Bird song is reaching a crescendo around now, as spring heralds the start of the breeding season and birds are seeking a mate.
Most people find bird song lifts their mood, but new research has shown that it could have even more profound benefits for health with the song of the wren, for example, aiding recovering after stress.
The first results of a global scientific study to investigate the psychological effects of bird songs have been released as part of the UK's National Science and Engineering Week.
The 'Calls of the wild' experiment, organised in partnership with researchers from the Universities of Salford and Surrey, saw almost 2,000 people of all ages rating eight bird sounds for relaxation after stress and mental fatigue.
The beautiful sounds of the wren, greenfinch – both found in the UK – the silvereye and superb fairywren – residents of Australia and New Zealand – and the less beautiful sounds of the jay and the more exotic parakeet, masked lapwing, and cockatoo were used in the study.
The silvereye's call was rated as most likely to help people relax and to recover from mental fatigue (with a mean score of 3.88 out of 6, where 0 is the least relaxing, and 6 is the most), and the sound of the jay as least likely (mean score 0.91 out of 6). Of the four British birds in the study, the wren was rated as the most likely to help recovery.
Researchers also explored whether the bird sounds were perceived differently when people were informed of the meaning of the sounds. Listeners were presented with various background stories for the birds they were listening to; for example, that the bird in question was aggressive, or that it was peaceful and sociable.
When people believed that a sound was the result of a positive scenario, they were significantly more likely to find that sound to be relaxing than if they were informed that the same sound was caused by a negative scenario.
This suggests that it may not just be aesthetics that are important when it comes to our responses to sounds, but also what the sounds mean. Additionally, familiarity may play a role. When bird sounds were presented as resulting from negative scenarios, exotic birds were rated as significantly less relaxing than native birds.
Eleanor Ratcliffe, from the University of Surrey, said: "When we're stressed and mentally worn out, it tends to be beneficial for us if we can reduce feelings of excitement or being on edge. It may be that a novel bird experienced in a negative context is too alerting to be of benefit, whereas a more familiar bird in the same context could be more helpful for stress recovery."
Coralie Young, Communications Manager for British Science Association, said: "There are many possible applications for the 'Calls of the wild' research. We hope to inspire future researchers to look at the impact of bird sound on people in different settings such as schools, hospitals and sports environments."
Celebrity nature lover Mike Dilger was enthused about the results: "You've still got an opportunity to be part of this fascinating global study. It only takes five minutes and makes everyday people part of important research, just visit www.callsof thewild.co.uk."
Researcher Eleanor concluded: "These results tell us that some bird sounds may be better than others in helping people calm down after stress and recover from mental fatigue, and could lead to further research into the calming impact of natural sounds."