VINALHAVEN, Maine — The birds are safe. The conclusion of a recently released study about how many birds fly into the three industrial wind turbines on Vinalhaven: Not many. Fewer than 10 per year, ornithologist Richard Podolsky said.
Podolsky was hired by Fox Islands Wind LLC to do a 28-month study on the wind turbines’ effect on local eagles and osprey. The study was required by the town’s wind ordinance. In his time on the island, he found two bird corpses near the windmills — and he can’t say for sure that the turbines killed them. After all, “birds die all the time,” he said.
Both bird corpses were much smaller than eagles or ospreys. One was a golden-crowned kinglet and the other was a Philadelphia Vireo.
Because the turbines were put on rocky terrain on top of an old quarry, the site is unattractive to birds, Podolsky said. This was the main reason the mortality rate was so low.
“What puts birds at risk is the number of birds coming and going from the site. If you have a site with very little to attract birds, you have lower traffic. It’s like car collisions. There are more car collisions when there are more cars moving. The same is true with birds.”
Podolsky, who lives in Rockport, has studied more than 70 wind sites nationwide for his business, Avian Systems. Nationally, three to seven birds are expected to die per turbine per year, he said. New England typically has a higher bird death rate than western states because those states mostly put their wind farms in fields where birds don’t twitter about. Even when compared to other New England wind power sites, Vinalhaven’s results are good, he said.
“If this was an average New England site, with three turbines, we would expect to see 15 to 20 birds die [yearly], but I think it’s at the lower end. It’s closer to two to three birds per turbine because it has very low bird use and low bird traffic in that air space,” Podolsky said. “It’s not quite as good as a Kansas wheat field, but it’s not a high traffic area. I think this project will continue to perform at a low mortality rate.”
The study started in September 2008 before the turbine construction started and wrapped up in December 2010. This allowed researchers to watch the birds for eight months before the turbine construction, two months during land clearing, four months during construction and 14 months of true wind turbine operation.
The scientists sat on the land or poked around looking for bird carcasses for more than 1,000 hours in that time.
The study focused on eagles and osprey on the island. Scientists found that there are about 80 eagles on Vinalhaven during peak eagle time — they don’t live on the island year round — and about 25 osprey at their peak time on the island.
Of those birds, about six eagles and two osprey “might be expected to pass within a three-acre footprint occupied by the thee GE wind turbines during daylight hours each year,” the study states. More importantly, the study states, the “reasonable expectation is that most eagles and osprey passing the project site will be able to detect and avoid the [turbines] because both species, and most raptors, essentially fly only during daylight hours and typically do not fly during fog and rain.”
When the project started, there was not much fuss about birds on the island, according to the Maine Audubon Society and Bangor Daily News archives.
According to a wind company official, that’s because the firm knew from the start that the birds didn’t like flying near the old quarry where the turbines were erected.
“Part of the reason there wasn’t much hullabaloo was we did a lot of research and knew the avian impact would be pretty small,” said Fox Islands Wind LLC CEO George Baker. “We were careful about doing studies ahead of time. Birds don’t like high rocky ledges. There isn’t much there for them. That’s exactly where we built the turbines.”
The impact was even less than the company originally predicted, Baker said Tuesday.
“The bottom line is, when you turn the lights on, something dies,” said Eric Hynes, the staff naturalist for Maine Audubon.
“Nature is interconnected. Certainly, that is an acceptable loss considering what’s gained. You have to be realistic about it, and that’s a reasonable loss,” he said of the handful of lost birds on Vinalhaven per year.
The Vinalhaven Planning Board will discuss the study at its meeting 7 p.m. Wednesday, May 11, at the town office.