biocomplexity and fisheries sustainability ray hilborn tom quinn daniel schindler school of aquatic...
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Biocomplexity and fisheries sustainability
Ray Hilborn
Tom QuinnDaniel Schindler
School of Aquatic and Fishery SciencesUniversity of Washington
What is biocomplexity
• Biodiversity is the diversity of life forms including species diversity, and diversity of stocks, life histories and morphologies within a species
• Biocomplexity is the “complex chemical, biological and social interactions in our planet’s systems” (Colwell 98)
The Earth is a living, ever-changing planet. Its environment is defined by the interaction of many complex systems that are structured or influenced by living organisms, their components or biological processes. These systems are the source of our sustenance, well being and quality of life. Biocomplexity is the defining property of these systems, resulting in the `whole being greater than the sum of its parts'. The area of biocomplexity that will come to the forefront in coming years is that of interactions of living organisms with all facets of their external environment. In particular, research on interactions involving multiple levels of biological organization and/or multiple spatial (microns to thousands of kilometres) and temporal (nanoseconds to aeons) scales will be of great importance. (Colwell 2000)
Fisheries Sustainability: The Litany• “Most of the world's major fisheries are depleted or rapidly
deteriorating. Wherever they operate, commercial fishing fleets are exceeding the oceans' ecological limits.”
Greenpeace
What is wrong with the litany?
• Most of the worlds fisheries are not collapsed and produce substantial yield
• In the US we are obtaining 85% of the maximum possible yield
• The authors of the Litany argue fisheries management has failed and we need to look for new solutions
We have the solutions in hand
• There are many successful fisheries
• We need to look to the successful examples and learn from them, not look for “new” solutions
Bristol Bay sockeye stand out as a success story in sustainable
biological management• A single management
agency with clear biological objectives
• Good ocean conditions from 1977-1996
0
10
20
30
40
50
1893
1900
1907
1914
1921
1928
1935
1942
1949
1956
1963
1970
1977
1984
1991
1998
Cat
ch in
mill
ion
s o
f fi
sh
A key to this sustainability is management by escapement goal
In escapement goal management the fishery is regulated to assure that a target number of fish “escape” the fishery and reach the spawning grounds, assuring the long term productivity of the stock
Ugashik
0
1,000
2,000
3,000
4,000
5,000
6,000
7,000
8,000
9,000
10,000
1960 1963 1966 1969 1972 1975 1978 1981 1984 1987 1990 1993 1996 1999 2002
Calendar Year
Cat
ch a
nd
Esc
apem
ent
Biocomplexity of the stocks is also a key
• Diversity in life history– Spawning on beaches, in creeks, in rivers– Diversity of freshwater life 0, 1 and 2 years– Diversity of marine life, 1, 2, 3 and 4 years
• Diversity in morphology
Female
Male
Hansen Creek sockeye salmon
Bear Creek sockeye salmon
Beach spawning sockeye salmon
Diversity of Habitats and Geography
• Many different lake systems– different physical regimes
• Different times of smolt and adult migration
• Long term changes associated with Pacific Decadal Oscillation
Large rivers between lakes have stable flows, no bear predation
Often high density spawning
Small streams often have very high density spawning: also high bear predation
Beach spawning occurs where there is upwelling or wind driven currents
Importance of climate
• The Pacific Decadal Oscillation
Warm Phase Cool Phase
http://tao.atmos.washington.edu/pdo/
http://tao.atmos.washington.edu/pdo/
Lake Nerka, SW Alaska
Historical sockeye population dynamics
1750 1850 19501800 1900 20000
4
8
12
Year
Sal
mon
den
sity
(1
000s
/km
2 )
+ fishery catch
escapement
Schindler and Leavitt (2001)
0
5,000,000
10,000,000
15,000,000
20,000,000
25,000,000
30,000,000
35,000,000
40,000,000
45,000,000
1893 1905 1917 1929 1941 1953 1965 1977 1989
Naknek-Kvichak
Nushagak
Egegik
Different systems have been important at different times
Kvichak
0
2
4
6
8
10
1955 1965 1975 1985
Nak/Br
0
2
4
6
8
10
1955 1965 1975 1985
Egegik
0
2
4
6
8
10
1955 1965 1975 1985
Ugashik
0
2
4
6
8
10
1955 1965 1975 1985
Wood
0
2
4
6
8
10
1955 1965 1975 1985
Igushik
0
2
4
6
8
10
1955 1965 1975 1985
Nush
0
2
4
6
8
10
1955 1965 1975 1985
Togiak
