Salmon and man today

Fly fishing is a beloved hobby for many. Photo: Terje Tingbø.

A river with lots of wild salmon is a sign of a healthy ecosystem. Wild salmon have therefore become a symbol of wild and healthy Norwegian waterways. We have many rivers where wild salmon thrive. But there are fewer wild salmon now than before.

Every year, 100,000 anglers look forward to the fishing season. In the past, it was almost unthinkable for a fisherman to return his catch alive to the river. Now "catch and release" fishing is popular in many places. In some rivers, more than half of the wild salmon are released.

Wild salmon is still food

For many people, eating wild salmon for dinner is an important part of the nature experience and tradition. Wild salmon is still an important food resource for many.

Fewer wild salmon now than before

It has always varied how many wild salmon return to the river they were born in each year. Even the Vikings had laws about salmon fishing to ensure that enough salmon could spawn. Today, the country's best salmon scientists advise the authorities on how many wild salmon we can catch. They have found that there are fewer wild salmon today than 40 years ago. We humans are largely to blame for this. Fortunately, we can repair the damage we have done.

Salmon researchers give good advice

In Norway, we have a council called the Scientific Council for Salmon Management. It is a group of salmon experts. Every year they give good advice to those who decide on wild salmon. They keep track of the status of wild salmon in several hundred Norwegian rivers, and they calculate roughly how many wild salmon come home from the sea each year.

This harms wild salmon

The experts in the Scientific Council for Salmon Management believe that these things harm wild salmon the most. The most serious is at the top.

Escaped farmed salmon and salmon lice harm wild salmon the most

Salmon farming is a large and important industry in Norway. Salmon lice are a natural parasite that thrives where there is a lot of salmon. Although fish farmers are doing a lot to get rid of salmon lice in their facilities, many places have become dangerously high in salmon lice. A small wild salmon smolt on its way to the sea can die if it gets too many salmon lice on it.

Farmed salmon sometimes escape. Some of them swim up the rivers and spawn together with wild salmon. Wild salmon have had 10,000 years to adapt to their particular river. When farmed salmon spawn with wild salmon, they give birth to young salmon that don't fare so well.

Hydropower regulation and other physical interventions are major threats

The biggest interventions in our rivers were made a number of years ago. Many rivers were regulated to provide energy. Other major interventions were made when, for example, roads and bridges were built.

"We can say that much of the damage has already been done. Now we know more, and there's not much danger of us making the same mistakes again. In fact, we are in the process of correcting some of the wrong things we have done.

Acid rain - an old threat that has diminished

Acid rain is rain that is contaminated by factory smoke. It made the water in many rivers acidic and toxic to wild salmon. As many as 25 strains of wild salmon have died out due to acid rain. We are now liming many rivers to make the water liveable for wild salmon. In addition, factory smoke has become cleaner.

Humpback salmon - a new threat we know little about

Humpback salmon is a species of salmon that originally belongs in rivers that flow into the Pacific Ocean. Humpback salmon were introduced into rivers in northern Russia. Now it has spread to Norway. Humpback salmon live in a different way to our salmon, but they spawn in rivers and compete with our wild salmon for space.

Scientists don't know exactly how much the pink salmon affects wild salmon, but they know enough to say that it is a threat.

The salmon parasite G. salaris - a diminishing threat

The tiny freshwater parasite Gyrodactylus salaris (gyro) is known as the salmon killer. If a river becomes infected, almost all the young salmon can die. In Norway, we have worked hard to eradicate this parasite, and we have succeeded in many rivers. Therefore, experts say that this threat has diminished.

Photo: Jannicke Wiik-Nielsen, National Veterinary Institute

This image is actually in black and white. To help you see the details better, it has been colorized. What you see is the attachment organ of the parasite. Notice the hooks!

We make sure we don't fish too much

We have a better overview of how many wild salmon return from the sea, how many wild salmon we catch and how the wild salmon are doing in the various rivers.

To prevent us from fishing too much, there are rules that salmon fishermen must follow. Now we make sure there are enough spawning salmon in the river.