Scientific Issues
PRESENTATION SUMMARY: - Current state of knowledge. - Peer review. - Avian and bat mortality, habitat fragmentation and disturbance. - Prairie grouse and grassland-sage-steppeobligate songbirds. - Where do we go for info? - Scientific tools. - Additional tools needed. - NWCC. -1-
Current State of Knowledge: Birds
• Except at Altamont, mortality appears to be low – averaging 2 birds/turbine/yr., 0.33 raptors/t/yr. • Nationwide mortality estimate, however, not based on especially robust research – 12 study sites mostly in W. and Mid-W.
– There are biases associated w/ these studies.
• Probability of available and detected mortality: rate carcass removal by scavengers, predators, and searcher efficiency are biases. E.g., detection rate for passerines ~= 25%. • Observed fatality rate may be bias (e.g., surveys done once/2 wks.) • Adjusted fatality rate – the larger the correction factor, higher the uncertainty w/ the estimate.
• Habitat fragmentation and disturbance likely greater problem than strikes. Pitting wind against grouse and grassland-sage-steppe obligate songbirds. -2-
Current State of Knowledge: Birds, cont.
Questions:
• Is weather key issue for birds at turbines like for birds at communication towers?
• Are red strobe lights unattractive to birds in bad weather? • Are lights that all “fire” simultaneously less attractive to birds?
Concerns:
• Have lots observational data vs. little empirical data. -3-
Current State of Knowledge: Bats
• Only know tiny amount compared to birds – 1/1,000! (Merlin Tuttle, BCI) • Strikes appear be problem wooded ridge tops or forested/wooded areas adjacent turbines. Detection rates even poorer for bats than for passerines. • Until recently, highest mortality at Buffalo Mt., TN (3 turbines) – estimated mortality ~30 bats/t/yr. • Now highest mortality Backbone Mt., WV (Mountaineer, 44 turbines) – estimated 1,600- >4,000 bats 2003. Estimates similar 2004. • No listed bats yet documented. • Have attention FPL and AWEA. Formed w/ FWS Bat-Wind Collaborative. Ed Arnett, BCI, PI. • Movement over and along/across ridges big issue esp. during migration. Non-migratory feeding also big issue – striking nonmoving blades, towers. -4-
Current State of Knowledge: Prairie Grouse
• “Prairie Grouse”: Greater and Lesser Prairie-chicken, Atwater’s Pc., Gunnison and Greater Sage-grouse, Columbia Sharp-tailed Grouse • Have good, developing database avoidance tall structures: oil wells, power poles, buildings (e.g., pumping stations). Lack good strong database on “prairie grouse” avoidance wind turbines. However, Frank Hall (CA F&G) about to release data. • Strong list experts working on issue: Stephanie Harmon (FWS), Kevin Kritz (FWS), Rob Hazlewood (FWS), Robert Robel (KS), Cameron Aldridge (ALB, CAN), Clait Braun (CO), Jack Connelly (ID), Pat Deibert (FWS), Frank Hall, Christian Hagan (OR), Rob Manes (KS), Michael Patten (OK), James Pitman, Don Wolfe (OK), others. -5-
Current State of Knowledge: Grassland and Shrubsteppe Avifauna
• Grassland and Shrub-steppe Avifauna:
– Displacement and avoidance by Golden Plovers, Lapwings, and Curlews documented much as 0.5 mi. from wind facilities Europe. – In U.S., Bobolink, Red-winged Blackbird, Savanna Sparrow, and Sedge Wren nested 4x densities 600 ft. from turbines than closer (densities beyond 600 ft. not evaluated). Size avoidance zones yet undetermined. – Sage-steppe-obligate songbirds, e.g., Sage Sparrow, Brewer’s Sparrow, Sage Thrasher, and Black-chinned Sparrow all showing pop. declines, suggesting need for studies wind impacts. – By placing turbines in cropland habitats vs. native prairie grassland and sage-steppe habitats, may avoid problems. -6-
Peer Review
• Service (Manville) prepared briefing for members NWCC/WW which was discussed Nov. 5, 2004 at meeting. • Review varies from types and levels peer review such as in-Service peer review (including surname), to review for publication professional scientific journals. • While most sound review is by team (>2) professional reviewers (e.g, reviewers w/ Ornithological Council, others for Journal Wildlife Management or Auk, Wilson Bulletin, etc.), Service acknowledged that these reviews can take considerable time b/w receipt manuscript and final publication. Peer referee vs. peer review also discussed. • Service bottom line: to make document (e.g, pilot study, research protocol, research design) credible, needs to be reviewed by professional peers, preferably including Service biologists. • Discussion will continue at future meetings NWCC. -7-
Where Do We Go for More Information About Wind Facilities and Wind Development?
