People can accurately judge biodiversity through sight and sound
British Ecological Society
image:
High biodiversity forest
view moreCredit: Kevin Rozario
People’s intuitive perception of biodiversity through visual and audio cues is remarkably accurate and aligns closely with scientific measures of biodiversity. This is according to new research published in the British Ecological Society journal, People and Nature.
In a new study led by researchers at the German Centre for Integrative Biodiversity Research (iDiv), the Helmholtz Centre for Environmental Research (UFZ) and the Friedrich Schiller University Jena, participants with no ecological training were asked to sort images and audio recordings of forests based on perceived biodiversity.
The researchers found that the biodiversity levels that participants perceived from the images and audio recordings closely matched the actual biodiversity of the forests.
How we perceive the natural world has implications for our health. Previous research has suggested that it is perceived biodiversity, rather than measured biodiversity, that is linked to our wellbeing.
Lead author Kevin Rozario, iDiv, said: “Because it’s suspected that perceived biodiversity translates into mental health benefits, it’s important to identify what people perceive with regards to biodiversity, what the contribution of the different senses could be, and under which circumstances people’s perception of biodiversity best aligns with what ecologists measure.”
To understand what indicators of biodiversity people were perceiving, the researchers also asked the study participants to sort the images and audio recordings according to any criteria that stood out to them.
Visually, people noticed vegetation density, light conditions or colour. Acoustically, people noticed birdsong characteristics, volume or emotions that the audio evoked.
“Not only are we experiencing an extinction of species, but also and extinction of biodiverse experiences.” said Kevin Rozario.
“We recommend to conserve and restore diverse forests characterised by a variety of tree species and structures to also provide habitats for different vocalising bird species. These conservation measures will have the dual benefit of meeting conservation goals while also increasing people’s experience of biodiversity and therefore likely increasing mental wellbeing.”
In each of the two sorting studies, 48 participants were presented with 57 photographs or 16 audio recordings of forest patches throughout Germany, Belgium and Poland with varying levels of biodiversity.
The actual biodiversity of the forests in the photographs was assessed using a combination of four commonly used forest diversity indicators: tree species richness, forest structural diversity, understory structural diversity and understory abundance. Actual biodiversity in the audio files was measured via bird species richness.
In the study, the researchers asked participants to sort the images and audio recordings based on anything that stood out to them when looking at or listening to the forest stimuli and then sort them based on perceived visual or acoustic diversity, respectively.
The researchers caution that people’s abilities to accurately perceive biodiversity may be reliant on them being able to directly compare environments with different biodiversity levels. They point to similar studies that found that participants could not easily perceive biodiversity when they were asked to rate one environment on its own.
The researchers also note that the majority of their study participants were university educated women and that future studies could look to replicate their methods with more representative samples of the general population.
-ENDS-
Low biodiversity forest
Study participant sorting pictures
Credit
Kevin Rozario
Kevin Rozario
Journal
People and Nature
Method of Research
Survey
Subject of Research
People
Article Title
Perceived biodiversity: Is what we measure also what we see and hear?
Article Publication Date
8-Jul-2025
COI Statement
Aletta Bonn, Melissa Marselle and Rachel Rui Ying Oh are associate editors of People and Nature, but were not involved in the peer review and decision-making processes for this paper.
Study shows people perceive biodiversity
image:
In this study, the participants categorised the images or sounds based on the amount of diversity they perceived in the pictures and recordings.
view moreCredit: K. Rozario / iDiv
A new study published in People and Nature finds that both sight and sound influence perception of biodiversity, and participants were slightly more accurate when assessing forest biodiversity through sound alone than through sight alone. This interdisciplinary research, led by scientists from the German Centre for Integrative Biodiversity Research (iDiv), the Friedrich Schiller University Jena, the Helmholtz Centre for Environmental Research – UFZ, and Leipzig University, brings together methods from environmental psychology and forest and soundscape ecology.
In a lab-based sorting study, two groups of 48 participants examined either photographs or assessed audio recordings taken from forests with different levels of biodiversity. The participants then categorised the images or sounds based on the amount of diversity they perceived in the pictures and recordings.
The researchers found that perception of visual diversity was predominantly linked to colour, vegetation density, lighting, and forest structure. Acoustic diversity was linked to birdsong, volume, and seasonal cues, such as the spring choruses of birds.
The findings build on a previous study by some of the authors involved exploring forest biodiversity - mental health linkages, in which the researchers showed that perceived biodiversity, rather than actual tree species richness, was associated with short-term mental health and well-being outcomes.
