A Comprehensive Analysis of Small-Passerine Fatalities from Collision with Turbines at Wind Energy Facilities

Abstract

Small passerines, sometimes referred to as perching birds or songbirds, are the most abundant bird group in the United States (US) and Canada, and the most common among bird fatalities caused by collision with turbines at wind energy facilities. We used data compiled from 116 studies conducted in the US and Canada to estimate the annual rate of small-bird fatalities. It was necessary for us to calculate estimates of small-bird fatality rates from reported all-bird rates for 30% of studies. The remaining 70% of studies provided data on small-bird fatalities. We then adjusted estimates to account for detection bias and loss of carcasses from scavenging. These studies represented about 15% of current operating capacity (megawatts [MW]) for all wind energy facilities in the US and Canada and provided information on 4,975 bird fatalities, of which we estimated 62.5% were small passerines comprising 156 species. For all wind energy facilities currently in operation, we estimated that about 134,000 to 230,000 small-passerine fatalities from collision with wind turbines occur annually, or 2.10 to 3.35 small birds/MW of installed capacity. When adjusted for species composition, this indicates that about 368,000 fatalities for all bird species are caused annually by collisions with wind turbines. Other human-related sources of bird deaths, (e.g., communication towers, buildings [including windows]), and domestic cats) have been estimated to kill millions to billions of birds each year. Compared to continent-wide population estimates, the cumulative mortality rate per year by species was highest for black-throated blue warbler and tree swallow; 0.043% of the entire population of each species was estimated to annually suffer mortality from collisions with turbines. For the eighteen species with the next highest values, this estimate ranged from 0.008% to 0.038%, much lower than rates attributed to collisions with communication towers (1.2% to 9.0% for top twenty species).

Boreal bird abundance estimates within different energy sector disturbances vary with point count radius

“…The direct effects of wind energy development on birds have received considerable attention (e.g., Smallwood and Thelander 2008, Loss et al 2013, Erickson et al 2014. Collisions between birds and onshore wind turbines result in impact trauma, which can result directly in death or render birds more susceptible to predation.…”

“…While the number of birds affected is uncertain (Pagel et al 2013), estimates adjusted for searcher detection and scavenger removal suggest that between 140,000 and 328,000 birds are killed annually by collisions with turbines at wind energy facilities in the contiguous U.S. (Loss et al 2013). For songbirds in particular, fatalities at wind energy facilities in the U.S. and Canada are estimated to be between 134,000 and 230,000 annually (Erickson et al 2014 Morinha et al 2014), suggesting that the direct effects of wind energy facilities are of concern globally. Intuitively, mortality rates at wind energy facilities should be related to avian abundance (Carrete et al 2012), but a more complex suite of site-specific factors may be important (De Lucas et al 2008, Marques et al 2014.…”

Comparing pre- versus postoperational movement of nocturnal migrants around a wind energy facility in northeast British Columbia, Canada

“…During the spring and fall periods, nocturnally migrating passerines are the most abundant avian group encountering wind energy facilities (Marques et al 2014), which is reflected in the high proportion of passerine carcasses that are typically found at wind projects (Johnson et al 2002, Zimmerling et al 2013, Erickson et al 2014. Passerines typically compose 80% of all fatalities at such installations, most of which involve nocturnal migrants (Mabee et al 2006, Kuvlesky et al 2007.…”

An autonomous GPS geofence alert system to curtail avian fatalities at wind farms

“…A growing literature is documenting the serious impacts that wind farms can have on resident and migratory avifauna populations through mortalities from direct collisions with turbines [2,3]. Recent estimates indicate that wind farms in North America are responsible for up to 368,000 bird fatalities annually [4]. Consequently, the development and implementation of effective measures to reduce wind energy impacts on wildlife is recognized as a top priority by biologists, conservation organizations, regulators and the private sector (see reviews by [5][6][7]).…”