New research project to record Shetland’s underwater soundscape from sea farms
Since August, a handful of Shetland’s sea farms have been reaping a different kind of harvest.
Eight underwater microphones, each dangling off mussels ropes or salmon pens, have been collecting the sounds of the sea for a new research project which hopes to better understand the cetaceans around Shetland and the noise pollution they swim with.
“Living on land we don’t have our ears to the water — so there’s this wonderful world below the waves that we don’t usually have access to,” said Volker Deecke, project lead and professor of wildlife conservation with the University of Cumbria. “There’s still a lot to be learnt about what’s down there making noises.”
Funded by the Ecological Citizen(s) Network+, the Shetland Community Acoustic Research Forum (Scarf) will also see composers turn underwater recordings into music and, according to researchers, offer an example for how we study the sea’s noises further afield.
“We now have [recording] devices available to us that are really cheap,” said Professor Deecke. “The main problem now is the cost involved in getting them out into the environment and recovering them.”
To help, Scarf partnered with Seafood Shetland and aquaculture companies around the isles. Until April farmers will set the microphones — around the size of a GoPro in a waterproof case — at sea, then collect them once a week during routine visits to swap out memory cards and batteries.
Our understanding of how whales and dolphins use sound has grown and changed rapidly in recent decades.
Once thought to offer cetaceans basic form of understand their surroundings through echolocation, scientists now recognise a complex combination of sounds used for communication, orientation and hunting.
In the US, the Cetacean Translation Initiative is using artificial intelligence to decode sperm whale sounds, in what could offer a meaningful step to recognising the animals’ legal rights.
Appreciation for the dangers of underwater noise pollution has grown in tandem — from the short, explosively loud sounds of a seismic survey, to consistently rumbling tankers and trawlers.
'Noise pollution is everywhere, but it's something of a hidden polluter as it's not necessarily that obvious to us,” said Richard Sabin, the Natural History Museum’s principal mammals curator. 'Sound affects almost everything [cetaceans] do, because the use of sound has become such an important sense for these species that has been developed over millions of years.”
As well as understanding Shetland’s watery soundscape better — which species can be heard where, how often and for how long — Prof Deecke expects to hear the noises of weather playing out on the ocean’s surface, and for the recordings to throw up some mysteries.
“With a project like this there will be some surprises. Invariably you get one sound and you think — no idea what this is, but let’s try and found out,” he said.
“Barnacles make noises; it may well be that the mussels themselves make a sort of clacking sound as they click against each other, as they’re opening and closing.”
In time, the researchers hope other parts of Shetland’s seafood sector might also volunteer to help with the microphones, such as creel men or other static gear fishers.
Outside the lab the recordings will also be shared with Emily Doolittle, a zoomusicologist and composition lecturer at the Royal Conservatoire of Scotland, and Shetland-based musician Jenny Sturgeon, who has previously wrangled above-ground field recordings into song.
For Ruth Henderson, chief executive of Seafood Shetland, that level of local interest made partnering with aquaculture companies nature.
“Depending on, and caring for, Shetland's coastal areas, the members of Seafood Shetland hold much valuable knowledge in respect of this environment,” she said.
That extends beyond the seafood sector to a growing network of citizen scientist also, added Prof Deecke.
“Everybody who lives in Shetland has some connection to the sea — be it just looking outside, or actually working on the water,” he said.
“I think that creates a very natural curiosity. If you see a dorsal fin sticking out of the sea from your bedroom window, you want to find out what it is.”
That curiosity is almost sated for researchers back at the University of Cumbria, where an algorithm will first scan through recordings to single out likely biological sounds, “then it’s up to us to listen and try and find out what it is,” said Prof Deecke.
So what do the first recordings of Shetland’s seas sound like?
“They're crunching through the computer as we speak,” he said. “I’m really excited to see what we find.”