Friday, 31 January 2014

Why do birds sing?

Robin by Andrew Malcolm
Birds sing in order to communicate and for two main reasons -
  • to attract a mate
  • to defend a territory
A male bird singing in spring and early summer (and it is mostly males) is proclaiming that he is in tip-top breeding condition and is ready and able to mate. Females in the vicinity are attracted by the song and can judge by it whether or not the singing male will make a suitable mate. She can decide by the quality of his song as to whether he is strong and healthy enough for the rigours of mating and providing food for their offspring.

The singing male is also defending his territory. He is, in strident terms, telling
Garganey by Richard Zamora
other males that this patch is his, as is the female, and to keep well away. Just as the female is attracted to the male's song, other males are repelled by it. This largely avoids unnecessary physical confrontation between males which could lead to injury to either or both. An injury to any wild animal greatly reduces its survival chances. Furthermore, if a male for whatever reason, does not defend his territory, another, probably younger male, will quickly move in and take over.

Song Thrush by Fran O'Connell
Perhaps the best time to listen to birdsong is at dawn, the aptly named 'Dawn Chorus'. Why should birds sing most actively at dawn? At dawn the air has not warmed up so that conditions are usually fairly still and sound carries further. The males are also proclaiming that they are still alive and active and re-asserting their claims to territory and females after the night. It is also thought that feeding opportunities being limited at dawn, the birds can devote their time more readily to singing.

Wren by Fran O'Connell
By mid-July, singing will have very much declined. Most birds will have mated by then and competition for mates and territory will have fallen off. By late summer many species of bird will be in active moult and the last thing any bird will want is to attract a predator whilst their flying ability is impaired.

Skylark by Andrew Malcolm
In addition to singing, birds have a range of other vocalisations. These are used to warn other birds of threats such as predators and other dangers. Many species have contact calls, particularly used in feeding and migrating flocks to keep in touch and in communicating with fledged young. Most of us are familiar with the alarm call of a blackbird when disturbed or the 'tick tick tick' warning call of a robin.

Reed Warbler by Fran O'Connell
Some notable songsters easily heard in Waterford include the skylark with its seemingly endless cascade of song often delivered from high up in the sky. The song thrush is readily heard repeating each phrase of its song over and over again. Listen out for the reed warbler singing from deep cover in reed beds or the very loud song of a wren which seems impossibly vocal for such a tiny bird.

Bird song recordings are easily accessed on the internet and can be downloaded as apps. An excellent and informative book on bird song is 'Bird Watching With Your Eyes Closed' by Simon Barnes which introduces many familiar birdsongs of Britain and Ireland. An accompanying podcast can be downloaded from the internet.
Yellow Wagtail by Bernie Sheridan


The discovery of an adult male yellow wagtail at Curragh Beach, Ardmore was a nice find. Disappointingly the bird departed after a short time, to the annoyance of would be observers. A pair of garganey was seen at Ballinlough near Kill. Garganey are a small duck which interestingly are the only duck species which migrates from the south in Africa into Europe to breed. Hopefully this pair might successfully raise a brood in County Waterford this year. 

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