The blackbird's melodious tune has been scientifically identified as the most pleasant birdsong, according to a study published in Frontiers in Bird Science. Researchers found that calls characterized by variation, higher pitch, and moderate volume are perceived as the most enjoyable.
Participants in the study rated 123 songs from common German wild birds on a scale of one to five. Blackbirds achieved an average score of 4.52 for their rich, mellow, and flute-like melodies. They were followed by the willow warbler and the blackcap. In contrast, the barn owl, known for its screeching, ranked last with a score of 1.32.
The study, involving 84 participants, also noted that specific acoustic qualities contribute to pleasantness. A narrower bandwidth, greater complexity, higher frequency, and relatively low amplitude were all perceived more positively. Songs that avoided frequencies where human hearing is highly sensitive also scored higher.
Dr. Nadine Kalb from the University of Tubingen suggested that the enjoyment of birdsong may stem from more fundamental aspects than simply recognizing the species. "You don't have to be a 'bird person' to find bird sounds beautiful," she stated. The research indicates that familiarity with birds or their appearance did not influence how participants rated the pleasantness of their calls.
Dr. Christoph Randler, a senior author of the study, commented on the broader implications of bird sounds, noting their contribution to psychological restoration and well-being. "Bird sounds are often considered one of the most enjoyable aspects of spending time in nature," he said. However, he acknowledged that "not all bird sounds are perceived equally positively."
The findings could have practical applications in urban planning and the design of public spaces. Researchers suggested that the results might inform efforts to improve parks and even influence the design of less stressful environments, such as hospital waiting rooms. Promoting conservation of birds with particularly pleasant songs could also be a benefit.
"We might be wired to prefer more variable sounds with moderate amplitudes and frequencies because they signal a safe, healthy and restorative environment where we can relax," Dr. Kalb theorized.
The study acknowledged limitations, such as not testing factors like call rate, which could also impact perceived pleasantness. The research emerges as concerns grow over declining bird populations. Experts have warned that the dawn chorus is becoming quieter across the UK, with familiar songbirds like the chaffinch and willow warbler experiencing population declines. This reduction in bird numbers has led to a "much-diminished event" compared to previous generations, with the dawn chorus described as an "aural shadow" of its former self due to factors including disease and climate change. The greenfinch population in Britain, for example, has fallen by 67 percent since 1979, leading to its placement on the UK Red List for endangered species, primarily due to the spread of trichomonosis transmitted at bird feeders.