Bird collision risk being studied
Kim Gaffett, the resident Naturalist for the The Nature Conservancy and resident bird expert, is among a group spearheading a first-of-its-kind study to track the collision risk of two particular species of birds that migrate near the Block Island Wind Farm. The behavioral study is being conducted to determine how these migratory birds react to wind turbine towers, utilizing data from VHF radio transmitter signals.
Gaffett, who is working with Scott Comings of The Nature Conservancy and Dr. Peter Paton from the University of Rhode Island’s Department of Natural Resources Science on the research project, was granted unanimous approval for installing a temporary 30-foot tall pop-up tracking telemetry tower on TNC land at Black Rock (Plat 12, Lot 14) from July 1 to Sept. 15 at a recent Town Council meeting. Dr. Paton said an existing tower at the Southeast Lighthouse will be used for triangulation purposes, and plans are to place a third tower on either an offshore buoy or a wind turbine platform, pending approvals.
According to Dr. Paton’s May 19 request submitted to the Town Council, the temporary tower equipment “will test the ability of (digital) VHF transmitters to assess fine-scale movements of the roseate tern and piping plover near the five wind turbines.” The group is studying birds that have been tagged with radio transmitters at colonies in Buzzards Bay, Massachusetts; Great Gull Island in New York, and in coastal areas of Rhode Island and Massachusetts.
Dr. Paton stated in his request to the Council that the temporary galvanized steel tower “will take approximately half a day to construct” and deconstruct. It will “operate 24 hours per day using one 120-watt solar panel and two 12-volt deep cycle batteries.”
“It’s a temporary thing — meant to gather information,” Gaffett said to the Town Council. “Dr. Paton is monitoring for bird activity in the area of the wind turbines.” Gaffett said the research will be geared toward tracking birds wearing an Avian NanoTag, a radio transmitter, for research purposes during the project’s research period.
“So, it’s not really to track the number of birds, but the number of birds that are tagged, correct?” asked First Warden Ken Lacoste.
“Yes,” said Gaffett. “Well, there are two things going on: tracking tagged birds; but there will also be monitoring to track birds that are not tagged.” She noted that two towers, one located at the Southeast Lighthouse and the other at Frankie and Gordon Smith’s property, have each recorded about 80,000 to 100,000 birds over the past two years. “If you’re a scientist, it’s important,” she said.
Dr. Paton told The Block Island Times that the research being conducted is to study “the collision risk between birds and the turbines. It’s the first time this type of study has been attempted anywhere on the planet.”
Paton said the focus will be “to understand how migratory birds react to wind turbines, particularly under conditions when it is difficult for observers to see birds, like at night, during bad weather, etc. We do this by placing transmitters on birds that emit a signal every five seconds. The antennas (on the towers) detect the signal. By having multiple antennas detect a signal, we can triangulate the position of the bird to accurately track its flight path.”
“The transmitters are small, and glued on the backs of birds,” said Paton, explaining the process and technology required. “The transmitters eventually, after 6 months or so, fall off. As a bird flies by, the towers have a receiver that automatically detects the transmitters. The unique aspect of this technology is that we use a conventional VHF radio signal, but each transmitter has a unique digital signal, so thousands of birds can be on the same frequency.”
Paton said that information gleaned from the study “will be provided to federal agencies, written up in a technical report, possibly submitted to an academic journal, and presented at meetings. Hopefully we will provide information to federal agencies that will be useful for guidelines for site placement and operation of offshore wind turbines.”
Paton noted that “piping plovers are federally listed as threatened, and roseate terns are federally endangered, so there is considerable interest in both species — particularly from federal agencies such as the United States Fish and Wildlife Service and the Bureau of Ocean Energy Management, which is in charge of leases for offshore wind.”
“Block Island provides a unique opportunity to investigate bird responses to offshore wind turbines, since it is the only offshore wind facility in North America,” said Paton. “Researchers in Europe have used radar to investigate collision risk, but radar will not work for terns or plovers, as one cannot identify species based on a radar signal. Thus, this is the first attempt to determine collision risk for these threatened and endangered species under a variety of environmental conditions.”