Bay Delta Fish Ecolo..

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Transcript Bay Delta Fish Ecolo..

Striped Bass
(Thousands)
1.8
1.5
1.2
Abundance Index
Abundance Index
(Thousands)
Delta Smelt
0.9
0.6
0.3
0.0
20
15
10
5
0
66 69 72 75 78 81 84 87 90 93 96 99 02 05 08 11
66 69 72 75 78 81 84 87 90 93 96 99 02 05 08 11
Threadfin Shad
12
(Thousands)
(Thousands)
20
Abundance Index
Longfin Smelt
18
16
Abundance Index
14
10
8
6
4
2
16
14
12
10
8
6
4
2
0
0
66 69 72 75 78 81 84 87 90 93 96 99 02 05 08 11
66 69 72 75 78 81 84 87 90 93 96 99 02 05 1 08 11
Sacramento
River
Suisun
Bay
San
Francisco
SacramentoSan Joaquin
Delta
San Joaquin
River
Digital Map from
Dr. William Bowen California
2
State University Northridge
Most fishes follow salinities
Splittail
Delta smelt
Cumulative Percent
100
d
Am. sha
d
Thr. sha
s
d bas
e
p
i
r
t
S
n
salmo
k
o
o
Chin
80
YF
60
by
go
y
arr
t
S
r
de
n
u
f lo
gfi
n
Lo
elt
m
ns
40
or
h
ag
St
20
n
lpi
u
c
ns
h
rc
e
rp
e
in
h
S
Marine
species
0
0
10
20
Salinity
30
Kimmerer 2004
3
Most fish food follows salinities
4
5
Variability of Freshwater Delta Inflow
O
N
D
J
F
M
A
M
J
J
A
S
W
Wet Years
-1
Freshwater Flow (m s )
15
D
3
1983 1977
1998 1991
1995 1992
1982 1990
1958 1994
(1997)
10
5
0
Dry Years
0
0
50
100
150
200
250
Day of Water Year
300
350
6
7
1967-87
1988-2000
1982-2000 (DS)
All Years
Source:
Kimmerer 2002MEPS
4
4
Bay Shrimp
Log Abundance or Survival
Higher trophic levels
show many
relationships of
abundance to
freshwater flow
3
Flounder
3
3
2
2
1
1
5
Herring
Am. Shad
2
4
1
3
0
2
3
5
Delta smelt
Longfin smelt
2
4
1
3
0
2
3
1
Splittail
Striped Bass
2
0
1
-1
0
-2
50 60 70 80 90 50 60 70 80 90
High Flow
X 2 (km)
(km )
X2
8
Low Flow
Log Abundance
Lower trophic levels
show few relationships
of abundance to
freshwater flow
1972-1987
1988-2000
2
2
1
1
0
0
Chlorophyll: Spring
Chlorophyll: Summer
4
4
3
3
2
2
Copepod: Summer
1
1
Copepod: Spring
5
2
4
1
3
0
2
Rotifer: Summer
-1
Mysid
50 60 70 80 90 50 60 70 80 90
-2
X2
X (km)
(km)
2
Source:
Kimmerer 2002 MEPS
9
High Flow
Low Flow
X2=74
10
X2=85
11
50000
W
Average Fall Outflow (cfs)
AN
BN
40000
D
C
30000
20000
10000
0
1930
1940
1950
1960
1970
1980
1990
2000
2010
13
Flows are important
but so is geometry
14
Stationary Habitat ---Geometry
Dynamic Habitat --Hydrodynamics, ocean conditions, weather
Biological Conditions
Environment
15
Estuarine habitat conceptual model
(Peterson 2003)
Stationary Habitat
Tidal
and
River
Flow
Production Area
Pelagic
Recruitment
Dynamic Habitat
16
1873 Delta:
Long residence time
Marsh connections
Two rivers connect
to bay
Waterways dendritic
17
Modern delta
Short residence times
Rip-rapped
Cross Delta flows
Rare San Joaquin
connection to bay
Waterways web-like
18
Old Regime
Environmental Drivers
New Regime
Variable, High
Outflow
Variable, Lower
To the west, Variable
Salinity gradient
To the east, Constricted
Complex, Variable
Landscape
Simplified, Rigid
Low, Variable
Temperature
High, Uniform
High, Variable
Turbidity
Low, Less variable
High P, low N
Nutrients
Low P, High N (NH4+)
Few, Low
Contaminants
Many, High
Predation, Fishing
“Harvest”
Predation and Entrainment
Invasives dominate
Edge & Benthic Fishes, Clams,
Jellyfish, Small Copepods,
Microcystis, Aquatic weeds
Natives dominate
Pelagic Fishes, Mysids, Large
Copepods, Diatoms
Not stable
19
Suisun Region
Stationary Abiotic Habitat Components
River Confluence
Higher
Bathymetric Complexity
Lower
Higher
Erodible Sediment Supply
Lower
Many in South, Fewer in North
Contaminant Sources
Many
Fewer
Entrainment Sites
More
Variable Fall Outflow Regime Dynamic Abiotic Habitat Components
