Scarecrows may be outstanding in their field, but now scientists have created an unusual floating version that could help reduce the number of vulnerable seabirds caught by fishing nets.
The device, known as a looming-eyes buoy (LEB), and developed in collaboration with engineers from Fishtek Marine, was trialled in Küdema Bay, Saaremaa island, Estonia, on long-tailed ducks. It uses bright eyespots and looming movements to act as a natural deterrent, preventing seabirds from diving into gillnets – vertical nets used in small-scale fisheries in many countries.
Publishing their findings in the journal Royal Society Open Science, the scientists – from BirdLife International and the Estonian Ornithological Society – found the device to reduce the numbers of birds by a quarter within a 50-metre radius of the buoy.
Yann Rouxel, lead author of the study, and project officer at the BirdLife International marine programme, said: “Unfortunately seabirds can drown if caught up in the nets. We thought if we can reduce the chances of seabirds from diving too close to gillnets, we could prevent deadly interactions from happening.”
After 250 hours of observation, the team found LEB devices could reduce long-tailed ducks congregating between 20-30%, compared with traditional fishing buoys. The birds also came back to the area even after the buoy had been removed, suggesting that they were not permanently deterred.
It is hoped the device, still in its prototype phase, will be tested in small-scale fisheries and help save thousands of seabirds each year.
Rouxel said: “There have been many, many attempts to try to find a solution. Nothing seemed to work across different fisheries and species, so we wanted to try something different, and explore something that will work above the water, instead of underwater.
“We know from experience that direct confrontations … could be counter productive, and we have proven through other programmes that collaborating with fishermen could bring really good results.
“If we can keep the birds away from the real vicinity of the gillnet, if they don’t dive too close, the risk of bycatch is limited.”
Bycatch – the catchment of marine organism not targeted by fishermen – remains one of the biggest threats to ocean wildlife. According to research, at least 400,000 birds die in gillnets each year globally.
Dr Alex Bond, the senior curator of birds at the Natural History Museum in London, said it was “really promising” to see these devices used as a way to reduce bycatch.
He said: “The idea that you can put up what looks like something from Wall-E or some other Pixar film to keep the birds away from where they might come into contact with the nets is great.”
In the past, black and white contrasting panels on fishing nets, and LED lights “almost in the shape of a banana”, attached to the nets were used to drive birds away. For Bond, the googly-eyed devices are an inexpensive way to reduce bycatch.
“It’s relatively cheap, it’s relatively robust, the birds come back when you remove it. The big catch now is to see how it works in small fisheries.”
Madeleine Goumas, a researcher at the University of Exeter’s Centre for Ecology and Conservation, said: “Fishing is a hugely problematic industry for marine animals, and many different species, from dolphins to birds, get caught in fishing equipment as bycatch in the UK each year.
“A wide range of animals show a fear of direct eye contact and even just of model eyes or eye-like spots. It’s interesting to see researchers using this as a way to deter birds and that there might be some promise in reducing the numbers of individuals caught.
“One potential issue might be that the birds habituate to the device over time, especially as – unlike real eyes – they presumably don’t follow movement, so it may be that other strategies need to be considered in tandem.”
