Post-Construction Monitoring Report

The Post-Construction Follow-Up Plan (PCFP) for Wolfe Island is a state-of-the-art monitoring program, and is the most comprehensive program in Canada.

The PCFP requires bi-annual monitoring reports be prepared and submitted to Environment Canada, Ministry of Natural Resources, Natural Resources Canada and to Ducks Unlimited Canada for review and comment.

Data collected during the monitoring work is done professionally, objectively and without bias. The monitoring reports are prepared by third-party experts who have extensive experience in post-construction monitoring programs.

The PCFP ensures that any potentially significant unanticipated adverse environmental effects are identified if they occur. It also ensures the appropriate agencies are involved in the analysis of the monitoring results.

We proactively post the reports, along with Environment Canada and the Ministry of Natural Resources’ comments on the report, to our website for the public to view.

December 16, 2011

Summary of Monitoring Results

This report, the fifth in a series, contains the results of the post-construction monitoring program for the period between January 1 and June 30, 2011. Consistent with the schedule for post-construction monitoring outlined in Section 5.1 of the Post-Construction Follow-Up Plan (PCFP) for Bird and Bat Resources for the Wolfe Island Wind Plant (revised February 2010), field surveys conducted during the Reporting Period included:

bird and bat mortality monitoring
disturbance effects monitoring – wintering raptors
disturbance effects monitoring – staging and foraging migratory waterfowl
disturbance effects monitoring – breeding waterfowl
disturbance effects monitoring – breeding grassland, woodland and marsh birds

Mortality monitoring was carried out by employees of Wolfe Island Wind Monitoring, an independent consulting firm, according to a schedule and methods prepared by Stantec that were based on the PCFP. In addition to carcass searches, trials to determine various corrective factors for searcher efficiency and scavenging rates were conducted during the Reporting Period.

Bird Mortality Monitoring
A total of 31 carcasses of 20 bird species were collected during the Reporting Period.

Seven raptor and three Bobolink fatalities were recorded within the search areas over the course of this Reporting Period. The estimated mortality rate (after applying correction factors) for all birds is 1.72 birds/turbine (0.74 birds/MW) for the Reporting Period. When combined with the results of the July to December 2010, the annual mortality rate can be estimated, and has been calculated to be 10.0 birds/turbine (4.34 birds/MW).

The annual bird mortality rate of 4.34 birds/MW is lower than that observed at the Maple Ridge, New York facility (5.81 birds/MW) in 2006 (Jain et al., 2007), and slightly higher than the rate observed at Maple Ridge in 2007 (3.82 birds/MW; Jain et al., 2009). The Maple Ridge facility is located approximately 75 km south of the Wolfe Island Wind Plant. The Wolfe Island mortality rates are within the mortality range of 0 birds/MW to approximately 14 birds/MW reported by The National Wind Coordinating Collaborative (“NWCC”, Strickland et al., 2011) in their review of fatality rates at 63 North American wind facilities. When comparing numbers, it is important to note that most, if not all of the studies at Maple Ridge and those summarized in the NWCC report did not include winter mortality monitoring, and therefore any fatalities occurring over the winter months were not included in annual mortality rates. The data for the Wolfe Island Wind Plant includes winter fatalities.

The results of the first year of post-construction monitoring indicate that the annual raptor and vulture mortality exceeded the notification threshold identified in the Follow-up Plan. TransAlta, in consultation with MNR, developed and initiated a response plan, which involved supplementary studies of raptor and vulture behaviour in the fall of 2010 and spring of 2011, the results of which are provided in this monitoring report.

Bat Mortality Monitoring
A total of seven carcasses of two bat species were collected during the Reporting Period.

Correcting for searcher efficiency, scavenger and other removal rates, and percent area searched, the seven recovered carcasses represent an estimated total bat mortality rate for the Reporting Period of 0.48 bats/turbine (0.21 bats/MW). When the results of the Reporting Period (January to June) are combined with the estimated mortality rate for the period July to December 2010 (9.50 bats/MW), the estimated annual mortality rate of 9.71 bats per MW is within the range of mortality reported by NWCC (Strickland et al., 2011) (0 to 39.7 bats/MW/study period).
The annual bat mortality rate is below the adaptive management threshold of 12.5 bats/MW as identified in the Follow-Up Plan.

