The cumulative impact of wind farms on bats: a regional landscape approach ROSCIONI F., RUSSO D., DI FEBBRARO M., LOY A.

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1 The cumulative impact of wind farms on bats: a regional landscape approach ROSCIONI F., RUSSO D., DI FEBBRARO M., LOY A. CWE2013 Conference on Wind power and Environmental impacts Stocholm February 2013

2 IMPACTS OF WIND FARMS ON BAT POPULATIONS COLLISIONS INTERFERENCES WITH COMMUTING AND MIGRATION ROUTES FORAGING HABITAT LOSS OR ALTERATION INTERFERENCE WITH ROOSTS

3 CUMULATIVE IMPACT ALLOWS TO DETERMINE LARGE SCALE IMPACTS THAT ARE NOT DETECTABLE ON A LOCAL SCALE: foraging habitat loss, cumulative collision risk, connectivity alteration etc. To date,one case-study,for Portugal (Santos et al. 2013) Our model: landscape pattern alterations which potentially represents an important component to cumulative impact.

4 OBJECTIVES MODELLING FORAGING HABITAT for two bat species on a regional scale Regional RISK MAPS by overlaying foraging habitat maps with existing and planned wind farms locations Assessment of CHANGES in the spatial pattern of foraging habitat determined by existing and planned wind turbines Identification of HIGH VULNERABLE AREAS where wind farm construction would be especially harmful to bats and should be avoided.

5 STUDY AREA MOLISE REGION 4.437,58 km² 39 wind farms (28 operating and 11 planned), for a total of 543 wind turbines

6 WHICH SPECIES? Nyctalus leisleri Pipistrellus pipistrellus WHY? Endangered Flies at high altitudes Vulnerable to wind farms impact, especially in southern Europe Migrant (Rodrigues et al., 2008, Telleria, 2009).

7 Environmental data Environmental variable matching ecological requirement of the species Altitude (0-2000) Vegetation type (forests, complex agriculture) Presence of freshwater bodies (important for feeding and migration) Map feature PROXI Digital Terrain Model (30 m cell grid) Corine Land Cover map at IV and V level of resolution -> focal statistics Hydrographic map (30 m cell grid) -> euclidean distance MAXIMUM ENTROPY (MAXENT 3.3.3k) Presence data 38 presence data of N. leisleri and 56 presence data of P. pipistrellus in Molise

8 CLC categories used in the inferential models focal statistics used to convert CLC categorical into continous

9 Risk map N. leisleri P. pipistrellus COMBINED MODEL OF BOTH SPECIES Treshold of probability of presence : 10th percentile GEOGRAFICAL LOCATION OF EXISTING AND PLANNED WIND FARMS BUFFERED 150m (Rodrigues et al. 2008, Arnett et al. 2008) INCLUDED IN COMBINED MODEL

10 Class area (CA) Number of Patches (NP) Mean Patch Size (AREA_MN) the extension of each class in hectares Largest Patch Index (LPI) landscape percentage occupied by the greatest patch of the interest class Landscape Pattern analysis FRAGSTAT 3.3 Version (McGarigal & Marks, 1995) Three classes of suitable feeding areas: suitable for P. pipistrellus, suitable for N. leisleri, and suitable for both species. Run considering and omitting wind farms Fragmentation Indices the number of patches present in the class of interest Area Weighted Mean Shape Index (SHAPE_AMN) quantifying the landscape configuration in terms of complexity of the patches that constitute it the mean size of patches in the class of interest Aggregation Index(AI) describes the adjacencies of habitat cells

11 FORAGING HABITAT SUITABILITY MAP for N. leisleri 1 = SUITABLE 0 = NO 42% suitable Maximum probability of presence at 0.86 (AUC = 0.835) AUC = 0.83

12 FORAGING HABITAT SUITABILITY MAP for P. pipistrellus 1 = SUITABLE 0 = NO 50% suitable Maximum probability of presence at 0.86 (AUC = 0.835) AUC = 0.80

13 BINARY MAPS 50% suitable 42% suitable 41% suitable

14 RISK MAP for N. leisleri and P. pipistrellus 41% SUITABLE FOR BOTH SPECIES 66.67% of existing turbines on suitable areas-699ha subtracted HABITAT LOSS EXISTING W. F.: 0.65% for N. leisleri 0.70% for P. pipistrellus 0.69% for both species 51.45% of planned turbines on suitable areas- 1092ha subtracted HABITAT LOSS EXISTING + PLANNED W.F.: 1.00% for N.leisleri, 1.00% for P. pipistrellus and 1.06% for both species

15 Landscape Pattern analysis FRAGSTAT 3.3 Version (McGarigal & Marks, 1995) Indices Species no wind farms % variation % variation existing existing wind + farms planned wind farms CA (ha) P. pipistrellus 22, CA (ha) N. leisleri 18, CA (ha) Both species 17, NP P. pipistrellus NP N. leisleri NP Both LPI (%) P. pipistrellus LPI (%) N. leisleri LPI (%) Both species Area MN (ha) P. pipistrellus 2, Area MN (ha) N. leisleri 1, Area MN (ha) Both species 1, Shape AMN P. pipistrellus Shape AMN N. leisleri Shape AMN Both species AI (%) P. pipistrellus AI (%) N. leisleri AI (%) Both species

16 Overlap with forest edges 13% of existing turbines fell within ha of forest edges 21% of the total (planned + existing) turbines fell within ha

17 REMARKS Changes in patches of limited size, leading to the formation of even smaller, discontinuous and isolated patches (increase in the number of patches, variation in LPI and AI indices). Any macro fragmentation effect habitat incision, dissection and perforation effects, all typical of an initial phase of habitat fragmentation (Forman 1995). Increase in the complexity of habitat patch edges (variation of Shape Index). Many bat species forage along edges (Limpens and Kapteyn 1991; Grindal and Brigham 1999; Morris et al. 2010; Ethier and Fahrig 2011; Müller et al. 2012).

18 IMPLICATION FOR CONSERVATION The western part of the Molise region is the most suitable for the presence of N. leisleri and P. pipistrellus this area has to be considered critical in wind farm planning and in conservation strategies Habitat loss: 1% on a regional scale More tha 50% of turbines fell in suitable areas ECOLOGICAL TRAP! (Wickramasinghe et al. 2003; Ahlén et al. 2007, 2009; Horn et al. 2008; Rydell et al. 2010) Planned turbines felling within forest edges of suitable areas should be avoided (Rodrigues et al.2008)

19 Roscioni F., Russo D., Di Febbraro M., Frate L., Carranza M.L., Loy A. Regionalscale modelling of the cumulative impact of wind farms on bats. WORK IN PROGRESS In collaboration with dr Hugo Rebelo CIBIO/UP wind facilities in suitable foraging areas BARRIER EFFECT increasing the collision risk for migratory species (e.g. N. leisleri) (Rodrigues et al. 2008; Weller & Baldwin, 2011) existing wind farms planned wind farms N. Leisleri connectivity map Models for all species impacted by wind farms in Molise Region improved by adding variables proxi of linear features and wind exposure. Connectivity analyses: species specific and combined

20 ACKNOWLEDGEMENTS Molise Region for providing the maps of wind turbine locations Inergia SpA which in 2010 partly funded the research THANK YOU!