Changes in River - Land Uses and Management: Implications for Salmonid Habitat Restoration in the Cedar River, Washington Robert Wissmar and Ray Timm University of Washington

1
Changes in River - Land Uses and Management
Implications for Salmonid Habitat Restoration in
the Cedar River, WashingtonRobert Wissmar and
Ray TimmUniversity of Washington

• Goal Develop societal-ecological approaches
  that can be applied to restoration initiatives
  and management policies at different landscape
  scales

2
(No Transcript)
3
Restoration Studies of the Cedar River

• Part I Changes in Developed Land Cover
  1991-1998, Wissmar et al. (2000)
• Changes in Developed Land Cover, Wissmar et al.
  (2000)
• Impervious Land Cover Assessment, Logsdon et al.
  (In review)
• Changes in Tributary Hydrology, Wissmar et al.
  (In prep.)
• Part II Land Use Influences on Floodplains
  Implications for Habitat Restoration and
  Protection
• Habitat Prioritization, Timm et al. (In review)
• Protection of Riparian Habitats in Erosion-prone
  Landscapes, Wissmar et al. (In prep)
• Part III Habitat Selection by Salmonids, Hall et
  al. (2000, 2002)
• Implications for Habitat Restoration
• Part IV Disturbance Regimes, Habitat
  Interactions and Restoration Across Riverine
  Landscapes, Timm, Ph.D. Diss. (In prep)

4
(No Transcript)
5
PART I Basinwide AnalysisLand Cover Changes
1991 - 1998

• What is the change in developed land cover?
• Identified major locations of changes in
  developed land cover
• Changes in developed land cover layer indicates
  increases in impervious areas

6
(No Transcript)
7
(No Transcript)
8
PART I Basinwide AnalysisLand Cover
Changes 1991 - 1998

• Why do we have patterns of change in human
  development?
• Urban areas (Downstream region)
• Widening of major highway on floodplains
• Conversion of isolated forest areas by infill
  development
• Rural - urbanizing areas (Upstream region -
  newly incorporated)
• Dispersed conversion
• Aggregation
• Edge expansion

9
Assessing land-hydrologic changes in Cedar River
tributaries

• Develop land covers for evaluating landscape
  changes
• Changes in developed areas
• Analyze the extent of impervious (NDVI)
• Quantify changes in developed land cover between
  1991 and 1998 that could influence the
  hydrological processes of watersheds, riparian
  and aquatic habitats
• Use coverages in a fine-resolution spatial
  hydrological model adapted from Wigmosta, et al.
  (1994) to assess the impact of land-use change on
  stream discharge for 1991, 1998, and historical
  landscapes
• Use above information and DHSVM to simulate
  flooding of lowland areas within different
  tributary watersheds.
• Compare simulations for 1991, 1998, and
  historical landscapes

10
Maplewood Creek Hydrologic Changes

• Impact of landcover changes on discharge was
  evident in comparisons of changes in the percent
  differences (? ) in annual peak flow for various
  recurrence intervals (years).
• Years Hist. 1991 1998 91-98 Hist-91 Hist-98
• ----------Discharge (cfs)-------------- --------
  -------- ( ?)------------------
• 20 46 70 75 7 52 63
• 60 74 108 120 11 46 62
• 100 78 117 130 11 50 67
• Between 1991 and 1998, changes in annual peak
  flow were 7, 11, and 11, at the 20, 60 and 100
  year recurrence intervals, respectively.
• Much greater differences in discharge rates were
  evident between historical conditions and the
  developed 1998 landscape. The annual peak flow
  ranged between 62 and 67 for the same return
  intervals.
• Similar changes were evident for differences
  between historical and 1991 conditions (46 to
  52).

11
(No Transcript)
12
PART II River Restoration and Protection
Analysis

• Spatial distributions of ecologically functional
  and human-influence zones along rivers, Timm et
  al. (In review)
• How are ecologically functional habitats and
  anthropogenically altered areas influencing
  riverine habitats within the floodplain?
• Can co-occurring, ecologically functional and
  anthro-pogenic landcovers be used to identify
  opportunities for habitat restoration within the
  floodplain?
• Land-use practices and erosion risk potential,
  Wissmar et al. (In prep.)
• Risks created by human land and water use
  practices within naturally unstable areas lead to
  cumulative impacts on ecosystem functions
• Risk assessments facilitate planning and
  implementation

13
Lower Cedar Basin Restoration Potential
-4 -3 -2 -1 0 1 2 3 4
14
(No Transcript)
15
(No Transcript)
16
Protection of Riparian Habitats in Erosion-prone
Landscapes

• Objectives
• Determine erosion risk scores that indicate the
  absence and presence of different factors
  contributing to erosion hazards
• Assess the spatial distribution of erosion risks
  in watersheds
• Identify variable riparian buffer widths assigned
  to erosion risk scores

17
FACTORS PRESENT
FACTORS ABSENT
1
2
Rain on Snow elevations

Unstable soils

Immature forest stands

Roaded areas

Critical slopes
EROSION RISK SCORE
18
Riparian Buffers
19
Part III Salmon Habitat Selection

• Habitat Selection by Salmonids, Hall et al.
  (2000, 2002)
• What habitat factors do spawning salmon prefer?
• What habitat factors do juvenile salmon prefer?
• Implications for Habitat Restoration
• What is the predicted fish response to
  restoration/ mitigation prescriptions?
• Can we incorporate this into restoration plans?

20
Spawning Objectives

• Identify important habitat variables
• Measure habitat selection
• Explore role of density on habitat selection

21
Adult fish picture
22
Habitat Electivity Indices (D)D r-p/(rp) 2rp
23
Spawning Conclusions
W79 Wetland 79, CAV Cavanaugh Pond
24
Juvenile Sockeye SalmonObjectives

• Determine selected ranges of habitat factors
  considering day-night and seasonal differences
• Examine how fish size and fish density affects
  habitat use
• Investigate overlap with potential predators
• Identify extent of use in the newly constructed
  habitat at Wetland 79

25
Juvenile fish picture
26
Juvenile Conclusions

• Juvenile habitat use appeared to be driven by the
  threat of predation.
• -moved to deeper areas to avoid predation from
  birds
• -formed larger schools as protection from
  aquatic predators
• -majority of fish used cover
• -preferred complex woody debris
• Fish appeared to avoid warmer temperatures and
  low dissolved oxygen levels, however, it remains
  uncertain how these factors may limit habitat
  use.
• Sockeye did not select for other habitat factors.

27
Part IV Disturbance, Habitat Protection and
Restoration

• Disturbance Regimes, Habitat Interactions and
  Restoration Across Riverine Landscapes, Timm,
  Ph.D. Dissertation (In prep)
• Evaluating how ecologically functional and
  anthropogencially developed areas influence
  riverine/ floodplain habitats
• Spatially modeling interactions between channel
  hydraulics and local floodplain hydrology
• Testing procedures to identify opportunities for
  habitat restoration within the basin

28
(No Transcript)
29
(No Transcript)
30
(No Transcript)
31
(No Transcript)
32
(No Transcript)
33
Acknowledgements

• U.S. EPA Grant R827149-01-0
• PRISM
• King County
• City of Renton
• City of Seattle
• U.S. Forest Service
• U.S. Army Corps of Engineers
• Washington Dept. of Fish Wildlife