With a special voice, Arturo Elosegi answers Eli Pagola’s questions briefly and precisely. We recommend that you hear the whole conversation:

Healthy rivers bring many benefits, according to Arturo Elosegi. And yet, this is not the main argument he believes there is to recover the rivers: "For me, the main argument for nature conservation is not good or bad. I think that is our duty. Our obligation. We can say this in two ways: we have no right to destroy species evolved over millions of years, or we have no right to leave our descendants a much poorer world than we have lived. But it is true that the healthy river can bring many benefits: for example, in salmon there was huge production in the rivers. This has not been known here in the last centuries, but it has been in the United States or Canada, where prey are being dismantled to recover that wealth. And you see that yes, the fish population has increased. In addition, natural rivers provide clean water and their cleaning capacity is enormous. And on the other hand, sitting on the edge of a river and seeing the water go through, and seeing the sound it does and the fish up and down -- that's going to cost a lot, right? It blinds a lot, and most of the rivers we have today are pretty sad when compared to that."

Damage caused by dams

Pagola tells Elosegi of the damage that dams cause in rivers. This explains why in Europe there are more than a million dams, in Gipuzkoa almost a thousand. "Rivers are completely divided. The problem is not that salmon cannot migrate on its own, no, no, none of its river section. And it's imperative to move through the rivers. Before or after, we know that in any river there will be a serious drought or a phenomenon of pollution and that some population of it will be lost and can only be recovered if its inhabitants can move around. And that causes a small dam to close a very large part of the river and prevent recovery."

Another damage caused by dams is the reduction in the "self-purification" capacity of rivers: "This inert water in dams releases methane, releases greenhouse gases, degrades the habitat... there are a thousand reasons. For example, the prey is filled with sediments and below it there is a lack of sediment. Consequently, in the Atlantic Basque Country it is frequently observed that the streams are "fitted".

The lack of sediments is causing deltas to disappear on a larger scale than the rivers of the Basque Country: "The Ebro is a well-known case, the delta shrinks due to the scarcity of sediments. The city of Jakarta in Indonesia is in a delta and is about to move because it will flood."

The plan for the demolition of dams in Europe is underway. He also explains that there is a movement of "naturalization" of rivers: "on the one hand, dams are demolished. On the other hand, we are trying to recover the riverside forests. Thirdly, for example, we have been in Vienna aware of the enormous work being done on the Danube River, a critical river for navigation which, however, large fragments are being analysed. In the Netherlands, the flooding plains on the Rhin river are recovering, with an increasing risk of flooding and an increasing economic loss. They've seen that they can't go on like this, that they have to go back: as far as possible, get away from the river, let it get out of its way and spread, and protect the neighborhoods, make sure that that water doesn't reach some neighborhoods."

Key species

Elosegi explained that some river species are "representative" and other "keys". Those that require high water quality or high habitat quality such as salmon and trout are significant. Others are key, because they have a big influence on the river, like the beaver: "In Euskal Herria they are in the South and are expanding. In the past we already had them and it has a huge influence on a river whether or not we beaver. In fact, they make dams, they totally modify the morphology of the river, its functioning."

In order to recover some species in the rivers, it is common to have populations from crops to streams. Pagola asks about this and Elosegi says: "When the population is in a very poor state, it is essential to repopulate, but it is not good to rely on that alone. What we have to do as soon as possible is to improve their habitat so that this population stays alone." He explains that nurseries have a big disadvantage: "When we keep any population in the nursery, we domesticate it. And the ones that persist are individuals with characteristics that enable better maintenance in this nursery. But they're often the worst to keep out."

As an example, the European mink: "It is one of the key species in the Basque Country. It is very threatened worldwide, we have one of the best populations in Europe, the Basque, especially in the Ribera Navarra, but it also reaches other areas. And if there are several breeders of this species, and what you've seen is that these loose animals have a very bad future, they're very stupid. In fact, they are the ones that best adapt to the crop, but then the ones that worst adapt to the mountain." Pagola asks if you can't get the farms around the reality anymore -- "More and more are trying to do it, but neither is the best nursery, not nature itself. Sometimes it works, but in the long run we cannot base our recovery plan only on nurseries."

On the measure taken by the government to "recover" the angles: "I do not understand"

Pagola asks Elosegi about the angles. In particular, the measure taken by the Government to recover this species, to professionalise its fishing. Elosegi: "I don't understand. Clearly the species is in a very serious situation. Its decay is very rapid and it is thought that this march will be destroyed in one or two decades, it will be lost, not only from Euskal Herria, from all over the world or from the Atlantic and then experts have said that long ago we must try to reduce to the maximum all causes of death, and especially fishing". Euskal South Herria is the one that is fished all over Europe for the leisure of the angle: "Theoretically, at least, they could not sell the angle they captured, it was for domestic consumption. And that was banned. But then, some of these fishermen have asked to become professionals and have been given permission for the time being. They have not yet begun to fish professionally, because to do so, a decree had to be made first, to determine how many angles, when and how to fish. And they've gone the season, and this year at least it seems they're not going to fish."

From the scientific point of view, Elosegi finds the government's decision "incomprehensible": "They justify it: well, if they are fishing professionals, they will do it as a sentinel, they will see if the population grows or falls... but that's what Azti does: they do their samplings every year and, therefore, it is not necessary. And if you had to catch something to see how the population is, well, catch it and then release! Catching and selling later is totally in contradiction."

Pagola asks him how to improve the situation of the angle. Elosegi: "The first thing to do is to ban fishing, especially when, as here, there was no sector of society that lived from it. But this is not enough: we have to continue to improve the quality of the water, we have to remove the dams, because this hinders the movement of the eel, we have to recover the habitat -- but we don't know if we can recover it, but what we know is that in this way we will lose the security. Now it's time to do."