Many birds die in collisions with wind turbines and power lines. Just exactly how many isn’t known. But bird deaths can now be reduced thanks to a new acquisition by the Norwegian Institute for Nature Research (NINA).
Photo Credit: Roar Blåsmo-Falnes
A cluster of streaks moves quickly across the computer screen. It shows that a flock of birds is approaching. But not what kind of birds.
We get the answer a few moments later. A flock of seagulls fly past us and land on the lake near where we’re standing.
It’s the new bird radar at the Norwegian Institute for Nature Research (NINA) that notifies us about the flock. The radar system is located in Øysand, not far from Gaulosen, where the river flows into the fjord. The bird researchers had a similar device in the past, but this one is a new innovation and the only one of its kind in Norway.
“The bird radar is an invaluable tool for detecting bird activity.”
Bård Stokke, Senior Researcher at NINA
Photo Credit: Roar Blåsmo-Falnes
The device is designed specifically to map how birds use the airspace and records their activity, even in rain and bad weather. Not only can it tell where the birds are located, but it can also show how high they’re flying. It can also indicate whether the birds detected by the radar are small, medium or large in size. It has a significantly wider range than older versions, so it can detect birds flying up to 10 kilometres away.
“The bird radar is an invaluable tool for detecting bird activity. It gives us much better information than in the past about, among other things, bird migratory behaviour,” says Senior Researcher Bård Stokke at NINA.
He has bird-watching binoculars hanging around his neck. In the past, binoculars were the most important tools used by ornithologists and scientists, as well as GPS transmitters attached to the birds.
“The GPS transmitters are a fantastic tool, but they only show the movements of individual birds. With radar, we can follow the activities of flocks of birds simultaneously,” explains Stokke.
Bård Stokke and the other bird researchers at NINA have been given a new tool, a specially designed bird radar that will provide new and better knowledge of bird movements.
Prevents Collisions With Wind Turbines
The radar system on Øysand is currently undergoing testing. Eventually, it will be deployed in places where wind farms will be built. Including those already completed, there will ultimately be 15 different wind farms in Trøndelag. Most are located along the coast, from Snillfjord in the south to Vikna in the north. The impact of the wind farms on different species of birds is something that needs to be investigated before construction permits can be granted. Apart from Smøla, where a wind farm was put into operation in the early 2000s and a significant number of sea eagles and ptarmigan were killed, there has been no systematic collection of data on the effect of wind turbines on birds.
The new radar can help change this.
“We know too little at present. Better knowledge can help us avoid placing wind turbines in a specific location or that turbines should be relocated to avoid collisions with birds or the destruction of bird habitats,” says Stokke, referring to Bremangerlandet in Sogn og Fjordane, where researchers recommended that two wind turbines should be moved in order to protect birds.
Helps Highlight Powerlines
Photo Credit: Roger Meås
The radar will also contribute to better knowledge about the effect of power lines on birds.
The researchers know that power lines can result in bird collisions. This knowledge is based in part on a research project in Ogndalen, where a section of seven kilometres was examined with a dog to establish how many birds had collided with the power lines. The conclusion was that the collisions led to a reduction of up to 10% in the local population of western grouse and black grouse.
To remedy this, several trials have been conducted and initiatives taken to mark power lines, including with ‘pigtails’ wrapped around the lines to increase their visibility.
“We can’t yet say that such marking leads to fewer bird deaths. But what we can see is that the birds change their behaviour. The marking makes them fly around the obstacle, thereby reducing the risk of collision with the power line,” says Stokke.
More Information Needed
Photo Credit: Roar Blåsmo-Falnes
Gaulosen is a paradise for birdwatchers. On the day the Adresseavisen newspaper visited Øysand, there were not as many birds as usual. Only a few weeks earlier, there would have been plenty of geese in the area, as pink-footed geese and greylag geese like to rest at Gaulosen as they migrate southwards and northwards. But during the limited time we were there, Stokke pointed out several species nearby: common goldeneye ducks, red-breasted mergansers, Eurasian wrens, yellowhammers, house sparrows and great tits, in addition to the crows and gulls.
The radar detected them all.
“But is it such a problem if a few birds die?”
“One dead bird tells us nothing about the effect on the population of a species. Similarly, one wind turbine does not have a major impact on a bird population. But a large number of wind farms can. We need more facts - hard facts - which is why tools like the bird radar are important,” says Stokke.
New Findings at Smøla:
Painting Blades Black
Preventing bird mortality is an ongoing challenge for wind farms, and discoveries never stop when it comes to methods of understanding bird behaviour to mitigate mortalities at wind farms.
Roel May, a senior researcher at NINA, suspected that wind farms could help prevent collisions by reducing motion smear. This is the visual phenomenon that occurs when an object is moving so fast it appears to the eye like a near-invisible blur.
According to the U.S. National Energy Research Laboratory report, it might be possible to reduce the motion smear effect for birds by painting one of the three wind turbine blades black. May and his colleagues at NINA decided to test the theory. The team borrowed eight working turbines at Smøla, who co-funded the project, and brought on painters to rappel onto the turbines and coat the blades in mid-air.
They painted four turbines with a single black blade and compared them to four that were left unpainted. They monitored the turbines over a period of more than 10 years, searching the area below the turbines regularly for bird carcasses with the aid of trained dogs.
The results of the study are promising. Painting the turbine blades black reduced bird strikes by 70%. The black paint reduces the motion smear effect by creating dark streaks that make the blades easier to see for birds, giving them time to change course.
This article originally appeared in the Adresseavisen newspaper on 8th November 2019. It has been translated from Norwegian to English and republished here. Click here to link to the original (online) Norwegian language article.
Original Author: Grete Holstad - firstname.lastname@example.org