Connectivity session Transportation of spawners more effective than multiple fish passage facilities in the river Klaralven, Sweden 5th ICRS Symposium 19-24 Nov 2017, Hamilton, New Zealand Marco Blixt, Fisheries Manager Fortum Sverige AB, Hydro
Contents 1. Background History of the river system Research co-operation 2. Research results A holistic approach Salmon traps and catch data Salmon migration and behaviour monitoring 3. Conclusions 2
Lake Vänern and Göta älv drainage basin Salmon and trout in the past Landlocked salmon and large sized lake migrating trout in at least eight tributaries + the outlet Documented max catch records of at least 20 000 salmon and trout in the river Klarälven during the beginning of the 19 th century 3
Salmon- and trout habitat in the Klarälven river system Återstående habitat Förlorade habitat
Krakerud Strängsforsen Munkfors Forshult Edsforsen Deje 5 Forshaga Skymnäs Skoga
6 10 years of research co-operation on Klarälven river between Fortum and Karlstad University (KAU)
Holistic approach Vänern Lake mortality Trap efficiency Forshaga Edsforsen Spawning success Production of young Spawning habitat Smolt production Höljes Downstream passage
KAU s research projects Spawning migration and behavior Below trap at 1 st HEP Upstream of 8 th HEP Juveniles and Smolt Production of wild salmon Downstream migration of wild and hatchery reared smolt Predation in lower River Klarälven Diversion at 8 th HEP Lake Vänern fishing pressure
Historical monitoring data River catch of salmon and trout 1809-2008 25,000 20,000 Large scale hydro projects in 1830s Catches of spawners 15,000 10,000 5,000 Gillnet fishery in Lake Vänern 1860s First dam for hydroelectric purposes 1906 Ten more dams completed 1907-1964 Smolt stockings 1960s to present 0 Year
Catches of salmon and trout in Deje/Forshaga 1854-2016 Counts 9000 8000 7000 6000 5000 4000 First HPP 1906 3000 2000 1000 0 1854 1857 1860 1863 1866 1869 1872 1875 1878 1881 1884 1887 1890 1893 1896 1899 1902 1905 1908 1911 1914 1917 1920 1923 1926 1929 1932 1935 1938 1941 1944 1947 1950 1953 1956 1959 1962 1965 1968 1971 1974 1977 1980 1983 1986 1989 1992 1995 1998 2001 2004 2007 2010 2013 2016 Year 10
KLARÄLVEN History of actions to support spawning and nursery areas for smolt production Period Action 1907-1933 Free migration with fish ladders 1934-1978 Catch and transport of spawners 1979-1984 No actions*) 1985-1988 Catch and transport of spawners 1989-1992 Stocking of fry*) 1993- Catch and transport of spawners *) due to fish diseases 11
12 How many salmons reach their spawning sites?
13 How many smolts reach lake Vänern?
Results from smolt fyke net trapping 2012-2014 Large variation in catches within and between years 40 35 30 25 20 15 10 5 Catch Fångst Flöde Discharge 400 350 300 250 200 150 100 50 40 35 30 25 20 15 10 5 Catch Fångst Flöde Discharge 400 350 300 250 200 150 100 50 0 0 0 0 Large variation in flow Have to lift the net at high flows 01/maj 08/maj 15/maj 22/maj Catch, number 29/maj 05/jun 12/jun 19/jun 800 700 600 500 400 300 200 26/jun 03/jul Catch 10/jul 17/jul 24/jul Fångst 01/maj 08/maj Flöde 15/maj 22/maj 29/maj Discharge 05/jun 12/jun 19/jun 700 600 500 400 300 200 26/jun 03/jul 10/jul 17/jul 24/jul 100 100 0 0 1-May 8-May 15-May 22-May 29-May 5-Jun 12-Jun 19-Jun 26-Jun 3-Jul 10-Jul 17-Jul 24-Jul Discharge, m 3 /s
Telemetry studies show that migration sucess for wild smolt is doubled during periods with spill flows Wild smolts 1.0 2009 2013 Migration success 0.8 0.6 0.4 0.2 Chi2-test, X 2 1=6,19; P=0,01 0.0
Summary - research results 1000 salmons transported annually 47 tons Vänern Lake mortality 20-80 % Trap efficiency Forshaga Edsforsen Depends on when transported (61-87%) Few young (<< 1 /min) Spawning success Production of young Spawning habitat? Migrants (smolt) production Höljes Downstream passage Survival for smolt: 16-30% Survival for post-spawners: 2% Model the system!
Modified β-diverter at Edsforsen hpp (nr. 8) 17
Modified double β-diverter at Edsforsen hpp (nr. 8) 18
Positive trend 1997-2016 1400 Wild salmon 200 Wild trout 1200 1000 180 160 140 800 600 120 100 80 400 200 60 40 20 0 0 19
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Conclusions For Klarälven, the protection of the remaining landlocked salmon population has the highest priority which means that measures that can safeguard this must continue to be the top priority. 10 years of research has showed that the best and most efficient measure to fulfil this is trap- and transport of spawners. 21 Future measures to further strengthen the population includes improved up- and downstream migration/trapping at hpp 1 and 8, habitat optimization and spillage plan.
Thank you for your attention. Questions? 22