the future of the delta fishes. - calfed science program
TRANSCRIPT
The Future of the Delta Ecosystem and its Fishes
Appendix D
Peter B Moyle and William A BennettNovember 12, 2008
BASIC FACTS ABOUT DELTA FISHES AND THEIR ECOSYSTEM• Delta has a diverse fish fauna• There will always be a Delta ecosystem• The ESA gives Delta fish clout• The Delta is poor habitat for key fish
species• The Delta cannot be maintained in its
present configuration• Major change is on its way
Fish fauna 50+ species, over 50% aliens
THERE WILL ALWAYS BE A DELTA ECOSYSTEM
No matter what happens, the Delta will have lots of fish….
Order will slow delta's pumps
Federal judge's ruling will reducewater supply to save 3-inch-long smelt.
A judge's landmark ruling roils Delta watersDELTA FISH HAVE CLOUT
Delta Smelt Ruling Cuts Water Deliveries to Humans
California Reeling From Delta Smelt Ruling
Ruling to protect delta smelt may force water rationing in Bay Area
Headlines, September 1, 2007
10
5010
10010
15010
20010
25010
1967
1969
1971
1973
1975
1977
1979
1981
1983
1985
1987
1989
1991
1993
1995
1997
1999
2001
2003
2005
DELTA IS POOR HABITAT FOR KEY FISH SPECIES
PODStriped bassDelta smeltLongfin smeltThreadfin shad
RECIEPE FOR MAJ0R HANGE (a.k.a. disaster)
• INGREDIENTS– SUBSIDING LAND– RISING SEA LEVEL– MORE FREQUENT BIG FLOODS– WEAK LEVEES
STEP 1: MIX
Elevation (ft)
>8.26.5 - 8.25.0 - 6.43.4 - 4.91.7 - 3.31.0 - 1.60.01 - 0.9-1.5 - 0-3.2 - -1.6-4.8 - -3.3-6.5 - -4.9-8.1 - -6.6-9.7 - -8.2-16.4 - -9.8<-16.4
IntertidalArea
Suisun Marsh elevations
Basic questions Appendix D
• What species are most desirable?– What species do we manage for?
• How are the fishes affected by ecosystem change?
• How will water export alternatives affect the fishes?
• What actions will improve the Delta for desirable fishes?
What species are most desirable?
• T & E species• Native (endemic)• Support fisheries• Estuarine dependent
0 1 2 3 4
DESIRABLEUNDESIRABLE
Delta smeltLongfin smeltGr sturgeonSteelheadSpr chinookW chinook
Largemouth bassCarpWakasagiInland silversideBluegillThreadfin shad
Life History Metric PC 1 PC 2 PC 3
Spawn frequency 0.12290 -0.20717 0.04870
Life Span -0.46604 -0.38186 -0.16339
Size at Maturity -0.48997 0.04263 -0.25761
Fecundity -0.30002 -0.01987 0.17554Anadromous -0.26211 0.52748 -0.15117
Generation time -0.46539 -0.20798 -0.18254
Parental care 0.35633 -0.07910 -0.56904
Temperature 0.04276 -0.38309 0.27890
Salinity -0.02242 0.51485 -0.18810
Habitat 0.15177 -0.26359 -0.61694
Component Loadings
0.4
0.6
0.8
1.0
1 2 3 4 5 6 7 8 9 100.0
0.1
0.2
0.3
0.4
Principal component
Varia
nces
Cum
ulat
ive
varia
nce
Scree Plot
-1.5 -1.0 -0.5 0.0 0.5 1.0 1.5-1.0
-0.5
0.0
0.5
1.0
-1.0 -0.5 0.0 0.5 1.0
-0.5
0.0
0.5
1.0
DSLFS
KS
SBAMS
YFG
STBKSTAGSF
SPTSKR
TPPSCP
MSQSG
WCFLMBBGRSNGSN BLP
CP
PKMHIT
ISS
TFS
DS
LFS
KS
SB AMS
YFG
STBK
STAGSF
SPTSKR
TPPSCP
MSQSG
WCF
LMBBG
RSNGSN
BLPCP
PKM
HIT ISS
TFS
PC 2
PC 1
PC 3
PC 2
ResidentWarm , Freshwater, Aquatic vegetationLonger life & generationsMultiple spawns
AnadramousSalty, Cool, Open waterShort life span& generations
Single spawn
Open-waterLower salinityBroadcast spawnSmaller size
Aquatic vegetationFreshwaterNest buildersLarger size
Longer life & enerationsLarger size, fecundity
Short life & generationsSmall size, fecundity
Fish SpeciesAssemblagesIn the Delta
Fish Groups Are there management clusters?
