New England

In the winter months, huge "rafts" of Common Eiders feed on mollusk beds in Nantucket Sound. This raft contained roughly 20,000 individual ducks. Only the bright white drakes (males) are visible in this photograph.

Table of Contents:

Introduction
Renewable energy source needed
Mass Audubon’s position on wind farms
Birds and wind turbines
Let’s not throw caution to the wind
Photograph credits

Keywords: wind turbines, offshore wind farms, renewable energy, Nantucket Sound, birds, roseate terns, wintering waterfowl

Introduction

Windmills have been a part of the Nantucket landscape for roughly three hundred years. Therefore, some find it ironic that a bold, new proposal to build 130 windmills on Horseshoe Shoal in the waters off Nantucket has generated such controversy. It makes one wonder if the construction of the weathered matriarch that still dominates the skyline atop Mill Hill on the southwest side of the town of Nantucket -- the oldest operating windmill in the United States -- created the same flap in 1746. Did the residents along Prospect Street protest mightily when they first heard the news that a 50 foot-tall windmill was going up in their back yard?

Of course, the state-of-the art turbines today are vastly different machines from the “ye olde” model on Nantucket. For one thing, the new-age turbines proposed for the Sound would be 425 foot-tall, finely tuned, carbon steel behemoths that, collectively, would produce 420 megawatts of electricity, not pounds of corn meal. Instead of standing alone as their predecessors did, the 130 wind turbines slated for Nantucket Sound would be deployed within an area encompassing 25 square nautical miles. This array would represent the first offshore wind farm in the United States and it would make the Cape Wind project one of the largest in the world. Hardly the realm of the 18^th Century!

Renewable Energy Source Needed

Arguments regarding the Cape Wind project have become highly charged and the opinions highly polarized. But, whatever those opinions might be, few of us would refute the fact that the power-source status quo just is not working. We only need to glance back to spring of 2003, to the oil spill around Buzzards Bay to find the most recent local reminder of this disturbing reality. And, bear in mind that the roughly 100,000 gallons of oil spilled from Bouchard Barge B120 were bound for the Cape Cod Canal power plant in Sandwich, an antiquated oil-fired facility that, like all of its kind, produces copious volumes of greenhouse gases. If that oil hadn’t leaked into the sea, its byproducts would have been released into the air. Which would have been the greater of the two evils? Some might say the latter. Either way, nature loses.

Oil has ruled the planet since the 18^th century when Nantucket became the“Whaling Capital of the World.” Whale oil from the great Nantucket whaling fleet lit nearly every city on the planet. In the 1700’s, Nantucket was nearly as synonymous with oil as Saudi Arabia is today. The only difference is the type of oil being produced. As our overproduction of greenhouse gases continues to warm the atmosphere, and the possibilities of rising sea levels and mass biological extinctions persist, we humans may be approaching a crossroad at which we will be forced to make some abrupt changes to the way we conduct ourselves in the world in terms of both energy production and consumption.

Mass Audubon’s position on wind farms

Mass Audubon recognizes the dire need for renewable energy and has always promoted its development. Mass Audubon has also been a leading watchdog for wildlife for more than a hundred years. In order to come to terms with this apparent conundrum, we have followed a long-standing policy of basing our advocacy positions on the best science available and, when feasible, filling gaps in the data. As yet, an adequate body of data on which we can base an institutional opinion about the Cape Wind project is lacking.

In an effort to find the needed data, members of our Conservation Science Division staff began conducting avian surveys in Nantucket Sound in the late summer and early fall of 2002. The surveys are still underway as of this writing. Our studies focus on estimating the abundance and distribution of two groups of birds: terns and wintering waterfowl. We study terns because nearly half of the entire North American population of the federally endangered Roseate Tern breeds within 20 miles of Nantucket Sound, and waterfowl because a minimum of half a million wintering sea ducks spend six months of every year within the Sound. To review the most recently posted update of these studies or to read our Position Statement, visit www.massaudubon.org.

Mass Audubon asserts that we will need a minimum of three years of data to adequately assess the status of the species in question. We have already completed two years of tern studies and one year of waterfowl studies. Once we finish collecting the data, we will attempt to correlate those data with possible on-site, post-construction risks to the birds. By knowing before construction which species use the site, how, when, and in what numbers, we will be in the best possible position to make those correlations.

