Areas with low variety of bird species ‘have more mental health hospital admissions’, new research suggests

Areas with lower bird diversity have a higher number of people being admitted to hospital due to mental health conditions, according to new research.

Dr Rachel Buxton, lead author of the study and assistant professor at the Institute of Environmental and Interdisciplinary Sciences at Carleton University in Canada, said the link between species diversity and health is “underexplored” but this study shows that species diversity “can affect mental health at the severe end of the spectrum”.

The findings showed lower bird diversity was a significant factor leading to higher numbers of hospital admissions for mental health conditions.

The researchers said that while income and the presence of green spaces were also strong factors leading to anxiety and mood disorder-related admissions, there were independent “significant associations” between mental health and bird diversity.

Dr Buxton said: “Often we consider nature as representing the amount of green space near homes or the distance to the nearest park, but the link between species diversity and health is underexplored.

“Our study shows that if species diversity can affect mental health at the severe end of the spectrum (hospitalisations), it is possible that the decline in biodiversity across the globe may be intricately connected with our anxiety and mood on a day-to-day basis.”

Experts analysed data from ebird, an online database of bird observations by citizen scientists, to estimate diversity across the US state of Michigan with the team then combining this with hospital admissions for anxiety and mood disorders in the state.

The findings, published in the journal Geo: Geography And Environment, highlight the complex relationship between the disorders and biodiversity crises.

Dr Buxton added that the research shows how it is “critical” that we “take a holistic approach to our mental health and nature” and “restoring diverse bird communities could be one avenue to improving mental health in cities.”

The new study comes after researchers from King’s College London found last year that watching birds or listening to birdsong was linked to mental wellbeing, with effects lasting up to eight hours.

The Institute of Psychiatry, Psychology & Neuroscience (IoPPN) team said at that time that the links between birds and mental wellbeing were not explained by co-occurring environmental factors such as the presence of trees, plants or waterways.

The researchers said their findings suggested that visits to places with a wealth of birdlife, such as parks and canals, could be prescribed by doctors to treat mental health conditions.

They added that their findings also highlighted the need to better protect the environment and improve biodiversity in urban, suburban and rural areas in order to preserve bird habitats.