• NWCC/WW, NREL, AWEA, CanWEA (Canadian Wind Energy Assoc.) websites excellent sources. • Manville library -- European literature, “prairie grouse” and songbird info, virtually all the materials from U.S. used to develop our voluntary guidance, notes from NWCC/WW meetings, conference proceedings, etc. Library card required! • Regional info, pubs., databases – including at Field Offices. • Service migratory bird website needs to have wind info available. Something to work toward in immediate future. -8-
Scientific Tools
• Doppler weather radar (WSR 88D) – NEXt generation RADar (NEXRAD). Deals w/ reflectivity and velocity. Only detects moving targets. ~150 doppler weather sites nationwide. Drs. Janet Ruth and Rob Diehl will be doing NEXRAD study in SW. Should better answer Q’s about use of technology and stopover habitats. • BIRDRAD – high resolution, Furuno 50 kW marine radar. Has echo trail feature, can use GPS data for tracking targets. Can tilt radar 30o from horizon. Get target direction and speed. • Thermal imagery – using video cams, imaging body heat. Expensive but can track actual individual targets (bats) at facility. -9-
Scientific Tools, cont.
• Combining thermal imagery w/ fixed vertical bear radar. Can get altitude, movement, flock size. Can identify groups of birds. Helps to “ground truth” findings from one technology. • Night vision scopes – expensive to buy, but can rent. Some utility. • Acoustic monitoring – to detect avian chirp (chip) calls, using voice recognition software. Use Anabat monitoring for sonar detection of bats. • • • • • GPS, GIS mapping. Ceilometers. Even moon watching – on low budget. If use one technology, important to “ground truth” w/ another. SEE Ron Larkin’s summary from NWCC/WW Research Meeting V workshop. -10-
Additional Tools Needed
• Nationwide database on migration, ideally including migration stop-over sites, corridors/flyways used, flight altitudes, flight behavior.
– Janet Ruth/Rob Diehl’s doppler weather radar study begin to get handle. – Deanna Dawson USGS study in NE also begin to develop migration database.
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Voluntary nationwide mortality database like being finalized in APLIC’s template for Avian Protection Plan. Nationwide GIS overlays.
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Assess European “sensitivity index” by Franz Bairlein, Inst. Avian Research, Germany. Help to determine where not put turbines. We want compare our site ranking process to their evaluation process.
Need consistent, robust, scientifically sound, peer-reviewed pre- and postconstruction monitoring protocols, for latter assessing both mortality and behavior. Opportunity for FWS to peer-review. May need long-term (>2-3 yrs.) monitoring. From biological perspective, is there “acceptable” level mortality (MBTA aside). How do we respond to this question? -11-
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National Wind Coordinating Committee
• Many key scientists, Federal biologists and technicians, most research consultants, NGOs, industry members of or affiliated w/ NWCC’s Wildlife Workgroup. • Peer review issue before WW. Ultimately, should help in producing more credible “product.”
• Continues be excellent repository for research and scientific information. Info easily accessible, http://www.nationalwind.org
• More scientific workshops planned for 2005 and beyond.
• Service anticipates continued membership on NWCC/WW. -12-