Tuning into biodiversity
In both experiments, the participants’ perceived levels of biodiversity were closely aligned with the actual biodiversity. This suggests that people can recognise variations in species richness and forest structure, especially when provided with other pictures or snippets of audio as reference points. The researchers also found that participants were slightly better at assessing acoustic diversity than visual diversity, likely because the audio recordings contained fewer confounding elements than the forest images.
“Participants were able to perceive differences in forest biodiversity as they compared and sorted either photographs or audio recordings,” explains Kevin Rozario, co-lead author of the study. “Our results suggest that forest biodiversity perceived through the eyes probably depends on variations in forest density and structure, light conditions and colours, while for the acoustic sense people recognized how melodic the birdsongs were, while also physical properties such as perceived loudness and perceived seasonal characteristics of the recordings mattered.”
This knowledge could inform designing and planning environments that both support species richness and make that richness perceptible to people. For example, these findings suggest that effective conservation and urban greening efforts should also consider how biodiversity is experienced through multiple senses. Incorporating habitat elements that foster more diverse bird calls or visually varied vegetation could enhance public connection to nature and support broader conservation goals.
“As cities grow and natural spaces evolve, designing urban environments rich in both visual and acoustic biodiversity could enhance human connections to nature, supporting both conservation and well-being”, adds last author Prof Dr Aletta Bonn, head of the Biodiversity and People research group at UFZ, iDiv and the Friedrich Schiller University Jena.
While the study highlights meaningful insights into how people perceive biodiversity, the researchers acknowledge key limitations — including that further studies with broader demographic representation would help strengthen and refine these early findings.
Journal
People and Nature
Method of Research
Experimental study
Subject of Research
People
Article Title
Perceived biodiversity: is what we measure also what we see and hear?
Article Publication Date
8-Jul-2025
Why it's vital to save Malaysia's diverse
flora
Published : July 8, 2025 -
Korea Herald
KOTA KINABALU, Malaysia (The Star) -- The plant kingdom isn't doing so well with at least 600 species facing extinction in Sabah alone.
These species, which comprise flowering plants and trees, are under threat due to poaching and other human activities, says Sabah Forestry Department director Datuk Frederick Kugan.
"Besides pitcher plants, the other types of flora facing threats are trees and flowers," he said.
Kugan cited examples such as the dipterocarp (timber) which are being logged and harvested while high horticultural demand for exotic plants like pitcher plants and orchids means they are poached in the wild and sold in the black market.
"There is also habitat loss due to plantation expansion," he said.
He also spoke about a small distribution pattern which is being threatened by climate change, especially montane (mountainous) species, adding that this has also contributed to the decline of such species.
Overall, he said, the species are categorized as "threatened" under the International Union for Conservation of Nature list.
The "threatened" category is further divided into CR (critically endangered), EN (endangered) and VU (vulnerable).
In fact, Kugan said that 10 species of CR plants had been marked as possibly extinct -- anisophyllea impressinervia, ixora labuanensis, lasianthus subglobosus, melanochyla woodiana, praravinia gracilis, praravinia neriifolia, quercus pseudoverticillata, semecarpus angulatus, semecarpus sandakanus and syzygium badescens.
The last seen photos of these tree species ranged from 45 to 148 years ago, Kugan said.
"Another possibly extinct species that was part of our conservation project for the last few years is the CR elaeocarpus pinosukii,'" he said.
He said that many search operations were mounted to locate this species at its locality, Pinosuk Plateau or Mesilau in Kundasang, but none had been found.
Kugan said Pinosuk Plateau or Mesilau, as it is known today, is no longer a forest like it was 60 to 70 years ago (when the species was first collected) as most of these areas have been turned into vegetable farms.
He said all these assessments are based on what have been published in the IUCN Red List.
"However, we have thousands of species that have not been assessed yet, especially the non-tree species," he added.
Kugan said that more research and conservation initiatives need to be taken to better protect these species and hopefully, prevent their extinction.
"There must be coordinated efforts between state agencies, private sectors as well as local communities to find solutions on how to reduce impact on flora and fauna with the development that is taking place," he said.
In March, Kugan revealed that the pitcher plant is under threat in Sabah, with seven species listed as threatened on the IUCN list.
Pitcher plants, also known as monkey cups, have over 160 species worldwide, out of which 25 are found in Sabah.
The world's largest pitcher plant, nepenthes rajah, is only found in Mount Kinabalu and its surrounding highlands.
This species can trap not just insects but also small mammals like rats.
A report in March quoting the IUCN said that "deforestation, farming and climate-fueled fires are driving increasing threats to fungi, the lifeblood of most plants."
At least 411 fungi face extinction out of the 1,300 varieties, said IUCN's Red List of Threatened Species.
