In early spring, with melting snow and stronger sunlight, you may have noticed birds chirping earlier?
We have many migratory birds in Norway. With a lot of snow and ice on the ground, cold wind and little food, the birds choose to migrate further south of Norway in the winter. Some migratory birds go to India or Africa, the South Pole, while some choose shorter “holidays” and go to the Mediterranean, northern France or Great Britain for example.
Well-known migratory birds in Norway are barn swallows, terns, starlings, blackbirds, gray thrushes, chaffinch, cuckoos, vipers and terns.
But it doesn’t quite work out for our flying friends.
This BirdLife report from Lista and Jomfuland bird station shows that migratory birds arrive earlier in Norway in the spring. There has been a change in the feature on one day every ten years. Eight out of 30 species that they have examined return significantly earlier. And many of them are becoming fewer and fewer.
What is the reason why the birds are struggling?
- Climate changes.
- Lack of wetlands.
- Agriculture.
- Industry.
- Forestry.
- Light pollution.
– There are complex reasons why the populations of the various species are declining, 40 per cent are on the red list. There are still several things we can do to improve their quality of life.
That’s what Jan Erik Røer tells us. He is a senior advisor at Birdlife and has worked extensively with migratory birds, bird tagging and bird station operations. At Lista bird station, he has been central since 1990 with a focus on monitoring resting birds in the station area.
WANT MORE WETLANDS: Jan Erik Røer believes that Norway must take care of the wetlands we have for the birds, but preferably also restore more. Photo: Private.
Røer says that many wetland areas in Norway have been built over in recent years, and these are very important for the birds.
– There are plans to restore several wetlands, but this work is progressing slowly. It is therefore extra important to take care of the wetlands we have, he says.
– I am worried about all the birds on the red list, for example the vipa, and the hornbill which has been very numerous in the past, the same with auks such as the krykkja which have produced bird mountains full of birds before, he says.
For the migratory birds, it is not just the conditions in Norway that matter. Both during the trek and the arrival area must be able to provide sufficient rest and food. If there is a problem in one of three places, it can destroy a lot.
– Swallows eat while flying, while many other birds are more dependent on filling up before they leave, and stopping along the way to eat.
– For example, the insect-eaters who are going to Africa in the autumn will have problems if it has been super hot in Europe, as it has been for some years. Then there are again few moist areas that provide a lot of food. They need a lot of energy to get across the Mediterranean and then across the Sahara desert.
THE WORLD’S LONGEST MIGRATING BIRD: The red-billed tern migrates from the Arctic to the Antarctic every year, and during its lifetime can migrate a distance equivalent to three times back and forth to the moon.
Why are there birds in Norway?
Røer says that the various species originally had core areas in Africa during the Ice Age, then they moved further and further north, and eventually they found their place in various places in Norway.
– Having wings is very smart, they have good access to food here in Norway in the summer, and there is less competition here. There is an abundance of food, which makes it a good place to nest.
– It is all the tougher to survive the winter here, as you can see with the blue tit, which must have more eggs in the nest than those that migrate far, in order for the population to last through the winter.
Norway is home to the world’s longest migratory bird, the red-billed tern. It migrates from the Arctic to the Antarctic every year, and during its lifetime can travel a distance equivalent to three trips back and forth to the moon.
Another Norwegian bird species, the lapwing, holds the record for the longest non-stop migration. A radio-tagged individual traveled a full 11,000 kilometers non-stop from Alaska to New Zealand. This journey took nine days, and the bird had lost almost half its body weight during the trip.
(Source: NINA)
Migratory birds are caught in Norway
Climate change has also made the winters in Norway more unpredictable, which can fool the migratory birds that stay closest.
– When there are sudden warm days and snowmelt in early February/March, birds that winter in the UK and northern France, for example warblers, can react to these temperature changes and fly north to establish a territory.
They can be caught if the mild weather changes to cold again. They will first try to get through the unexpected cold, but it quickly becomes too cold, and the ground can become rock hard.
– Vipa in particular could be affected by this. If it gets too bad, newly arrived migratory birds can retreat south again. We saw exactly this with the thrush in spring, which had come inland, but went out to the south and west again when the snowy weather came again at the end of March and early April. Flying back and forth like this wastes a lot of energy, says Røer.
