Woodland Creation & Ecological Networks (WrEN project)

Transcription

1 Woodland Creation & Ecological Networks (WrEN project)

2 Acknowledgements Collaborators/co-authors Mark Ferryman Elisa Fuentes-Montemayor Lauren Fuller Jonathan Humphrey Ed Lewis Bill Kunin Nick Macgregor Suzie May-Graham Kevin Watts Marike Whyte Robbie Whytock Field assistance and advice: Roy Allen, Thomas Armitage, Katy Baird, Katja Bitenc, Lorna Blackmore, Stephen Brennan, Pete Carey, Ruth Coxon, Paul French, Lloyd Garvey, Natasha Hambly, Ian Hayward, Joe Hope, Jamie Irvine, Holly Langridge, Zeltia Lopez, Rory Whytock, Scott Wilson, + many staff at Forestry Commission, Forest Research, Natural England Funders & assistance: Land owners for access

3 Habitat loss & fragmentation

4 Landscape-scale conservation

5 Ecological restoration following habitat loss Building & enhancing ecological networks conservation policy A suite of core habitat areas connected by buffer zones, corridors and smaller stepping stones - movement of species / propagules Sound scientific principles but limited empirical evidence for prioritisation Ecological networks Making Space for Nature Report 2010

6 species species Responses to fragmentation vs. restoration extinction debt colonisation credit time time

7 No. replicates Experiments Experimentation in landscape-scale in landscape-scale conservation conservation Experimentation is fundamental to inform conservation, but rare and challenging approach at larger scales Challenge 1: spatial scale Experimental control/replication vs. ecological realism Area of patch (ha) Haddad 2012

8 Experiments Challenges for in landscape-scale landscape-scale conservation conservation Experimentation is fundamental to inform conservation, but rare and challenging approach at larger scales Challenge 1: spatial scale Experimental control/replication vs. ecological realism Challenge 2: temporal scale Slow habitat development Time lag in biodiversity response Natural experiments: extend spatial & temporal scale of manipulative experiments

9 The role for natural experiments Rigorous site selection in natural experiments can maintain ecological realism & control Especially relevant at landscape scales Bigger, better, more, joined - how to prioritise? Ecological networks Making Space for Nature Report 2010

10 The role for natural experiments Landscape-scale conservation projects currently underway to implement ecological networks (e.g. NIAs in England) May be many years until biodiversity benefits of current actions are realized But we could go back in time and assess the merits of past actions on current biodiversity Nature Improvement Areas

11 The WrEN project a unique opportunity Long-term, large-scale woodland creation Long-term, large-scale mapping (to 1850) By Defra, OGL,

12 The WrEN project 1. Focus on habitat creation (rather than fragmentation) 2. Include spatially realistic scales 3. Cover long time scales 4. Consider a range of explanatory site/patch and landscape-level variables 5. Study the response of a wide range of taxa

13 The WrEN project A natural experiment approach to assess the effects of past landscape change on current biodiversity to inform future conservation actions. Historic maps used to id woodland patches created in the past 150 years. Woodlands systematically selected to reflect variation in key local and landscape-level attributes. Woodlands surveyed for a range of woodland-dependent species Time

14 WrEN secondary woodland sites Two study landscapes: Scotland (~ 7335 km 2 ) England (~8,570 km 2 ) Lowland agricultural landscapes 2 o woodlands yrs Controlling soil, topography & climate o woodlands 26 ancient woodlands

15 Site selection Semi-automated site selection protocol Digital spatial datasets & historic maps to identify secondary woodland patches of different character/configuration: Bigger (size) Better (ecological continuity) More (surrounding woodland) Joined (connectivity with woodland)

16 Site selection Bigger Better (age) More Joined

17 Site & landscape-scale attributes understorey cover canopy cover tree diameter area age surrounding habitat spatial isolation surrounding matrix

18 Taxa selection Woodland-dependent species that vary in life-history traits, likely responses to woodland structure, spatial configuration and landscape context: Lower plants (lichens and bryophytes) Vascular plants Invertebrates (ground-dwelling & flying) Small mammals Bats Birds Now at 1145 species

19 Example results John Altringham David Nicholls Paul Ruddoch

20 species mobility Responses of bats to habitat creation high Myotis spp. + Pipistrellus pipistrellus + Pipistrellus pygmaeus low Plecotus auritus Local Landscape Fuentes-Montemayor et al. (2016) Ecological Applications

21 species mobility Responses of bats to habitat creation high Woodland age: Myotis spp. Tree size, variation in size Tree density, understorey (species-specific) High mobility: woodland amount important + Pipistrellus pipistrellus Low / intermediate mobility: woodland configuration important + Pipistrellus pygmaeus low Plecotus auritus Local + Landscape Landscape particularly important in more homogeneous landscapes (England)

22 Analytical approach: Structural Equation Models Patch area Landscape-scale Patch shape Local-scale Size Surrounding habitat Amount of woodland (any, broadleaved, ancient) Patch age Tree density Tree sp. richness Woodland inter-connectivity (any, broadleaved, ancient) Tree size (mean) Tree size (SD) Quality Connectivity Understorey % Grazing? Biodiversity Land cover type / Matrix permeability

23 Analytical approach: Structural Equation Models Patch area Patch shape Size Surrounding habitat Patch age Indirect effects of age Amount of woodland (any, broadleaved, ancient) Tree density Tree sp. richness Woodland inter-connectivity (any, broadleaved, ancient) Tree size (mean) Tree size (SD) Quality Connectivity Understorey % Grazing? Biodiversity Land cover type / Matrix permeability

24 Responses of bird communities to habitat creation Functional groups described using feeding, breeding, resting habitats (French & Picozzi 2002) 7791 records of 46 species (5 26 per site) Those in woodland related groups most commonly recorded Whytock et al. (2017) Conservation Biology

25 Structural Equation Models: birds Patch area Patch shape Patch age Indirect effects of age Size Surrounding habitat Amount of woodland (any, broadleaved, ancient) Tree density Tree sp. richness Woodland inter-connectivity (broadleaved) Tree size (mean) Tree size (SD) Quality Connectivity Understorey % Grazing? Bird abundance & species rich. Land cover type / Matrix permeability Size is x2 as important

26 Hoverflies in secondary woodlands c hoverflies / 65 species 40% of species were woodland associated but only 10% individuals Paul Ruddoch Mick E Talbot Fuller et al. (2017) Journal of Applied Ecology

27 Structural Equation Models: hoverflies Patch area Patch shape Patch age Indirect effects of age Size Surrounding habitat Amount of woodland (any, broadleaved, ancient) Tree density Tree sp. richness Woodland inter-connectivity (any, broadleaved, ancient) Tree size (mean) Tree size (SD) Quality Connectivity Understorey % Grazing? hoverfly abundance & species rich. Land cover type / Matrix permeability Focus on woodland quality

28 Implications for woodland creation & management so far. Species mobility important in determining relative importance of local vs. landscape-level attributes For lower mobility sp quality and configuration of habitat is important Response of generalists vs specialists For birds, woodland size > 2x as important as other metrics considered

29 The WrEN project what s next? Synthesis of taxa-specific results WrEN sites in context: comparison with ancient woodlands Guidance for policy & practitioners Below-ground biodiversity; effects on soil and carbon stocks; functional diversity / ecosystem functioning

30 For more information: Web: Two PhDs currently being advertised Seeing the woods for the trees: do woodland networks benefit biodiversity? How does woodland creation influence below-ground biodiversity, and soil and ecosystem functions? Full details on findaphd.com