Regulatory

The Migratory Bird Treaty Act (MBTA) and the Bald and Golden Eagle Protection Act (BGEPA) provide legal mandates to protect birds.  Any activity, intentional or unintentional, resulting in take of migratory birds, including eagles, is prohibited unless otherwise permitted by the U.S. Fish and Wildlife Service (50 C.F.R. Sec. 10.12 and 16 U.S.C. Sec. 668(a)).  It is the responsibility of the Project proponent to comply with the MBTA and the BGEPA, and to seek appropriate guidance from the USFWS regarding conservation measures that avoid taking migratory birds and eagles.

The Fish and Wildlife Conservation Act (16 U.S.C. 2901–2912) (FWCA) directs the USFWS to identify Birds of Conservation Concern (BCC)—species, subspecies, and populations of migratory nongame birds that, without additional conservation actions, are likely to become candidates for listing under the ESA; recognizing that proactive bird conservation is critical at a time when continued human impacts will be intensified by effects of a changing climate.

Executive Order 13186: Responsibilities of Federal Agencies to Protect Migratory Birds protects migratory birds and migratory bird habitat. EO 13186 obligates all Federal agencies that engage in or authorize activities that might affect migratory birds, to minimize those effects and encourage conservation measures that will improve bird populations.

Baseline Conditions

The proposed Project area encompasses a total of 1009.4 acres, comprising a variety of habitat types as discussed in Sections 3.5 Vegetation and 3.6 Wildlife.  Because of the habitat diversity (upland forests, scrub, herbaceous, and wetlands), surrounding areas of undeveloped and relatively undeveloped rural land cover, the Project area provides significant high-quality habitat for nesting, foraging, and migratory stopovers for numerous bird species. 

Field investigations to identify bird habitat and birds that occur in the proposed Project area were conducted on October 3 and 4, 2023, and January 6 and 8, 2024.  The author, a wildlife biologist and avid birdwatcher, resides within one-half mile of the proposed Project site and has been making observations of birds in the area for nearly two years, as of this writing.  Of the 214 species observed in San Miguel County in 2023 (Cornell, 2023), 137 species have either been observed in or within close proximity to the proposed Project area, or due to habitat suitability, have a high probability of occurring within the Project area.  A complete list of species that were either observed in the Project area or have potential to occur in the Project area is provided in Appendix C.

A large raptor nest was observed in a ponderosa pine in the east array area.  The nest tree is located in an area of the east array that would be cleared for installation of the solar panels.  The nest tree is approximately 1/3-mile from the nearest residence.  A survey would need to be done during nesting season to determine to which species the nest belongs, but given the high numbers of red-tailed hawks in the area, the nest is most likely that of a red-tailed hawk.  CPW restrictions for activity around a red-tailed hawk nest are: no surface occupancy (beyond that which historically occurred in the area) within ⅓-mile radius of active nests. No permitted, authorized, or human encroachment activities within ⅓-mile radius of active nests from February 15 through July 15. Some individuals of this species have adapted to urbanization and may exhibit a high tolerance to human habitation and activities within 100 yards of their nest. Development that encroaches on rural nest sites is more likely to cause abandonment (CPW 2020).  The nest is within an undeveloped area away from residences and high-human activity.  Red-tailed hawks and their nests are protected by the MBTA and by CRS Title 33 – Parks and Wildlife.

Birds of Conservation Concern—migratory and non-migratory bird species that represent the USFWS highest conservation priorities (beyond those already designated as federally threatened or endangered) (USFWS, 2021).  The USFWS IPaC program has identified 15 BCC with potential to occur in the proposed Project area.  (The IPaC report is provided in Appendix E.)  Of those, seven species have been observed in the Project area.

