Greg Johnson and Chad LeBeau, WEST, Inc., Matt Holloran, Wyoming Wildlife Consultants

Transcription

1 Greg Johnson and Chad LeBeau, WEST, Inc., Matt Holloran, Wyoming Wildlife Consultants

2 Project Funding Horizon Wind Energy is primary funding source. Iberdrola Renewables provided funding to purchase half of the radio collars. The Bates Hole/Shirley Basin Local Sage-Grouse Working Group is paying for all flight time for the project with funds obtained from the Wyoming Game and Fish Department. WEST obtained a $100,000 grant from the Department of Energy (DOE) for the project.

3 Background Much debate has occurred recently regarding the potential impacts of windenergy facilities on greater sage-grouse. Although numerous data have been collected on response of prairie grouse to other developments (e.g., oil & gas, powerlines, roads), no data have been collected on sage-grouse response to wind energy.

4 Study Objectives: Determine locations of seasonally selected habitats within the influence of the wind energy development project (e.g., nesting areas, early and late season brood rearing areas, wintering areas). Determine the population impacts of the wind energy project on greater sage-grouse within the influence of the project (e.g., survival, nest success, brood success).

5 Study Area Location: Carbon County, Wyoming, between the towns of Hanna and Medicine Bow.

6 Study Area This study is being conducted in an area with two proposed (Simpson Ridge and Pine Draw) and one existing wind-energy facilities (Seven Mile Hill). All of the Simpson Ridge project area is in a sagegrouse core population area as defined by the Governor of Wyoming. Existing wind project has 79 GE 1.5 MW turbines, constructed in 2008.

7

8

9

10 Methods - Lek Surveys Objective of lek surveys is to monitor long-term population trends. Lek search and survey methodology followed that outlined by the Wyoming Game and Fish Department. Survey area included all wind projects and 4-mile buffer. 3 fixed-wing aerial surveys. 3 ground visits to each lek.

11 Methods - Radio Telemetry Necklace transmitters weighing 22g, manufactured by Advanced Telemetry Systems (ATS), and with a battery life of 666 days, were used. Transmitters were equipped with mortality sensors.

12 Methods - Radio Telemetry Female greater sagegrouse were captured by spotlighting and use of hoop nets on roosts surrounding leks in April. 116 females radiocollared for study (75 in spring 2009; 41 in spring 2010).

13 Birds were tracked mostly from the ground using hand-held receivers (ATS). Aerial surveys were conducted to locate missing birds and to locate birds during winter. Bird locations were determined by triangulation and homing until visibly observed. Each radio-marked grouse was relocated at least twice each week during the pre-laying and nesting period, once a week during brood rearing, approximately once every two weeks during fall, and once a month in winter.

14 Nest locations were documented using homing techniques. For each nest, data were collected on timing of incubation and nest success. All nest locations were mapped using a GPS. Clutch size was determined by counting eggshells following a successful hatch or the destruction of the nest.

15 Radio-marked hens with broods were located at least once a week to determine early brood rearing habitat. Chick survival was assessed visually or by interpreting the female s reaction to the researcher.

16 Fledging success was determined days post hatch. Conducted with spotlights on two consecutive nights. Chick survival was assessed visually.

17 Results Twelve leks were located within the Simpson Ridge Wind Resource Area (WRA). Mean lek size was 39 males in 2009 and 23 in 2010.

18 Results Lek ID Distance to nearest turbine 2008 male Count 2009 male 2010 male count count Missouri John 0.85 mi Pine Draw 0.38 mi Commo mi Declines in male lek attendance noted region wide

19 Telemetry Of the 116 female sagegrouse radio-collared for this study, 79 (68%) were adults and 37 (32%) were yearlings.

20 Capture Locations All females were captured near seven of the project area leks. 66 females were captured near or within the Simpson Ridge WRA. 50 females were captured near Pine Draw WRA and Seven Mile Hill existing wind energy facility.

21 Nests 69% of all radio marked hens initiated nests. Nest success was 37% in both 2009 and Nest success was on the low side compared to other sage grouse studies in Wyoming (33-72%).

22 Nests 18 nests were initiated within one mile of wind turbines at the Seven Mile Hill project. The four closest nests were located 130, 134, 174, and 278 m from the nearest turbine. Four of the 18 (22%) were successful. Primary cause of nest loss was predators.

23 Broods Early brood locations were obtained from hatch until June 30. Late brood locations were obtained July 1 through August 15. Early brood success (first 14 days) was 100% in 2009, while fledgling success (35 days posthatch) was 63%.

24 Summer Range Over 200 summer range locations were recorded from late June to late September Summer locations were located throughout the project area.

25 Fall Range Over 100 fall locations were recorded from October 1 late November. Fall locations were located throughout the project area.

26 Winter Range Over 200 winter range locations were recorded from December 1 to early April. Winter locations were located throughout the project area.

27 Mortality Annual survival was 53% in Survival in 2010 through mid June was 76%. Mortalities occurred throughout the study area. Most of the deaths were attributed to predation, but three were confirmed to be infected with West Nile Virus.

28 Telemetry locations Over 2,300 locations were obtained from the start of the study in April 2009 to June Data indicate study area population is nonmigratory.

29 Discussion Population trends as estimated from lek counts were consistent with somewhat downward tends observed in Wyoming during 2009 and Nesting propensity (the number of females initiating nests) was low relative to other sagegrouse studies conducted throughout Wyoming since 1994 (74-93%).

30 Discussion Nest success estimates were within the range of observed rates, but generally on the low side of the range for other sage grouse studies. Fledging success (63%) was on the low side of the range (60-80%). Annual survival (53%) was within the range of other studies.

31 Conclusions The data provided in this presentation should be considered preliminary and are not meant to provide a basis for forming any conclusions regarding potential impacts of wind energy development on greater sage-grouse. Although the data collected during the initial phases of this study indicate that greater sage-grouse may continue to use habitats near wind-energy facilities, research conducted on greater sage-grouse response to oil and gas development has found population declines due to oil and gas development may not occur until as many as four to 10 years post-construction. Long-term data will be required to adequately assess impacts of wind-energy development on greater sage-grouse.

32 Acknowledgements Horizon Wind Energy - primary funding source. Iberdrola Renewables - radio collars. Shirley Basin/Bates Hole Local Sage-Grouse Working Group - flight time. U.S. Department of Energy - $100,000 grant PacifiCorp - access to the Seven Mile Hill facility for study purposes. Troy Rintz, Jason Herreman, Victoria Poulton, Greg Leighty WEST field biologists. Scott Gamo and Mary Flanderka, WGFD, Jack Connelly, IFGD, and Christian Hagen, ODFW, provided valuable comments on protocol.