The sounds of biodiversity, captured in real time

Victoria’s Department of Environment and Primary Industries (DEPI) has been working with an electronic product developer and a soundscape ecologist to create a system that can calculate a farm’s biodiversity by remotely recording and analysing the collective sound insects and animals make in the natural environment - biophony.

The challenge

The impetus for this innovation lay in DEPI’s need to document the environmental sustainability of Victorian farms, according to David Williams, a Principal Research Scientist in the department. Victoria is the biggest food and fibre exporter in Australia, and this move would help bolster the strength of its agricultural sector, valued at $8 billion a year.

The need to measure biodiversity led Williams to the work of Professor Stuart Gage from Michigan State University in the United States, who has developed acoustic indices and algorithms that measure the amount of energy in each frequency range and from that calculate an area’s biodiversity.

Inspired by biophonic measurement of biodiversity in US water catchments, Williams decided to apply an acoustic index.

“I was interested in using the index to demonstrate how good the agricultural production system was in terms of biodiversity, so we got some money from DEPI to do a pilot study,” Williams says.

However the study led to an enormous amount of acoustic data collected from a recorder left in the field, and no fast way to upload it and begin analysis.

Armed with the study results and his technology requirements, Williams successfully bid for $1.5 million from the Market Validation Program. His requirements were for a cheap and robust automated sensor system that would monitor biodiversity via sound. The sensors, which would record the data, needed to be deployed in a production orchard and networked with data collection that would be managed remotely.

The solution

The successful design came from Procept, a Melbourne-based company that specialises in embedded systems and had a track record of delivering technology innovation in health, mining, defence and science.

“The biophony project allowed us to really apply some of our intellectual property around wireless technology, hardware design,” says Procept Managing Director Aaron Maher.

The system includes up to ten sensor stations, which record and store high-definition audio. A dual-band mesh network, operating at 2.4 GHz and 900 MHz, allowed the data to be transferred over large areas by hopping through the network to a gateway, which automatically uploaded the captured audio to a remote content server, accessible via a website.

“The complexity is really the transfer of high-definition audio around a wireless network that can span kilometres, as well as able to transfer back to a server and process all of that in a format that scientists can use,” says Maher.

Where to next?

This is only the beginning, according to the collaboration partners.

“With the way we have recorded this data, you can get a sonic fingerprint of what’s out there. So you can, in theory, teach the computer to identify signals down to a species level,” says Williams.

With this capability, he says, the department will look at the possibility of identifying predatory animals, exotic incursions and endangered species, though for the moment it is concentrating on further biophony research in different vegetation habitats.

Gage is also excited about the research possibilities that the automated biophony system will open up, “Scientists often take ages to get meaningful information to the decision-makers, and we need

to do it in a much more timely and user-friendly way. This system makes it feasible to assess ecosystem health in real time.”

For Maher, “It has opened up potentially a multi-million dollar business,” he says. “We have found that this system applies to so many industries - mining, defence.”

[LINK TO www.procept.com.au]

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