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Oxbows, Delta Ponds, and Sloughs: Wisconsin’s Forgotten Lakes
Dave Marshall, Underwater Habitat Investigations LLC
Lower Wisconsin River holds scores of off‐channel lakes
• 2007‐2008 SP River PAL River Grant• 2008 Sauk County LCD ‐ Lakes Grant• 2009 Dane Co. Dept. LWR ‐ Lakes Grant• 2009 Crawford Co. LCD ‐ Lakes Grant• 2009‐10 USRWA – River Grant• 2010 Richland Co LCD – Lakes Grant• 2010 River Alliance – Lakes Grant • 2009‐2010 State Wildlife Grant ‐ ER• 2011‐2012 (2) State Wildlife Grants ‐ ER
Wisconsin’s Forgotten Lakes
Floodplain River Surveys 2011‐12
Pirate perch (Aphredoderus sayanus)State Special concern
Mud Darter (Etheostoma asprigene) State Special Concern
Starhead topminnow (Fundulus dispar)State Endangered
Lake chubsucker (Erimyzon sucetta)State Special concern
Weed shiner (Notropis texanus)State Special concern
Slough Fish Assemblage
Slough Shocker
Beavers are slough builders
Delta Pond
Cut‐off Channel Oxbow
Pirate perch
Mud darter
Starheadtopminnow
Floodplain lakes associate species1 Largemouth bass Bluegill2 Bluegill Largemouth bass3 Grass pickerel Mudminnow4 Mudminnow Grass pickerel5 Mud darter Starhead t. m.6 Starhead t. m. Yellow bullhead7 Warmouth Mud darter8 Yellow bullhead Tadpole madtom9 Green sunfish Warmouth 10 Tadpole madtom Green sunfish
1 Bluegill Bluegill2 Largemouth bass Largemouth bass3 Grass pickerel Mudminnow4 Pirate perch Grass pickerel5 Mudminnow Green sunfish6 Warmouth Pirate perch7 Starhead t. m. Starhead t. m.8 Green sunfish Pumpkinseed 9 Warmouth Yellow bullhead10 Yellow bullhead Brook silverside
1 Largemouth bass Bluegill2 Bluegill Largemouth bass3 Grass pickerel Mudminnow4 Pirate perch Grass pickerel5 Mudminnow Pirate perch6 Mud darter Mud darter7 Warmouth Warmouth8 Yellow bullhead Green sunfish
9 Lake chubsucker Yellow bullhead10 Johnny darter Lake chubsucker
2011 2012
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
0 2 4 6 8 10 12 14
Dep
th (m
)
mg/l d.o.
Wood - Norton Slough Dissolved Oxygen Profiles
Norton
Wood
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
0 5 10 15 20 25
Dep
th (m
)
Degrees C
Wood - Norton Slough Temperature Profiles
Norton
Wood
Modified from Amoros and Bornette 2002
Alluvial seepage
Upland groundwater
Flood
High flow
Low Flow
Cutoff channel oxbows become activeflowing channels and scouring occurs
Low oxbow dissolved oxygen occursduring summer high flows, (> 1‐year storm) and reduced upland groundwater flow
riveroxbow
river oxbow
river oxbow
HIGH
MODERATE
LOW
groundwater contaminationscore = 49.76> 30 = HIGHLY Susceptible
Norton Slough 2008
Norton Slough 2011
Sediment deposition wasminimal, suggestingscouring during floodsand no internal loading.
58%
38% 37%
56%
63%
49%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
starhead topminnow pirate perch mud darter
Frequency of Occurrence
2012
2011
Est. Q7,10
97%
67%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
2011 2012
Percent Long Term Median Flow Rates During Floodplain Lake Surveys
24% reduction in woody debris/tree roots in 2012
2011 Mean habitat value = 2.0
2012 Mean habitat value = 1.53
P = 0.01
2012 surveys
2010
2012 drought
Black River Oxbow Lake
Drought impacts most along rivers with aggrading floodplains
Recommendations
Abandon the “shallow wildlife pond only” policies.
Restore depth and groundwater connectivity in selected oxbows.
Consider conservation aquaculture and transfer to re‐establish rare fish species such as State Endangered starhead topminnow to their original habitats.
Expand floodplain buffers to reduce polluted runoff waterand polluted groundwater from degrading oxbows.
Whites SloughLower Wisconsin State Riverway
Case Studies1. Sugar River oxbow restoration
2. Baraboo River off‐channel lake construction
3. Lake Belle View restoration (watershed diversion around former millpond)
1. Sugar River former oxbow excavated
0
1302
0
0 100 200 300 400 500 600 700 800 900
Starhead t. m.
June Flow
July Flow
Aug. Flow
Sept. Flow
Mean Summer Monthly Sugar River Flows
2009
2010
2011
2012
2012
2010
Shallow wildlife scrapes are notsustained during droughts
Sugar River oxbow restorationUnsustainable due to shallow depths
2. Is off‐channel lake construction a viable option for millpond communities?
Boat ramp and parking
Separation berm
La Valle Slough(max. depth = 1 meter)
Separation berm
Fish Migration Restored
120 mile long Baraboo River
Common carp recruitment in La Valle Slough
8885 84
0
10
20
30
40
50
60
70
80
90
100
Secchi Tot. P Chl‐a
La Valle Slough TSI
3. Lake Belle View Restoration
37
13
63
10
65
2
2
167
178
32
6
13
5
69
1
2
2
1
2
14
8
5
1
2
3
0 20 40 60 80 100 120 140 160 180 200
grass pickerel
northern pike
mudminnow
golden shiner
spotfin shiner
sand shiner
common shiner
fathead minnow
bluntnose minnow
white sucker
yellow bullhead
black bullhead
blackstripe topminnow
green sunfish
pumkinseed sunfish
orangespotted sunfish
bluegill
black crappie
white crappie
largemouth bass
smallmouth bass
johnny darter
blackside darter
Iowa darter
walleye fingerling
brook stickleback
2011 L. Belle View Fish transfer
8879
1
16
1 3 2
30
201
132
5 2 1 1
100
0
50
100
150
200
250
2012 Lake Belle View Nearshore Fish Shocking Results
9/2/2012
9/11/2012>
Carp egg/fry eaters
73
6568
0
20
40
60
80
100
Secchi Chlorophyll Tot. Phosphorus
2012 Lake Belle Ville TSI
First year results after watershed diversion
0
0.5
1
1.5
2
2.5
3
3.5
0 5 10 15 20
Dep
th (M
)2012 Lake Belle View Dissolved Oxygen (mg/l)
Profiles
2/17/2012 6/7/2012
7/12/2012 8/8/2012
9/11/2012
mg/l
Lake Belle View Turtle Nest Project