PCA analysis
• Native smelt– Delta and longfin smelt
• Planktivorous fishes– Mostly undesirable
• Anadromous fishes– Salmon, striped bass, Amer. shad
• Slough resident fishes– Mostly undesirable non-natives
• Benthic fishes– Mixed native and non-native
-0.8 -0.4 0.0 0.4 0.8
-0.4
0.0
0.4
0.8DS
LFS
KS
SB AMS
STAGYFG
STBK
SF
SPTSKR
TPPSCP
MSQ
PKM
HIT ISS
TFS
SG
WCF
LMBBG
RSNGSN
BLPCP
5 3 2 1
PC
3
PC 2
Desirability
Species Clusters versus Desirability
REGIME SHIFT IN THE DELTA~ TRAIN WRECKCONCEPTS TO APPLICATION
Dynamic Systems Behavior
REGIME SHIFT ~ Interplay of
External slow & Internal fastprocesses
RESILIENCE ~ Capacity ofsystem to absorb disturbanceand reorganize to retainoriginal properties
HYSTERESIS ~Ability to reverse regime shiftIs typically much more difficult
0
800
1,600
2,400
Flow
(106 m
3 )Water exports
0
700
1,400
2,100 Salinity
EC (u
mho
s cm
-1)
1976 1984 1992 2000 2008
30
40
50
60
70
Water clarity
Secc
hi d
epth
(cm
)
0.0
0.6
1.2
1.8 Delta smelt Striped bass
POD species
Fish
bio
mas
s (k
g)0
5
10
15 Inland silverside
1976 1984 1992 2000 20080.0
1.5
3.0
4.5
Largemouth bass Bluegill sunfish
Centrarchid species
Summer Trends in Key Ecosystem Components
-3 -2 -1 0 1-1
0
1
2
3
-1 0 1 2-1
0
1
2
3
-1 0 1 2 3-2
-1
0
1
2
-1 0 1 2-1
0
1
2
3
4
76
77
7879
80
81
828384
85
86
87
88
89
90
9192
93
94
95 9697
98 9900
0102
0304
0506
76
77
78
79
80
81
82
83
8485 8687888990 91 9293
9495
9697
9899 000102
03040506
7677
7879
8081
8283 84
85
86
878889
9091
92
93
94
95
96
97
9899
00
01
02
03
040506
76
77
7879
80
81
8283
84 8586
878889909192
9394 9596979899
000102 03
0405 06
Del
ta s
alin
ity (s
urfa
ce E
C)
Water exports (m3 )
Del
ta s
mel
t (kg
)
Inland silverside (kg)
Wat
er c
larit
y (S
ecch
i, cm
)
Delta salinity (surface EC)
POD
spe
cies
(kg)
Centrarchids (kg)
Ecosystem Regime Shift in the Delta ?
Salt Fresh
Fluc
tuat
ion
Largemouth bassBluegillB. waterweedWater hyacinthAsian clam
Overbite clamSiberian prawnJellyfish
Delta smeltStriped bassLongfin smeltSplittailMysid shrimpTule perch
AnchovySurf perchesMarine fish
Conceptual model of desirable and undesirable species in relation to the estuarine salinity gradient and habitat fluctuations
High seasonal and interannual fluctuations
Effects of Delta & Suisun flooding
• Much uncertainty– Water quality, productivity, alien species
• More brackish water habitat• More open water habitat• More habitat diversity • More fish
– More desirable fish?
“Co-Equal” Goals ecosystem and reliable water supply
• Delta ecosystem– Delta Vision: “sustainable environment”– Our report: viability of native fish populations
• Water supply– Delta Vision: “reliable water supply”– Our report: statewide economic costs
4 Basic Water Export Strategies• Through the Delta: current
strategy
• Peripheral Canal: around the Delta
• Dual Conveyance: both through and around the Delta
• No Exports:use other water sources and use less
IEP-EET workshop February 2008
• Survey of experts on Delta• 39 respondents• Rated effects of 7 water management
factors on 4 species• Rated viability of 4 options on 4 species• Appendix E• Used to support decision making analysis
(Appendix J).
Effects of 7 water management factors on 4 species
• EET Most harmful factors:
• Pumping in south Delta, • Reduced Delta inflows from Sacramento
River.
Decision Analysis Appendix J (Jay Lund)
Economic Cost ($Billions/year)
Like
lihoo
d of
Fis
h Vi
abili
ty (%
)
No Exports
Peripheral Canal
Dual Conveyance
Through- Delta
Exports0
20
40
60
80
100
0.5 1 1.5 2 2.5 3
Delta smelt
What actions will improve the Delta for desirable fishes?
• Create natural flow regime• Reduce alien species• Reduce toxicants• Improve San Joaquin River WQ• Reduce entrainment• Create tidal habitats• Increase floodplains• Manipulate islands• Anticipate climate change
Create Natural Flow Regime• Mimic but not duplicate
historic flow regime, including tidal cycles
• Net downstream flows• High annual variation • High interannual variation
– Variable salinity
• Favor desirable species
Reduce alien species
• Prevention• Reduction
– Change environment– Experimental control
STOP THIS TREND!
ALL ALTERNATIVES MUST INCLUDE RESTORATION ACTIONS
• restore desirable fish• increase water supply reliability• high costs
If the ‘good’ fish could choose…
1. Present Delta WORST2. Open water Delta
abandoned3. Partially flooded Delta4. Heterogeneous Delta BEST
Thanks!
0
800
1,600
2,400
Flow
(106 m
3 )
Water exports
0
700
1,400
2,100 Salinity
EC (u
mho
s cm
-1)
1976 1984 1992 2000 200830
40
50
60
70 Water clarity
Secc
hi d
epth
(cm
)
0.0
0.6
1.2
1.8 Delta smelt Striped bass
POD species
Fish
bio
mas
s (k
g)
0
5
10
15 Inland silverside
1976 1984 1992 2000 20080.0
1.5
3.0
4.5
Largemouth bass Bluegill sunfish
Centrarchid species