Bat fauna monitoring before and during operation phase of the wind farm Danilo in Croatia Dina Rnjak, mag. oecol. et prot. nat.

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1 Bat fauna monitoring before and during operation phase of the wind farm Danilo in Croatia Dina Rnjak, mag. oecol. et prot. nat. Vida Zrnčid, mag. oecol. et prot. nat. Goran Rnjak, bacc. ing. aedif. Nikola Hanžek, mag. oecol. et prot. nat. Dr. sc. Marin Grgurev, Gekom d.o.o.

2 Geonatura Ltd. Consultancy in Nature Protection among others, a team specialized in bat fauna research - impact assessments, pre- and post-construction monitoring, mitigation measures design for bats From 2013: - baseline surveys for 6 WF in Croatia and 1 in Bosnia and Herzegovina - one-year post-construction monitoring at 2 WF in Croatia

3 Survey design and methodology national guidelines (Ministry of Environmental Protection, Physical Planning and Construction and APO Ltd. 2010) taking also into consideration international guidelines of UNEP/EUROBATS depending on a project, it can include periodic and continuous bat detector monitoring investigation of potential and monitoring of important roost sites mist-netting searching for bat fatalities

4 WF Danilo RP Global Danilo Ltd. Šibenik-Knin County in Croatia locations Bubrig (10 WT) and Velika Glava (9 WT) Mediterranean karst region dry and rocky pastures which have mostly turned into shrubs Total installed capacity: 43.7 MW Turbine type: Enercon E-82 Number of WT: 19 Tower height: 78 m Rotor diameter: 82 m

5 Given the absence of a one-year bat fauna research during the environmental impact assessment (EIA) (there was no legal obligation for this type of research until 2009), the first year of monitoring was carried out through a detailed one-year preliminary study of bat populations in the wider area around the planned construction site

6 One-year bat monitoring before operation phase ACTIVITY Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Collection and analysis of existing data - spatial data - literature data - survey design Field surveys Periodic bat detector monitoring Investigation of potential and important roost sites Mist netting Processing and analysis of collected data

7 Periodic bat detector monitoring to determine present bat species and their activity main transects through WT locations + control transects in the lowland which included other types of habitats when highest activity can be expected (1-2 h after Sunset) determined whether bats were passing through or foraging temperature, humidity, wind speed were measured at the beginning and end of each survey

8 Investigation of potential and monitoring of important roost sites caves, tunnels, buildings etc. in the 5 km buffer area locations, type of roost, species abundance and composition microclimatic conditions measured inside and outside potential bat roosts

9 Mist netting in order to identify present species, as well as their sex, age and reproductive status

10 Processing and analysis of collected data echolocation/sound analysis GIS analysis bat activity analysis - spatial and temporal distribution Site-specific assessment possible critical periods with risk of bat fatalities species at highest risk for collision and/or barotrauma possible need for mitigation measures

11 Results 13 bat species, along with phonic species groups June gravid females of P. kuhlii and Pl. macrobullaris by mist netting P. kuhlii and H. savii - most frequently use the Project area and potentially most vulnerable low bat activity level during early spring, mid-summer and late autumn high bat activity during seasonal migrations May - 74,9 contacts/h Velika Glava - 111,1 contacts/h September - 44,2 contacts/h

12 24 underground sites surveyed (the deepest 104 m and the longest 117 m) - in 15 no bat presence was recorded, up to 10 bats were recorded in 6 caves EUROBATS important underground sites (Natura 2000 sites) monitored regularly: 1. Škarin Samograd - Mn. schreibersii, M. capaccinii, M. myotis/blythii, R. euryale 2. Dobra voda - M. emarginatus, R. ferrumequinum 3. Stražbenica - M. emarginatus, R. euryale, R. ferrumequinum

13 One-year bat monitoring in operation phase ACTIVITY Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Field surveys Searching for bat fatalities Periodic bat detector monitoring Continuous bat detector monitoring Monitoring of important roost sites Processing and analysis of collected data

14 Searching for bat fatalities within 70 m radius of WTs approx. 45 minutes/man/wt with max. time intervals of 15 days (8-12) found bat carcass: o photo documentation o position (coordinates, terrain visibility, closest WT, distance from the WT) o state of the carcass (fresh, a few days old etc.), type of injury o taxonomic affiliation, sex and age (if possible)

15 taking into account ground cover and terrain morphology visibility classes were determined: 1. Areas of high visibility - plateaus, slopes, roads 2. Areas of low visibility - shrubs and high grass - not searched given the size of bat carcasses and quick changes in appearance (from fresh carcass to skeleton) WT II-3: Percentage of area searched: 25,1 % Percentage of weighted area searched (expected density of bat carcasses on the ground): 52,4 %

16 Testing the carcass removal rate setting up 25 dead mice on search plots in May and September 2014 monitoring the speed of their disappearance to estimate removal rate and then annual bat mortality calculated average time for carcass persistence: 8,6 days

