Applying Reconciliation Ecology Concepts To Salmonid Habitat ...
Applying Reconciliation Ecology Concepts To Salmonid Habitat Restoration And Enhancement
Mike Burke, Nick Nelson, Greg Koonce, Manny DaCosta and Marty Melchior
Motivations
• Share experiences in planning and implementing salmonid habitat enhancement in highly altered, yet natural settings that are critically important for conservation of salmonids.
• Use a pair of contemporary ecological paradigms to frame the associated nuances and complexities.
Outline
• Definitions • Context • Introduce Case Study • Design Application • Results – Habitat and Utilization
Definitions Novel Ecosystem
(Seastedt et al. 2008):
• Interactions between altered river systems and alien species are resulting in unprecedented combinations of species in habitat quite different from undisturbed habitat • ‘In managing novel ecosystems, the point is to not think outside the box, but to recognize that the box itself has shifted.’
Reconciliation Ecology
(Rosenzweig 2003):
• Practical approach to living with the new reality of these ecosystems for which recovery may be unattainable or even inadvisable • Manage these systems to provide desirable attributes, in particular to conserve biodiversity and critical species
Application Context
Focused on Physical Habitat Improvement: • Interaction of the altered physical processes can be similarly unprecedented • Nearly all habitat restoration effort is a direct application of reconciliation ecology • WRT to stream processes and how they create, destroy and maintain habitat, it is essentially important to not only understand that the ‘box’ has moved, but also: • Is the box still moving? • In what direction and how fast? • What is left in the box to work with?
Case Study
Dry Creek: • 230 mi2 watershed • 150 years of impacts lead stream far from its state at time of European contact • Chinook and coho salmon, steelhead trout • Critical resource for regional recovery of coho and steelhead • Abundant cold water in late summer over gravel substrate, rare for region (artifact of regulation) • Microcosm of overlapping alterations within a 14-mile reach of stream downstream of dam
Legacy of Alteration
• 1850 - 1900: Deforestation and agricultural conversion • 1910 – 1975: Instream gravel mining
• Led to systemic incision (20 -25 ), slowed by end of period • Disconnection of lateral habitats and floodplain
Legacy of Alteration
• 1980 - present: dam construction and regulation
• Curtails sediment continuity and floods, elevates base flow • Veg encroachment, sequester alluvium, channelization , • Efficient at transporting available gravels
Current Function (what s left and where s it going) • Laterally and vertically stable, minimal disturbance
• limited lateral habitat creation/revitalization – limited refugia • limited recruitment of substrate and LWD •
it s stuck – not empowered or able to create new habitat
Current Function (what s left and where s it going) • Highly efficient at transporting available sediment with regulated hydrology • limited roughness, short substrate residence time
• Deficit of riffle habitat • Poor quality pools: swift water, limited complexity and cover
Prescriptions
• Disturbance!: § thin overbank vegetation to enable recruitment of legacy substrate and promote geomorphic change § energy dissipation
Prescriptions
• Sediment Augmentation: §
seed riffles with sediment caliber that is better fit for regulated hydrology,
§ Energy breaks improve residence time for substrate
Prescriptions
• Supplement LWD: § Provide cover and complexity, § Foster habitat development – scour and deposition § Enhance substrate residence time
Prescriptions • Rejuvenate lateral habitats and floodplains: § Backwaters, side channels, alcoves § Adjust to present base level and hydrology
Feedback (so far) • Intensive monitoring of fish utilization
Feedback (so far) • Intensive monitoring of fish utilization
Feedback (so far) • Intensive monitoring of fish utilization
Summary Points § Nearly all river systems are moderately to substantially altered from their predisturbance state, yet are essential for conservation of critical species. § The paradigms of the novel ecosystem and reconciliation ecology are useful for characterizing the realities of physical habitat enhancement planning and implementation. § In order to successfully achieve habitat enhancement objectives, it is necessary to reconcile the history of alteration, current physical function and future trajectory. § Often, intervention is required to nudge the physical system towards a trajectory that can sustain and replenish the habitat that is enhanced.
Applying Reconciliation Ecology Concepts To Salmonid Habitat Restoration And Enhancement Citations § Moyle, P.B., 2013. Novel Aquatic Ecosystems: The New Reality for Streams in California and Other Mediterranean Climate Regions. River Res. Applic., DOI 10.1002/rra.2709. § Rosenzweig, M.L. 2003. Win-win Ecology: How the Earth’s Species Can Survive in the Midst of Human Enterprise. Oxford University Press. Oxford. § Seastedt, T.R, Hobbs, R.J, Suding, K.N. 2008. Management of Novel Ecosystems: Are Novel Approaches Required? Frontiers in Ecology and Environment 6: 547-553
Acknowledgements § Sonoma County Water Agency, NMFS, CDFW
Mike Burke, Nick Nelson, Greg Koonce, Manny DaCosta and Marty Melchior
Motivations
• Share experiences in planning and implementing salmonid habitat enhancement in highly altered, yet natural settings that are critically important for conservation of salmonids.