Although the bat mortality rate is below the threshold, TransAlta has proactively developed and implemented a research program to mitigate and reduce bat mortality. The research was implemented during the 2011 fall bat migration season when the majority of fatalities occur. The research includes operational control of selected turbines during night time hours under low wind conditions. Results from this research will be presented in the 6th monitoring report that covers the period from July 1 to December 31, 2011.

Winter Raptor Surveys
During the 2010/2011 winter raptor surveys, maximum numbers of observations during any one survey include 31 Rough-legged Hawks (December 8), 15 Red-tailed Hawks (November 9), 16 Northern Harriers (December 16) and 4 American Kestrels (Nov 9 and Feb 17). The largest number of Bald Eagles (3 observations) was observed on January 20, 2011. Peak numbers of Short-eared Owls were observed in 2011, with up to 45 individuals observed on a single survey (January 6). The abundance of Short-eared Owl observations suggests Wolfe Island remains an important and productive wintering area for this species.
The results from the winter raptor surveys during the Reporting Period demonstrated that raptor abundance had increased significantly from the 2009/2010 season, but numbers were lower than that observed 2006/2007. Differences in raptor density observed within the study area between 2006/2007, 2009/2010 and 2010/2011 seasons are reflective of observations throughout the Kingston area and across southern Ontario. Differences observed between the pre- and post-construction monitoring are attributed to natural variability.

Staging and Foraging Waterfowl
In total, nine species of waterfowl were observed foraging inland during the spring 2011 post-construction monitoring; all species were either geese or dabbling ducks. Species composition in 2011, dominated by Canada Goose, was very similar to that observed during the 2007 pre-construction monitoring. Overall, the total number of waterfowl days was higher in 2011, totaling 99,141 compared to 57,906 waterfowl days in the spring of 2010 and 85,219 in the spring of 2007. Geese were routinely observed foraging in fields that contain WTG’s. Overall, the results suggest that proximity to wind turbines is not an important factor to the foraging field selection of waterfowl.

Waterfowl use of offshore staging areas, as measured through aerial surveys, was very similar in the spring of 2008, 2009, 2010 and 2011; waterfowl days in the spring of 2011 was 3% larger than that of 2010 and 2009 and 12% larger than 2008. Overall, it is apparent that waterfowl remained abundant in each sector and each of the major staging areas each year, with no apparent avoidance of the wind plant during construction in 2009 or operation in 2010 and 2011.

Breeding Waterfowl
Breeding waterfowl surveys found a total of 5 species of waterfowl, all of which were expected to be breeding within the five major wetlands in proximity to WTG’s. Mallard was the most common species, followed by Canada Goose), while other species were observed in lower numbers across the five wetlands. The Bayfield Bay Marsh route had the largest number of breeding pairs observed, all of which were Mallard. Overall, the waterfowl breeding pairs surveys found populations of breeding geese and/or ducks in each of the major wetlands that are in proximity to WTG. The results of the surveys did not provide any indication that waterfowl avoided nesting in proximity to WTG’s.

Breeding Grassland, Woodland and Marsh Birds
Overall, the grassland surveys indicated that grassland breeding birds remained common throughout the wind plant area. The grassland point counts, repeated during pre and post-construction monitoring, recorded an apparent decrease in breeding density in some grassland species. However, decreases were not observed for the same species through paired point count surveys and grassland area searches. Results of the grassland area searches, which surveyed large portions of grassland habitat in the study area during both pre and post-construction, did not demonstrate a decrease in grassland bird density. A wind turbine avoidance effect was not observed for grassland species through paired point count data, as densities for most species were similar at 0-100m and 100-200m from wind turbine bases.

Relatively high breeding bird species diversity was recorded through area searches in the surveyed woodlands in proximity to WTGs. For most species, point count data suggest there was little change in breeding densities between 2008 pre-construction and 2011 post-construction surveys.

The abundance of wetland breeding birds, as measured by the point counts and area searches, remained similar between pre and post-construction surveys. Results of the wetland point counts and area searches suggest the population of breeding birds in the five major wetlands in proximity to WTGs remained relatively consistent between pre and both post-construction surveys.

To read the Executive Summary in its entirety, please click on the Current Report link below.

For more information about past research we’ve done relating to bat mortality, please click here.