TransAlta has released its 3rd Post-Construction bird and bat monitoring report for the Wolfe Island Wind Plant. The plant completed one full year of operation of all 86 turbines in July 2010. “TransAlta’s Post Construction Follow-Up Plan (PCFP) is essentially a 3 year monitoring program to Assess the direct (mortality) and indirect effects (habitat, avoidance, displacement) to birds and bats from operating wind turbines, that would trigger an adaptive management response,” according to Garry Perfect, TransAlta Environmental Specialist. The PCFP ensures that any potentially significant unanticipated adverse environmental effects are identified if they occur. Perfect’s role it is to ensure that the prescribed monitoring activities at the Wolfe Island wind Plant are completed.
According to PCFP all 86 towers at the Wolfe Island plant are searched once per week including winter surveys with year round carcass searches including scavenger removal and searcher efficiency trials The reports are submitted to Environment Canada, Ministry of Natural Resources, Natural Resources Canada and to Ducks Unlimited Canada for review and comment.
“The latest report indicates that 66 carcasses of 28 bird species including 10 raptors were collected during the January 1 and June 30, 2010 reporting period and 12 during the July 1 and Dec. 31, 2009 reporting period),” Perfect said . “The estimated mortality rate for all birds is 6.39 birds/turbine (2.78 birds/MW). When combined with the July-December 2009 period, the annual mortality rate has been calculated to be 13.39 birds/turbine, (5.82 birds/MW). The 5.82 figure is well below the adaptive management threshold of 11.7 birds/MW identified in PCFP.”
” However the raptors mortality rate for one year slightly exceeded the .09 MW threshold (0.12) triggering adaptive management measures,” Perfect said. “One to do a raptor behavioural study to help identify factors that may be the cause. A work plan and methodology was developed , reviewed by Environment Canada and MNR. Implemented in August 2010 it will wrap up in May 2011.” (It will look at flying characteristics on migrating birds and those staging in the area, ( distance to lakeshore, towers, habitat features that are close to where birds are spotted.) ” We will collate that information to weather conditions (wind speed, direction, etc.) to determine when raptors fly more often and when not perching to try understand conditions directly related to mortality and find ways to minimize those rates”
(In the recent study, seven red-tailed hawks, one osprey, one northern harrier and one turkey vulture made up the group of 10 raptors. The majority appeared to be individuals migrating through the study area.) “We had 22 raptor mortalities over the one year period, 5 were breeding , 1 was a wintering bird. The rest were considered migrants based on when carcasses were found . Mortality pulses are late summer/fall, mid April migrations. As the year round monitoring goes on, if two raptor carcasses are found in a consecutive 6 week period, I am notified and inform NMNR and ECanada . If it continues for a full year we will exceed our .09 threshold. It is a check as we go on our day to day monitoring and avoids surprises at the end of the year. We will look at all the data (weather wind etc.) Once understood we will devise next steps.” Perfect added that at the Melancthon II Wind Plant in spite of raptor mortalities, data indicates no detectable difference in raptor numbers. Do fledglings offset the number? ”
When it comes to Bats, Perfect said 34 bat carcasses of 3 different species were collected during the reporting period. . The annual mortality rate of 8.69 bats/MW while the TransAlta PCFP threshold for adaptive management follow up plan is 12.5 bats/MW. “However 15% of the 214 bat fatalities recorded during year round monitoring on Wolfe Island fell within the spring months peaking in the 1st week of May.. So even though the number is under the threshold we are implementing a research program aimed at reducing fatalities. It will include adjusting the ‘cut in’ speeds of the turbines ( 3.5metres per second of wind speed) to a 4.5 or 5.5 metres per second wind speed at night in low wind periods when bats are most active at the WI Plant. Trans Alta has done similar research in Alberta realizing a significant drop in bat mortalities.. ” according to Garry Perfect. “We are also participating in a research project being conducted by Erin Baerwald (University of Calgary) to further understand bat migration characteristics. Migratory bat carcasses are sent for DNA and Isotope analysis with an objective of determining points of origin. Where did they come from. We are also sending bat carcasses to U of Guelph for study. Thus far no sign of White Nose syndrome although it has been found in Ontario.”Garry Perfect concluded.
Garry Perfect will present the findings of the report to WIRE (WI Residents for the Environment). The report has been received by Frontenac Islands Council. The Wolfe Island Post Construction Monitoring report can be found at: http://www.transalta.com/facilities/plants-operation/wolfe-island/post-construction-monitoring