Monitoring technologies commonly mentioned in biodiversity credit methodologies still have limitations that experts should take into account when engaging in nature markets, a study has said.

Published in the Journal of Applied Ecology and authored by scientists from the University of Nottingham and non-profit Operation Wallacea, the report reviewed the most popular biodiversity monitoring technologies, in an attempt to evaluate their readiness to fulfil key requirements for nascent biodiversity credit markets.

As various biodiversity credit methodologies and standards have emerged, market actors are increasingly relying on technologies to measure biodiversity at scale, and ensure corporate claims can be verified.

“New credit methodologies and standards are being proposed within the nature finance market at an astonishing rate, all offering a blueprint to quantify the biodiversity gain or avoided loss from a project,” the study said.

“They tend to involve collecting primary monitoring data at the spatial scales of conservation or restoration projects (tens to thousands of hectares), with reporting on monitoring every one to five years.”

However, while technologies have the potential to enhance monitoring in the following years, they have significant limitations, it said.

TECHNOLOGIES AND GAPS

Authors focused on key tools such as environmental DNA (eDNA), passive acoustic monitoring, camera traps, and other methods mentioned in some of the most credited methodologies available, including those designed by Wallacea Trust, Plan Vivo and Pivotal, Savimbo, Verra, and ERA Brazil.

“Some of these technologies can be limited in obtaining direct, taxonomically detailed measurements … [which] could be problematic for regulatory compliance or biocredit issuance, depending on the specific methodology requirements,” the study said.

For instance, while satellite remote sensing has great potential, it is still subject to environmental conditions, such as clouds that obscure images, and is limited to top-of-canopy information.

On camera traps, a widespread tool for detecting mammals and suitable for a range of habitats, scientists said they may affect animal behaviour and fail to trigger with small animals. Moreover, cameras are at risk of being stolen or damaged, while facing some privacy issues.

As for eDNA, scientists noted that the technology is still too expensive, while its coverage can be limited, and is subject to possible cross-contamination during sampling activities.

“Accuracy and sensitivity of eDNA detection, in particular, are highly dependent on the protocol, the environmental conditions at the site at the time of sampling, and the characteristics of the target species,” the study said.

“This can lead to considerable variation in the rates of false positives and false negatives among different samples.”

Passive acoustic monitoring tools are low cost, but could lead to the collection of a massive amount of data, which would then require storage, the study said.

Furthermore, detections vary with environmental conditions, while acoustic indices are not yet comparable across time and space.

OPTIMISM

As the authors noted, the evolution of AI tools for automated species identification will allow experts to deal with some of the limitations related to acoustic monitoring.

In general, the developments in automation and machine learning will “rapidly make these technologies more accessible and efficient”.

Meanwhile, in light of all these limitations, more than one technique will typically be required at any one time, scientists said, advising experts to combine those with ground validation and human-collected ecological data.

“Emerging financial tools for biocredits, therefore, need to be cognisant of current limitations in these technologies, with a view that these will probably improve in the coming years,” the study said.

“Technological solutions, while not yet a panacea for biodiversity assessments, are vital for the scales the biocredit market requires.”

Co-authors Franziska Schrodt and Richard Field also led an evaluation project of 17 biodiversity credit methodologies, finding significant gaps in how they deal with uncertainties associated with sampling errors, seasonal and day-to-day variation, and other factors.

Of the 17 methodologies reviewed by the team in March, only a few explicitly addressed uncertainty in their documentation, they told Carbon Pulse in June.

By Giada Ferraglioni – giada@carbon-pulse.com

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