0
2
4
6
8
10
1955 1965 1975 1985
Recruits per spawner
Changing perceptions
• In the 1940s 50s or 60s no one would have ever expected Egegik to be the most important system in Bristol Bay
• In the 1970s no one would have expected the Nushagak to be the most important system in the bay
• Many had never heard of the Alagnak!• Not on many maps
Alagnak River
Alagnak
Alagnak river escapements
0
1,000,000
2,000,000
3,000,000
4,000,000
5,000,000
6,000,000
1950 1960 1970 1980 1990 2000 2010
Spatial scale hypotheses
• The role of biocomplexity and response to climate extends to all spatial scales– We know it occurs on Pacific wide scales
• Documented negative correlation between lower 48 and Alaskan salmon productivity
– We see it at smaller scales• At different spawning sites in a stream
• Even within sections of a stream
Nerka Kema Creek
0
2000
4000
6000
8000
10000
12000
14000
16000
1950 1960 1970 1980 1990 2000 2010
Aleknagik Happy Creek
0
5000
10000
15000
20000
25000
30000
1940 1950 1960 1970 1980 1990 2000 2010
The human side of the story
• For all of the excitement over the biological success, the social and economic success has faded
• It was once possible to clear $50,000 in a 6 week season
The human biocomplexity
• The fishing fleet and processing industry is as diverse as the fish
• Diversity of fishing gears
• Diversity of strategies – mobile, stationary, resident non resident, high capital input, low capital input
The fishery
• 2000 drift gillnet boats and 1000 shore based “set net” gill nets
• Fishery from 25 June to 15 July
• Product is both canned and frozen
• Canned market UK and Europe, Frozen Japan
Photo Robert Kope
Photo Robert Kope
Photo Robert Kope
The race for fish
• Is widely recognized as the primary economic problem in worlds fisheries
• In the 1930’s 30 million salmon were caught in Bristol Bay by 2000 sail powered boats
• We don’t need 2000 high powered vessels• State policy is to spread the wealth to as
many as possible
The management system
The Management System
The fish
The fleet
The managers
The biocomplexity of Bristol BayPrice and Revenue
Climate
The potential adaptation of the human system is restricted by
regulation
• Regulations determine how many and what type of fishing takes place
• There is very limited ability to adapt• We expect that “the struggle for existence” will by
default take place within existing regulations• We are modelling alternatives to the current
regulatory structure including cooperative fishing programs as seen at Chignik
General Lessons
• Biocomplexity appears to be important in stabilizing total productivity over a range of spatial scales in both fish and human systems
• Systems that are productive in one epoch are much less productive in other epochs– The lesson is maintain the stock structure– what seems unimportant now may be very important
later
• The regulatory structure imposed threatens the ability of the human system to adapt
Some other examples
• Ecosystems change
• The productivity of different species changes
52
The “worst” fisheries disaster of the last 20 yearsCollapse of the Northern Cod fishery in
Newfoundland
0
100
200
300
400
500
600
700
800
900
1850 1900 1950 2000
Ca
tch
in t
ho
us
an
ds
of
ton
s
Value of fish products landed in Newfoundland
0
50
100
150
200
250
300
350
400
1989 1990 1991 1992 1993 1994 1995 1996
Groundfish
Shellfish
Landed value in New England
$0
$100,000,000
$200,000,000
$300,000,000
$400,000,000
$500,000,000
$600,000,000
$700,000,000
$800,000,000
1950 1954 1958 1962 1966 1970 1974 1978 1982 1986 1990 1994 1998 2002
Gulf of Alaska – Small set of structuring variables operating at different speeds - Whammo!
“If the biota, in the course of aeons, has built something we like but do not understand, then who but a fool would discard seemingly useless parts? To keep every cog and wheel is the first precaution of intelligent tinkering.”
Aldo Leopold Round River
Conclusions
Final Lessons
• Maintain flexible social institutions: fishing communities need to adapt
• This issue has not been on the legislative agenda
• The fisheries crisis is one of governance
• We know what to do: solutions are available
Acknowledgements
• The FRI pioneers who started and maintained 57 years of continuous data– Bud Burgner, Ole Matiesen, Don Rogers
• The staff of Alaska Department of Fish and Game who continue much of the original work and maintain many of the data bases: Lowell Fair, Jeff Regnart, Jim Browning, Brian Bue