• Use a pair of contemporary ecological paradigms to frame the associated nuances and complexities.
Outline
• Definitions • Context • Introduce Case Study • Design Application • Results – Habitat and Utilization
Definitions Novel Ecosystem
(Seastedt et al. 2008):
• Interactions between altered river systems and alien species are resulting in unprecedented combinations of species in habitat quite different from undisturbed habitat • ‘In managing novel ecosystems, the point is to not think outside the box, but to recognize that the box itself has shifted.’
Reconciliation Ecology
(Rosenzweig 2003):
• Practical approach to living with the new reality of these ecosystems for which recovery may be unattainable or even inadvisable • Manage these systems to provide desirable attributes, in particular to conserve biodiversity and critical species
Application Context
Focused on Physical Habitat Improvement: • Interaction of the altered physical processes can be similarly unprecedented • Nearly all habitat restoration effort is a direct application of reconciliation ecology • WRT to stream processes and how they create, destroy and maintain habitat, it is essentially important to not only understand that the ‘box’ has moved, but also: • Is the box still moving? • In what direction and how fast? • What is left in the box to work with?
Case Study
Dry Creek: • 230 mi2 watershed • 150 years of impacts lead stream far from its state at time of European contact • Chinook and coho salmon, steelhead trout • Critical resource for regional recovery of coho and steelhead • Abundant cold water in late summer over gravel substrate, rare for region (artifact of regulation) • Microcosm of overlapping alterations within a 14-mile reach of stream downstream of dam
Legacy of Alteration
• 1850 - 1900: Deforestation and agricultural conversion • 1910 – 1975: Instream gravel mining
• Led to systemic incision (20 -25 ), slowed by end of period • Disconnection of lateral habitats and floodplain
Legacy of Alteration
• 1980 - present: dam construction and regulation
• Curtails sediment continuity and floods, elevates base flow • Veg encroachment, sequester alluvium, channelization , • Efficient at transporting available gravels
Current Function (what s left and where s it going) • Laterally and vertically stable, minimal disturbance
• limited lateral habitat creation/revitalization – limited refugia • limited recruitment of substrate and LWD •
it s stuck – not empowered or able to create new habitat
Current Function (what s left and where s it going) • Highly efficient at transporting available sediment with regulated hydrology • limited roughness, short substrate residence time
• Deficit of riffle habitat • Poor quality pools: swift water, limited complexity and cover
Prescriptions
• Disturbance!: § thin overbank vegetation to enable recruitment of legacy substrate and promote geomorphic change § energy dissipation
Prescriptions
• Sediment Augmentation: §
seed riffles with sediment caliber that is better fit for regulated hydrology,
§ Energy breaks improve residence time for substrate
Prescriptions
• Supplement LWD: § Provide cover and complexity, § Foster habitat development – scour and deposition § Enhance substrate residence time
Prescriptions • Rejuvenate lateral habitats and floodplains: § Backwaters, side channels, alcoves § Adjust to present base level and hydrology
Feedback (so far) • Intensive monitoring of fish utilization
Feedback (so far) • Intensive monitoring of fish utilization
Feedback (so far) • Intensive monitoring of fish utilization
Summary Points § Nearly all river systems are moderately to substantially altered from their predisturbance state, yet are essential for conservation of critical species. § The paradigms of the novel ecosystem and reconciliation ecology are useful for characterizing the realities of physical habitat enhancement planning and implementation. § In order to successfully achieve habitat enhancement objectives, it is necessary to reconcile the history of alteration, current physical function and future trajectory. § Often, intervention is required to nudge the physical system towards a trajectory that can sustain and replenish the habitat that is enhanced.
Applying Reconciliation Ecology Concepts To Salmonid Habitat Restoration And Enhancement Citations § Moyle, P.B., 2013. Novel Aquatic Ecosystems: The New Reality for Streams in California and Other Mediterranean Climate Regions. River Res. Applic., DOI 10.1002/rra.2709. § Rosenzweig, M.L. 2003. Win-win Ecology: How the Earth’s Species Can Survive in the Midst of Human Enterprise. Oxford University Press. Oxford. § Seastedt, T.R, Hobbs, R.J, Suding, K.N. 2008. Management of Novel Ecosystems: Are Novel Approaches Required? Frontiers in Ecology and Environment 6: 547-553
Acknowledgements § Sonoma County Water Agency, NMFS, CDFW