17 Estimation od annual bat mortality estimation of the real number of bat fatalities at the wind farm carcass package" Korner-Nievergelt et al (based on Huso 2010 and Etterson 2013) the number of found carcasses/injured individuals time intervals between two searches carcass removal rate searcher efficiency (100%) percentage of area searched in the 70 m radius variable probability of finding carcasses regarding the distance from WT

18 Monitoring of important roost sites EUROBATS important underground sites (within Natura 2000 sites) were monitored during maternity season: 1. Škarin Samograd cave 2. Dobra voda 3. Stražbenica cave Periodic bat detector monitoring main transects defined during the baseline survey (February - November) when highest activity can be expected microclimate conditions measured at the beginning and end of each survey

19 Continuous bat detector monitoring set up on a weather mast through full cycle of bat activity temporal distribution, bat activity index in correlation to weather conditions (air temperature, wind speed)

20 Bat activity analysis BatSound, Sonobat, BatExplorer and Kaleidoscope software bat species activity index (corrected with species detectability), activity type, spatial and temporal distribution correlation to microclimatic conditions (based on the data on wind speed and temperature from a weather mast given by RP Global Ltd.)

21 Results # Bat species IUCN 1 Mediterr. IUCN 1 HR HD 2 92/43 EEC Status Croatia Collision risk Percentage of bat fatalities (min-max) 6 1 Hypsugo savii LC - IV Very common x 29,4-30,9 % 2 Miniopterus schreibersii NT EN II, IV Common x - 3 Myotis bechsteinii NT VU II, IV Common - 4 Myotis capaccinii VU EN II, IV Common - 5 Myotis emarginatus LC NT II, IV Very common - 6 Myotis myotis LC NT II,IV Common - 7 Myotis blythii NT - II,IV Very common - 8 Nyctalus leisleri LC NT IV Common x 5,9-7,4 % 9 Nyctalus noctula LC - IV Very common x - 10 Pipistrellus kuhlii LC - IV Very common x 35,3-45,6 % 11 Pipistrellus nathusii LC - IV Common x 13,2-23,5 % 12 Pipistrellus pipistrellus LC - IV Common x 1,5-11,8 % 13 Pipistrellus pygmaeus LC - IV Very common x 1,5-11,8 % 14 Plecotus kolombatovici LC DD IV Common - 15 Plecotus macrobullaris NT DD IV Common - 16 Rhinolophus blasii NT VU II, IV Rare - 17 Rhinolophus euryale VU VU II, IV Common - 18 Rhinolophus ferrumequinum NT NT II, IV Very common - 19 Rhinolophus hipposideros NT NT II, IV Very common - 20 Tadarida teniotis LC - IV Common x 1,5-2,9 % 21 Vespertilio murinus LC - IV Rare x 1,5-2,9 %

22 periodic bat activity monitoring and monitoring of important underground sites in in compliance with the results of bat monitoring in 2013 bats use the Project area mostly during seasonal migrations (late spring, early autumn) higher activity at Velika Glava continuous bat detector monitoring - higher activity also in June and August during autumn, bat activity gradually decreases, despite suitable weather observed until the end of November

23 February March bat fatalities at 18 out of 19 WT June, July, August, September and October 2014

24 March April - low bat activity and a low risk of bat fatalities May - bat activity increased, but smaller number of bat fatalities was found (foraging at lower heights) June - first bats fatalities were recorded (pregnant females) July - bat activity decreased (late pregnancy and first week after birth) end of July - first fatalities were again found, higher activity (youngs start to fly) August - October - number of bat fatalities increased (autumn migrations) November - bat activity almost absent, no fatalities found (the end of autumn migrations)

25 Correlation to weather conditions The need for implementation of protection measures for bats fauna during WF operation is correlated with the level of their activity 1. in space (e.g. habitat type), 2. time (e.g. time of the year, night/day) 3. in relation to weather conditions (ambient temperature, wind speed, precipitation). Key factor - A substantial proportion of bat fatalities occur during relatively low wind speed and temperature above 10 C.

26 90% recorded bat activity Max. wind speed based on avg. 10-min values (m/s) June ,2 16,8 July ,6 17,8 August ,1 18,4 September ,3 14,0 October ,6 15,0 Min. temperature based on avg. 10-min values ( C)

27 Conclusion detailed bat surveys as part of EIA are neccesary to assess possible impacts on resident and migrating bats and collision risk bat activity between sites and species wind tolerance may significantly differ effective thresholds for cut-in wind speed and temperature should be determined on a case-by-case basis with good understanding of spatial and temporal variability of bat activity in relation to environmental conditions, optimal site-specific mitigation measures can be determined - minimizing the number of bat fatalities as well as power loss in energy production at the same time As well as during previous surveys at WF Danilo, periodic and continuous bat activity monitoring are being continued as well as carcass searches