Consequences

Construction of the Project would result in clearing and permanent loss of 580 acres of pinyon-juniper sagebrush scrublands, fragmenting habitat in the area and irrevocably impacting 1009.4 acres of foraging, breeding, migration habitat that supports over 137 species protected under the MBTA.  The Project would fragment habitat within the landscape of Wright’s Mesa, reducing the overall habitat quality in the area surrounding the proposed Project, and create more edge habitat which would change the habitat suitability for species that currently occur in areas surrounding the Project site.  The Project would also reduce the total available habitat for birds during migration between wintering areas and breeding grounds, an issue that’s becoming more critical as landscapes across the country and within the western hemisphere are under continued pressure for development.  Clearing of habitat during breeding season would result in the direct take of nests, eggs, sub-adult birds and cause increased stress and mortality on adult birds.  Clearing would also take the raptor nest tree discussed above.  The proposed Project would result in direct and indirect long-term adverse impacts to migratory birds.

Table 3-3. Birds of Conservation Concern, Potential for Occurrence in Project Area

The construction and operation of a solar facility and its associated ancillary facilities can directly cause bird fatality or sublethal effects (i.e., injury or energetic costs), the latter of which may lead to fatality or the individual not contributing to the population (e.g., inability to reproduce). One of the primary forms of mortality from solar facilities occurs when birds collide with project infrastructure, including security fences, collector and generation tie lines, PV panels.  (Agha et. al., 2020; Multiagency Avian-Solar Collaborative Working Group (ASWG), 2016). Impact trauma has been indicated as the leading cause of death documented at a PV facility in California; species affected ranged from hummingbirds to pelicans; from aerial feeders (swallows) to aquatic feeders (grebes) to ground feeders (roadrunners) to raptors (hawks and owls). The species identified were equally divided among resident and non-resident species, and nocturnal as well as diurnal species were represented. (Kagan et al., 2014).  Walston et al. (2016) estimated that the annual utility-scale solar energy-related avian mortality to be between 37,800 and 138,600 birds for all utility-scale solar energy facilities across the U.S. that are either installed or under construction. 

Glare from panels and mirrors, unexpected fluctuations in lighting, increased illumination, and night lighting could disorient birds or attract them to solar facilities (ASWG, 2016; BLM and DOE 2010, 2012; Hockin et al. 1992; Longcore et al. 2008; Navara and Nelson 2007; Longcore and Rich 2004); Light reflecting off panels may attract insects and insectivorous bird species (Harrison et al., 2016; Kagan et al. 2014; Horváth et al. 2009, 2010; Longcore and Rich 2004); • (ASWG, 2016)) leading to higher rates of mortality from collisions and adverse effects to local avian populations.  It has also been documented that large solar arrays create a “lake affect”, whereby the array of panels appears to birds as water.  The lake affect attracts birds and also insects that in turn attract birds.  Birds (especially waterfowl) mistaking the array for a body of water, attempt to land and are injured and killed on impact. (Kagan et al. 2014; Smith and Dwyer, 2016; ABC, 2015).  The proposed Project would create the lake affect.  The layout of the east array would leave the riparian corridor along the Gurley Ditch and remaining wetland areas as habitat “islands” within the lake affect.  Because of the incidence of bird mortalities from solar arrays, the American Bird Conservancy (ABC) specifically states that large arrays should not be placed near populations of rare or endangered species, in major migratory routes, near wetlands or close to active agricultural lands (ABC, 2015).

Wetland habitats in the shale deserts and sedimentary basins of the Colorado Plateau ecoregion provide essential habitat value for resident and migrating birds, and are of particular importance for breeding, resting and refueling along migration routes. With increased stress due to habitat loss, pollution, climate change, and invasive species, many bird species are declining, making conservation of wetland habitat essential to sustain bird populations (USFWS, 2021).  Solar arrays also increase evaporation and evapotranspiration which would likely change the plant communities in these areas over the course of the project life, adversely impacting wetland habitats and birds that use those areas. 

No Action Alternative

The No Action Alternative would result in no impacts to the migratory birds.