Vocally dominant Asian songbird ‘could change sound of Britain’s dawn chorus’

Invasive bird’s loud and frequent song ‘could significantly alter the soundscape of Britain,’ researchers say

An adult red-billed leiothrix at a garden bird-feeder in Horningsham, Wiltshire (Phil Mumby)

A yellow and red songbird native to the Himalayas could colonise parts of Britain and change the sound of the country’s dawn chorus, a new study has found.

The red-billed leiothrix is native to southeast Asia, spanning from the Himalayas across northern India and Nepal, much of China and into Myanmar and Vietnam, where it occupies humid forests and dense thickets and shrublands, the researchers said.

A popular caged bird, it has spread to different parts of the world, including Europe, after being released or escaping captivity and then populating in new habitats, according to the study published on Monday in Ibis, the international journal of avian science.

The red-billed leiothrix , which has a rich song, was not previously considered at risk of taking hold in Britain, but recent sightings, including a cluster in southern England, suggest the birds may already be setting up home and breeding here.

The main cluster has been recorded around the Wiltshire-Somerset border, with 10 sightings between February 2019 and May 2021 over a 22 mile-span area. There have also been other sightings in south Wales, Merseyside and Kent.

The researchers, led by Richard K Broughton, an ecologist at the University of Oxford, said global warming and garden bird-feeding may be helping the birds’ establishment in temperate parts of Europe such as Britain.

Increasingly mild winters due to climate change have probably improved the suitability of southern Britain since an unsuccessful attempt in the early part of the 20th century to introduce the red-billed leiothrix into the wild in southern England. Bird-feeders could also be helping them survive over winter, the paper said.

Britain has already witnessed how invasive ring-necked parakeets have benefited from garden bird-feeders.

The potential establishment of the red-billed leiothrix in Britain could have negative consequences for Britain’s native flora and fauna, as it will compete for food with native birds, and can spread exotic plants and infectious diseases.

In Hawaii, for example, the red-billed leiothrix prefers eating non-native fruits, helping to disperse their seeds. It can also carry bird flu, posing a risk to poultry.

The red-billed leiothrix can also be “vocally dominant”, and in northern Italy its song accounts for more than a third of the sounds coming from the region’s bird community.

In Portugal and Italy the bird influenced the singing behavious of native species, including robins, the researchers said.

“Its loud and frequent song could significantly alter the soundscape of Britain’s dawn chorus,” they added.