Wind power is increasingly recognized as an accessible, carbon-emission-free energy source, which can help meet growing energy requirements while mitigating the environmental impacts of fossil fuel-based energy generation (Allison et al. 2008, Snyder and Kaiser 2009, American Wind Energy Association [AWEA] 2010). Mounting interest in wind power has recently made it competitive with other power sources (Kuvlesky et al. 2007), and it is now one of the fastest-growing segments of the electricity market in several countries, including the United States (Stewart et al. 2007, Snyder and Kaiser 2009). Despite these advantages, the rapid expansion of wind development has led to concerns over its detrimental impacts on birds, including mortality from turbine collisions, blocking of flight pathways, and alteration of habitats (Drewitt and Langston 2006). In the United States, regulatory agencies are tasked with evaluating and mitigating threats to bird populations on public lands, under laws such as the Migratory Bird Treaty Act and the Endangered Species Act (Allison et al. 2008). This responsibility also pertains to waters within the U.S. Atlantic Outer Continental Shelf (OCS) zone, where construction of numerous wind facilities is planned (O’Connell et al. 2009).
Some studies have evaluated the effects of offshore wind facilities on marine birds in Europe, where over 900 turbines (located > 5.6 km off the coastlines of eight different countries) have begun operating in the last 15 years, and several thousand more are planned or under construction (Desholm and Kahlert 2005, Allison et al. 2008, EWEA 2011). Findings have varied greatly by location, species, and study design (Drewitt and Langston 2006, Stewart et al. 2007). Thus, the extent of risk that birds face from offshore wind development remains unclear, particularly in the U.S., where no turbines have been constructed in the marine environment (Allison et al. 2008, AWEA 2010). As a first step in evaluating the frequency of such interactions and the potential risks posed by them, there is a need to collect information on the distribution and behavior (e.g., flight heights, direction, timing) of birds occurring in offshore areas where wind facilities may be sited (Richardson 2000, Allison et al. 2008, O’Connell 2009). This information can be used to generate models to predict impacts of future offshore wind turbines, serve as a baseline for comparisons with post-construction species monitoring efforts, and identify subsequent research and conservation priorities for species that may be most affected by offshore wind development (Drewitt and Langston 2006, O’Connell et al. 2009, Burger et al. 2010). While birds with largely offshore ranges, including seabirds and marine waterfowl, are thought to have the greatest chance of interacting with offshore wind facilities (Allison et al. 2008, Desholm 2009), there is also a need to examine interactions between offshore wind development and other avian taxa that regularly utilize marine environment, such as shorebirds.
“Shorebirds” are comprised of two closely-related clades within the avian order Charadriiformes (Patton and Baker 2006, Baker et al. 2007). These clades include the suborders Scolopaci (sandpipers, phalaropes and allies) and Charadrii (avocets, stilts, oystercatchers, and plovers), as well as two others (Thinocori, Chionidi) not found in North America (Hayman et al. 1986, Patton and Baker 2006, Baker et al. 2007). Many shorebird species use coastal and near-coastal habitats during substantial portions of their lifecycles (Hayman et al. 1986). While few studies have examined shorebird use of offshore and marine environments (Burger et al. 2010), their extensive distribution in near-coastal waters, and highly migratory behavior, including multiple reports of over-ocean flights (Hayman et al. 1986, Poole 2010), suggest shorebirds could be exposed to offshore wind facilities, increasing their risk of disturbance and mortality.
Here we review existing occurrence information, movement patterns, and flight behavior for shorebirds in the OCS zone. Our report is associated with the Compendium of Avian Occurrence Information for the Continental Shelf Waters Along the Atlantic Coast of the United States (hereafter “Offshore Atlantic Bird Compendium”), which addressed seabird occurrence (O’Connell et al. 2009).