Pre Fiskaraksjonen - vision

12.01.2015 05:21

The below text was made after Aggregat II for Trollheim Kraftverk was decided to have a full investigation by NVE, i. e. during a period of pre Fiskaraksjonen in year 2000. However, chairman Bröske discontinued this work within the 'Surna Group'. Today Surnadal and Rindal Kommune, Elvalag, Samarbetsorgan and Fiskaraksjonen have responded alike to the revision of the regulation of Surna.


Extra reading,

Uppstream - Salmon and Society in the Pacific Northwest, National Academic Press, ISBN 0-309-05325-0

Animal Physiology, Knut Smith-Nielsen, Cambridge University Press, ISBN 0 521 57098 0


On a Vision for the Future Management of Surna.


The Atlantic Salmon has shown a serious decline since the mid 1900. Norway and the river Surna are no exception. To change the course of management the landowners of Surna has taken initiative to an advisory group, The Surna Group, where representatives for interests in Surna can agree upon actions to restore the Salmon. One of the first tasks for the group is to establish a vision that shall describe the goal, the scientific principles and policy for the management of Surna. The strategies implemented in the vision will help identify problems, initiate investigations and assessments, restoration and monitoring, etc. There is often not enough time and resources, and a vision will help to structure the work.


Background for the vision.

The Salmon is an indicator for the condition of many species, the valley, river, fjord and the sea. Normally, the number of returning Salmon experience a decal variation but the steady decline of Salmon in each cycle since the mid 1900 is wrought on by humans.

Each phase in the life cycle of the Salmon is a preparation for the next. Different habitat and phases are coupled and effects the salmon’s performance over its entire life cycle. The Salmon does vaguely know what is waiting in the next phase and habitat. Conditions vary (predators, flow, temperature, food, type of habitat, etc) over the years and different actions and timing are required for survival. The Salmon has solved this by genetic variation. Some grows faster, are less active, more aggressive, and chooses different timing for leaving and entering the river, etc, which gives some the ability to survive through the life cycle. We have therefore chosen a holistic approach for the salmon in Surna. A vision based on ecological principles where the salmon’s whole life cycle with habitats is considered for the management of Surna. 

A river is a dynamic system that constantly changes. Water flow, temperature, seasons, and other varying factors see to that biodiversity and bioproductivity are maintained. Diversity also means a variation in life history, or survival history. Different abilities are supported and trained, and the salmon population has more possibilities to survive. During a regulation or other human alteration the environment is stabilized, or simplified, to a limited variation of life history. The habitat supports fewer abilities and the salmons that survive represents less diversity. The salmon’s chance to survive the next habitat in the life cycle has decreased.

The number of returning salmon should be compared to the governing conditions, primary in the sea. A small return can be a good one if the conditions are bad. On the other hand a fair return is not good during good conditions. There is no procentual relationship between the return, or survival, of salmon to the number of leaving smolt but there is a connection between the conditions in the sea and the river through the sea currents effect on the climate. In general stormy and rainy years seem to be positive. It gives warmer winters and exchange between the upper water layers in the sea, and longer summers with more high water in the river, i.e. longer grow seasons with more nutrients. Bad and god years often coincide in the sea and river, which increases the variation of returning salmon. Good years in the river produce more smolt with more diversity and there are more possibilities in the sea to survive, and vice versa.

Two phases during the first 6-8 months in the sea can be important for the returning salmon. When the smolt is adjusting to saline water and is easily prayed upon, and that the postsmolt must grow up to a minimum size to physiologically cope with the hard winter conditions in the sea. Variations in size, timing, routes, energy consumption, etc, are important during bad conditions, when the “survival window” is narrow. Diversity assures that some of the salmons have the ability to survive and governs the salmon population’s sustainability, is the salmon’s protection against variable conditions. 

The number of returning salmon in each decal cycle is decreasing. We are convinced that it is loss of diversity that is the general cause for this decrease. The seas varying capacity has a large effect on the number of returning salmon but the river is vital to the salmon population because there are reproduction and the major upholding of diversity, which enables the salmon to return from the sea.


Restore diversity.

We can turn the negative trend of returning salmon by restoring Surna and its biodiversity and bioproductivity. The rivers health is dependent on the timing and the magnitude of processes like flow variation, base flows, temperature variation, sediment transport, etc. These processes couples and governs the habitats diversity and productivity. Significant for a healthy river are variation in water flow, functioning coupling between river, riparian zone and ground water, balance between water flow and sediment load, space in the substrate, balanced growth in the riparian zone, etc.

History shows that stocking has not increased the sustainability of the salmon. It is hard to assess when to release young salmon into the river. The degraded river habitat may need 1-year-old salmon for them to survive but the salmon may die in the sea because the environment in the hatchery has produced a too narrow diversity. It is not enough to have genetic variation, although it is necessary. It is genetic variation and variation in life history that together creates diversity. Diversity must thus be given the chance to develop.

We can restore Surna if the will exist. We understand that by using natural processes to restore Surna the risk for new lack of diversity is minimized.


Principles for the vision.

1/ The groups fundamental responsibility, the ecosystem, is Surna´s catchment basin. Restoration of Surna shall be managed according to scientific and ecological principles.


2/ The quality of the habitat effects directly or indirectly the salmon´s survival over its entire life cycle. The management of Surna effects the salmon’s survival in the sea.


3/ The management goal is to limit factors that hinder biodiversity. Diversity governs the salmon population’s sustainability and is the salmon’s protection against variable conditions.


4/ Biodiversity and bioproductivity in Surna can be restored by removing obstacles for natural processes in the ecosystem.


5/ The Surna Group’s goal is to establish a balance between economical and biological activities in the ecosystem. The salmon is recognized as an economical factor.


6/ Restoration of biodiversity and bioproductivity in Surna can only be achieved through the co-operation between different interests in Surna (moral, cultural, biological, economical, etc), local and state government.  





Erik Degerman, Ingemar Näslund, ”Ekologisk Fiskevård”, Sportfiskarna, 1998,

ISBN 91-86786-32-6


Interagency Stream Restoration Working Group (FISRWG)(15 Federal agencies of the US.), ”Stream Corridor Restoration: Principles, Processes and Practices.”, 10/98.


Stanford, J. V. , et. al., ”A General Protocol for Restoration of Regulated Rivers”, Regulated Rivers: Research & Management, vol. 12, 391- 413, 1996.


Independent Scientific Group (ISG) “Return to the River”, North West Power Planning Council, 1996.


Derek Mills, “The Ocean Life of Atlantic Salmon”, 2000, ISBN 0-85238-271-5

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