Static Fall Outflow Regime
Higher After Wet Springs
Net Total Delta Fall Outflow
Always Low
Higher After Wet Springs
San Joaquin River Contribution to Fall Outflow
Always Low
After Wet Springs, Broad Fall LSZ
Overlaps Suisun Region
Location and Extent of the Fall LSZ (1-6 psu)
Narrow Fall LSZ In River Channels,
Never Overlaps Suisun Region
X2=
85km
X2=74km
Higher After Wet Springs
Hydrodynamic Complexity in the Fall LSZ
Always Lower
Higher After Wet Springs
Wind speed in the Fall LSZ
Always Lower
More Variable, Higher After Wet Springs
Turbidity in the Fall LSZ
Always Less Variable, Lower
More Variable, Maybe Lower After Wet Springs
Contaminant Concentrations in the Fall LSZ
Less Variable, Maybe Higher
LSZ Overlaps Suisun Region
Dynamic Biotic Habitat Components LSZ Overlaps River Confluence
Higher
Food Availability and Quality
Lower
Variable
Predator Abundance
Higher
LSZ Overlaps Suisun Region
Delta Smelt Responses
LSZ Overlaps River Confluence
Broad, Westward
Distribution
Constricted, Eastward
Higher
Growth, Survival, Fecundity
Lower
Better
Health and Condition
Worse
Regulatory Approaches
FWS and NMFS
(with DFG)
Regional Boards:
New discharge
permit for Sac
Biological Opinions to protect
Regional
smelt and salmon:
In place and subject
TMDLs for salt,
to 11lawsuits from
boron and
waterusers
Selenium from
San Joaquin
Bay-Delta Conservation
Plan:
in development
21
Regulatory Approaches
2
SWRCB
EPA
Issued flows report in 2010
ANPR in February 2011
Developing new standards
for San Joaquin flows and
south delta salinity
What should be done
about:
In 2012 will address Delta
outflow requirements
Selenium
Contaminants
Emerging Contaminants
Ammonium
Wetlands
Estuarine Habitat
Migratory Corridors
22
How much water do fish need?
23
24
What Changes As Flow Increases?
Salinity
and X2
FLOW
Location of
Any Salinity
Range
X2
L
S
Z
stratification
25
What Changes As Flow Increases?
Upstream
bottom current
Floodplain
inundation
River
stage and
velocity
FLOW
River
Stage,
Velocity
Delta
Residence Time
Proportion
Diverted
FLOW
26
What Changes As Flow Increases?
Loadings
FLOW
Nutrients
Contaminants
Organic matter
Sediment
Concentrations
FLOW
27
What Changes As Flow Increases?
Adult spawners move up:
Salmon
Green and White
Sturgeon
Longfin smelt
Delta smelt
Splittail
American shad
Pacific herring
Young Marine fish move up:
Starry flounder
White croaker
Pacific halibut
Young fish move down:
Salmon
Longfin smelt
Delta smelt
Splittail
American shad
Striped bass
28
Five Key Points
1.
Environmental flows are more than just volumes of inflows
and outflows
2.
Recent flow regimes both harm native species and
encourage non-native species
3.
Flow is a major determinant of habitat and transport
4.
Recent Delta environmental flows are insufficient to support
native Delta fishes for today’s habitats
5.
A strong science program and a flexible management
regime are essential to improving flow criteria
29
What Changes As Flow
Increases?
+
+
Location of
Any Salinity
Range
River
Stage,
Velocity
-X
2
Nutrients
Organic matter
Sediment
Fish
L
S
Z
-
Salinity
At a
Point
-
Delta
Residence Time
-
Proportion
Diverted
30
Delta smelt habitat abundance in relation to X2
31
Conceptual Model:
Physical effects on estuarine ecosystem
Key
feedback
loop
Physical
Habitat
Zooplankton Benthic
Production Production
Direct
physical
influences
Physical
forcing
mechanisms
Hydrodynamic
Forcing:
Freshwater inflow
Oceanic variability
Wind
Fish
Production
Transport/
Retention
Phytoplankton Microbial
Production Production
Stratification
Inputs
Nutrient
Input
Organic
Input
32
Material flows