Novel Ecosystems: The Changing Landscape of Ecological Restoration

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1 Novel Ecosystems: The Changing Landscape of Ecological Restoration Valentin Schaefer, Ph.D., R.P.Bio. Restoration of Natural Systems Program University of Victoria

2 Definition Ecosystems that differ in composition and/or function from present and past systems Hobbs, Higgs, Harris 2009 Arise through human action, climate change, and invasive species Hobbs et al 2006 Emerging, no analog University Centre pond with red-eared sliders, duckweed and yellow flag -headwaters of Bowker Creek, Victoria

3 Ecological Restoration is the process of assisting the recovery of an ecosystem that has been degraded, damaged or destroyed. Traditionally meant restoring to a historic reference ecosystem

4 Restoration Target Challenges with Historic Reference Ecosystem Common Earthworm Introduced into NA 1700s - Transformer species Pristine Wilderness seen by European settlers actually Second growth forest after corn fields abandoned Thomas Mann 1491

5 Novel Ecosystem Approach Focus of goals is on key species of conservation interest Involves a constantly adaptive approach Invasive species may be controlled with no realistic option of eliminating them

6 Novel ecosystems arise either from the degradation and invasion of wild or natural/seminatural systems or from the abandonment of intensively managed systems. Hobbs et al. 2006

7 Why Now Why Ecological Restoration Invasive species Climate change Urban ecosystems Restoration targets Limited resources Great Blue Heron heronry Stanley Park, Vancouver

8 Invasive species Smallest satellite populations first

9 Examples of Priority Sites Environmentally sensitive areas Pose danger to human health High community interest High dispersal capacity such as upstream Highly visible sites Economic impacts Knotweed sp. Carpet burweed exclosure

10 Novel Ecosystem A Different Box From Seastedt, Hobbs and Suding 2011 Intervention Ecology vs Ecological Restoration

11 Adapting to Climate Predicting range changes

12 Smaller Changes - Hybrid Systems Retain some original characteristics plus acquire novel elements Wattling with Pacific willow to stabilize banks of Bowker Creek; invasive yellow willow cut and left in place

13 Larger Changes Novel Systems Different species Different interactions Different functions Heavy infestation of English ivy in Mystic Vale: climbing ivy will be cut from trees, ivy on ground will be left in place except for sensitive areas

14 Novel Elements of Existing Ecosystems Prevalence of a single species not present before Dependence of native animals on non-native plants Dependence of native species at risk on novel ecosystems Naked broomrape on Non-native sedum Urban Forest Cultivars of Non-native Species Urban forest with atlas cedars cultivar to grow tall and narrow - Seattle

15 Implications of Novel Ecosystems Restoration Targets Significant shift from the traditional placebased focus on existing or historical assemblages as reference sites Ecosystems Are they persistent? Do they have value? Bowker Creek 80% in storm drains Bowker Creek valued for passive recreation

16 Novelty Value: When and How to Intervene May be better to allocate resources to ecosystems in a hybrid state Douglas Creek regularly devastated by heavy storm drain flows difficult to re-establish salmon spawning beds

17 Criteria for a Novel Ecosystem as a Suitable Restoration Target Is the capable of maturing Is it on a stable trajectory Is it resistant and resilient Is it providing ecosystem goods and services Is it providing opportunities for individual or community engagement Is a transformer species involved Bowker Creek valued for passive recreation - 80% in Storm drains

18 Barriers to Implementing Novel Ecosystems as New Management Technique Convincing public that not giving up Setting management objectives e.g. if Himalayan blackberry is target, is maximum coverage 30% Himalayan blackberry riparian zone

19 What Are Novel Ecosystems Termed novel, emerging or no-analog Considered primarily in relation to native species or climate change Ignored in past in ecological theory and management but now a growing part of the world Many thresholds in play, both ecological and social, preventing a system from returning to its natural state

20 What It Is not Not against traditional conservation approaches Still recognize value of protecting places and ecosystems with original biota and historical value Not suggesting traditional restoration approaches to restore historical ecosystem structure and function are no longer relevant Not against removing invasive species Not an argument for encouraging novelty

21 What It Is For Being open to new goals and approaches Being open to traditional approaches applied in new ways Helping to shape the development of a management framework to address rapidly changing ecosystems

22 Examples of Novel Ecosystems Shale dumps in Scotland Everglades in Florida Many island systems as in the Seychelles and Puerto Rico for plants and Christmas Island for animals