so it's a great time to sing instead. The lower morning air temperatures and less active air currents allow sounds to carry further without as much interference and his beautiful song may also travel further when there is less ambient noise such as traffic to stifle the sound. The song is not as likely to be drowned out, giving the strong, early singers an advantage because their song will be easier to hear.

Spring is the ideal time to attract a mate. It means that by the time their offspring have hatched, the weather will be warmer and there will be plenty of insect food to sustain the whole family.

Photo credits: Robin - Wildedges: Song Thrush - Tony Philp: Blackbird - Wikimedia: Wren - Paul Miguel