Mass Audubon is currently advocating for the creation of a standardized regulatory framework, based on the best available science, which would define the environmental review and siting protocols for all new wind farms. Such a framework would streamline the system by creating transparency within the process and it would inform both developers and regulators by providing guidance metrics. No one would appreciate such a structure more than local regulators, who, to date, have been left to their own devices with largely subjective, ad hoc guidelines. Such clarification would also level the playing field for all future projects. While this type of environmental review is new to most of us, and the learning curve is still steep, each new site evaluation will add to our collective body of knowledge. With each new study, the watchdogs among us hope to become more proficient at identifying sites that will sustain the lowest levels of environmental impacts.

Roughly half of the entire North American population of the federally endangered Roseate Tern nests on islands in Buzzards Bay, MA within 20 miles of the proposed Cape Wind project site.

Birds and Wind Turbines

What threats would wind turbines pose to birds within the Sound? We hope none. However, we have learned that within the past 30 years, millions of birds die annually in the United States alone as a result of striking tall objects (see http://www.towerkill.com/). The designed function of such structures doesn’t matter. They could be, for example, telecommunication towers, skyscrapers, or wind turbines, on land or at sea. The birds die simply because these vertical objects project into the birds’ airspace and they strike them. This does not mean that all birds that approach wind turbines collide with them. On the contrary, by best estimates, the numbers of birds that die from striking wind turbines are low, especially when compared to other causes of avian mortality, such as windows, cars, and house cats.

The one exception in the United States -- the fly in the ointment so to speak -- is the infamous Altamont wind farm sixty miles east of San Francisco, California. Here, hundreds of raptors die annually from collisions with wind turbines. However, this is a land-based wind farm and comparing the situation at Altamont to any offshore site would be like comparing apples and oranges. In general, comparisons between any combinations of wind farm sites should be made with care because each site is ecologically unique and should be evaluated on a case-by-case basis.

Each fall, just prior to embarking on migration, nearly the entire North American population of the federally endangered Roseate Tern congregates within 20 miles of the Cape Wind project site, at Monomoy Island National Wildlife Refuge and adjacent South Beach in Chatham, MA.

One critical difference between land-based wind farms and those offshore is the extent to which bird interactions can be monitored. We know what we know about land-based structures and their impacts on birds because of what we find on the ground after the fact. When birds strike these objects and fall out of the air, they come to rest within relatively close proximity of the tower bases, and the impacts can be measured simply by counting the dead birds found on the ground the next day. However, if birds were to strike offshore turbines during a storm or in dense fog or at night, we’d never know it; once the birds fell into the water around a turbine, they would be eaten or they would drift away before the storm abated, the fog lifted, or the sun rose.

We know relatively little about how birds might interact with offshore turbines. Studies in Europe have clearly demonstrated that seabirds can and do actively avoid wind turbines when they see them. This is not surprising given that most birds have superb visual acuity- much keener than human vision. It’s when the birds cannot see the turbines -- during inclement weather- - that they may get into trouble. Virtually all large-scale bird kills at telecommunication towers occur during inclement weather. Until we can gather the evidence that demonstrates that other tall structures --including turbines -- are not going to cause similar problems, we should use great care when selecting sites for new wind farms. This will be especially important in Nantucket Sound because Cape Wind has become the test case for offshore wind in the United States. All eyes will be upon us, and the precedents set here in Massachusetts will influence future projects elsewhere.

Let’s not throw caution to the wind

Wind energy is the fastest-growing form of energy in the world. Its time has come, as has the time for other sources of clean, “green” renewable power. However, developments made for the sake of the environment would be counterproductive if they came at the expense of wildlife. Aside from the biological implications, a catastrophic bird kill at a newly created wind farm would be disastrous from a public relations standpoint . At a time when most dyed-in-the-wool environmentalists are trying to find every reason to support wind power, the last thing we would wish upon the wind industry is a black eye.

Some proponents of Cape Wind claim that we have no time to lose and they invoke the overarching need to stem the production of greenhouse gases, because unless we do, “there will be no birds left to save.” This theory is compelling and all conservationists recognize the need to think globally; however, Mass Audubon’s particular mission is about protecting the nature of Massachusetts, and we would be remiss if we prescribed to a course of action that compromised that mission. At the very least, we owe it to the ecology of Nantucket Sound to take two more years to gather the data necessary to make an informed decision. Surely, the global climate won’t collapse between now and then.

Photograph credits

The views and opinions expressed in all articles that appear in "Conservation Perspectives" are those of the authors and do not necessarily reflect those of NESCB.