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Is the eel climbing back up the slippery slope?
Overcoming the barriers, how far have we come?
Willem . Dekker @ SLU . SE
Department of Aquatic Resources
Institute for Freshwater Research
Sveriges lantbruksuniversitet
Swedish University of Agricultural Sciences
IFM Workshop 2015 Passage and Screening; overcoming the barriers.
Deafblind Centre, Peterborough, 10-13 Nov 2015
Life cycle
Ocean Continent
Silver eel
Blankål
Yellow eel
Gulål
Leptocephalus
Glass eel
Glasål
Fisheries
0
10
20
30
1950 1960 1970 1980 1990 2000 2010
Pro
du
cti
on
10
00
to
n
Fishery Aquaculture Restock
1
10
100
1000
1950 1960 1970 1980 1990 2000 2010
Ind
ex
AdCP AdTC Albu AlCPEbro Ems GiCP GiScGiTC Imsa Katw LauwLoi Maig MiPo MiSpNalo RhDO RhIj RingSeHM SevN Stel TibeVida Vil YFS2 Yser
Glaseel
1958 1991
C. Puke, Svensk Fiskeri Tidskrift 1955
P.N
ord
be
rg 1
97
7 L
jun
ga
n.
1957: 104 kg
1975: < 1 kg
2015: --- kg
Huningue piscifactoire 1852
Victor Coste 1852
1. Artificial reproduction
Syrski 1874 Freud 1877
Grassi & Calandruccio 1897 Schmidt 1923
Is “the eel problem” now solved?
2. Natural reproduction “the Eel Problem”
0
10
20
30
1950 1960 1970 1980 1990 2000 2010
Pro
du
kti
on
1000 t
on
Fishery Aquaculture Restock
0
50
100
150
1940 1950 1960 1970 1980 1990 2000 2010
Mill
ions r
esto
cked
SE FIEE LVLT BYRU UAPL CZAT HUCH DEDK NLBE UKFR ESIT ??
PL
DE
NL
Hans Lübbert 1908
Mgr. Dąbrowski 1952
Hermann Haack 1871
Baron de Rivière 1840 3. Restocking
Was restocking successful? Has it changed eel history?
4. Technical developments
1852
1874
1908
2005 1998
X. How low can we go?
EU
Uniform protective action
Common actions
- Closed season
- Min. legal size
- Quotum
Distributed Control
Target
2007
Implement
2009 …
Plan
2008
Evaluate
2013
Monitor
2009 …
Assessment
2012
Local management, no protection
National implementation
Local action in the field
Common target
2015
2016
What barriers have we overcome?
Sjöstrand & Sparholt 1996
1850
1870
1890
1910
1930
1950
1970
1990
2010
Animation, stretch, from left
Stock in decline
Artificial reproduction
Biology Sargasso Restocking Restock & develop
Glass eel crash
2020
2010
2000 Scientific advice
EU takes coordination EU Eel Regulation National management plans … put into action 1st evaluation 2nd evaluation
Evaluate the management process
the Eel Management Process…
Problem
Policy
Long target
Short target
Action plan
Evaluation
Status=target?
Declining yield
Glass eel crash
Management plan! (F=0)
30-50%=40%
F:40% (40%)
EMP by area
Monitoring & assessment
Feedback to areas:
where, how much, what to do
30-50%
F=0
EMP: F=0!
none
ICES-WGEEL ICES-ACOM
Search: ICES Journal Climbing back
Environment and History, accepted 2015-Feb-19, publication spring 2016
FAIRE MIEUX QUE LA NATURE? THE HISTORY OF EEL RESTOCKING IN EUROPE
Willem Dekker & Laurent Beaulaton
Search: history faire mieux
Further reading
All for one
And one for all
Nilsson 1996 A-B Ålexporten Åhus.
Canada London Skåne London Åhus Berlin
B0
L = ?Legend
Blim
Bbest
Bcur
L
LL
L
L L
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30
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-1 0 -5 0 5 10 15 20 25 30 35
2012 blankål lekvandring
L
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L L
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L
30
35
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45
50
55
60
65
-10 -5 0 5 10 15 20 25 30 35
nu
bäst
40%
jungfrulig
L = ?
All for one
And one for all
Många bäckar små, gör en stor å
Summing up:
Traditional but adaptive – protection and sustainable use – small scale but biggest in EU – cultural diversity and shared responsibility