There is a big difference in where the different birds go in winter. They have different feeding habits, some want certain types of seeds, fish or insects that they only find in the various places.
Those who are far away in Africa have a built-in clock that tells them when it is time to leave, regardless of the temperature here in Norway.
– For example, the barn swallow has no chance in Norway in the winter since it hunts insects over land, so it migrates south of the Sahara, some all the way down to South Africa, says Røer.
– There are also variations within the species, where some go to the Mediterranean, while others go all the way across the sea and down Africa. They look a bit for where there are others, and where the competitive advantages are favorable. The monk songbird migrates both to Africa, southern Europe and some migrate from Central Europe to England in winter. The raptor, which is found in the north of Norway or east towards Russia, often goes to South Africa, while the same type of bird in Scania does not migrate at all, he says.
LINERLE: The species is found all over the country. Photo: Jan Erik Røer.
WINGER: The wren breeds in Norway most commonly in Eastern Norway and along the coast to Trøndelag, but more sparingly further north. Photo: Jan Erik Røer.
How do they navigate?
The birds have many different tools they use when navigating to the right places. It is different in the different species, but also different in different parts of their journey
- There are many indications that the birds can sense earth’s magnetic field and orient themselves according to it, because the birds have something called cryptochromes in their eyes. They use this to set the rough rate for the trip.
- They can also use infrared radiation. When the sun has set, this will remain for a long time, and the birds can use it because they see it better than us.
- In addition, they use the starsbut modern light pollution over the biggest cities can be a problem in some places.
- They also use land formations. At a certain height, it is easy to recognize what it looks like.
- It is possible they can use both sense of smell and hearing also to recognize smells and sounds along the road.
– In Norway, people have followed the migration of an osprey that has gone to Mauritania, and you have seen that it suddenly goes off course, but then finds its way back again. It has found the same pond along the way in France for several years, so it has used many tools to find it. If one method fails, they can probably use another to find the right way.
– If the magnetic pole were to move very quickly, there could probably be great confusion and chaos. But small changes are probably fine, he says.
He says that birds that migrate far are more dependent on being accurate, a few degrees of error can lead to places without food and resting places. The cuckoo, for example, cannot come up with too much nonsense. It is also about where it will land en route to rest and eat.
WHERE SHOULD THE TURBINES BE LOCATED? With the help of weather radar, you can find out a lot about where the migratory birds fly, and therefore where you should not place wind turbines.
What can we do?
Industrial sites in unfavorable locations can deprive the birds of good wetlands and nice places to nest with good food opportunities. They can also kill the birds directly.
– We also know that birds are killed by wind turbines, says Røer.
But can this be solved with good technology?
The Norwegian Institute for Natural Research (NINA) has started a project where they want to look at just this. By using radars that are used to report weather and wind, they also gain valuable insight into which routes the migratory birds use. For the first time, the tool will be used to map bird migration in Norway. Among other things, this could be important in the planning for where they want to set up wind turbines.
– Most of the birds migrate at night at high altitudes, and often scattered, so we know relatively little about exactly how they migrate in and out of the country. It is very important to know in relation to the construction of all industry, and perhaps especially wind power . The development that is carried out must be sustainable, and then one must, for example, have access to information about how the birds fly over the North Sea. In addition, we should look inland and see where they fly. They need more wetlands and less industry at these rest areas, says Røer.
– This project will be able to point out places where development is less or more harmful to the birds. Then one can ask whether enough consideration is being taken, and whether it becomes an excuse to build more wind turbines than the starting point, he says. In many other cases, a lack of knowledge about migratory birds is not the problem, but rather that authorities and industry often choose the simplest and most affordable solutions, even if it harms the birds.
We are also working on our own radars on wind turbines which will switch them off when birds come.
– But it must be accurate on individual birds as well, not just large flocks. It is a technological optimism that makes the mindset that it will work out. However, all experience shows that new technology and development create more challenges than solutions right from the start, before you learn from the mistakes.
– When the weather is bad, it is also typical for the birds to gravitate towards what they can perch on, so that is also something that must be taken into account. Seabirds can often have important feeding areas around places where it is typical to set up turbines, says Røer.
