Northern Colorado Area Plan 230kV Transmission/Substation Project. Appendix D 2017 Biological Resources Report

Transcription

1 Northern Colorado Area Plan 230kV Transmission/Substation Project Appendix D 2017 Biological Resources Report

2 December 14, 2017 Erin Degutis Xcel Energy Senior Agent, Siting and Land Rights 1800 Larimer Street, 4 th Floor Denver, CO Subject: Biological Survey Results Dear Erin, Introduction and Purpose Two Logan Simpson biologists (team) conducted a biological reconnaissance survey of the WAPA Ault Substation to Husky Substation alternative routes on December 7, 2017 from 9:00 to 13:30. The purpose of the survey was to provide data to inform siting decisions and to satisfy NEPA requirements for this phase of the proposed project. The focus of the survey was to identify historic raptor nests, record wildlife observations, and provide field confirmation of wetland areas previously identified with desktop analysis and National Wetland Inventory (NWI) data. In addition, the team recorded several infrastructure observations for possible consideration in siting decisions. Methods Surveys were primarily conducted from the vehicle on public roads or private roads for which the landowner had granted access permission. In one wetland area (described in detail below), the team walked around an accessible part of the wetland to improve observation. The survey area was generally within 0.5 mile of the alternative centerlines, as access and observation points permitted. A 0.5 mile distance was selected to include habitat within the construction exclusion zone for raptor species with potential to nest in the area. Maps of the survey area were plotted on high resolution aerials, saved as GIS background files, and loaded onto a Trimble Juno GPS unit for navigation and data collection purposes. Nikon Monarch 10.5 X 45 binoculars and a Leupold 20 X 60 spotting scope were used for visual observations. Photographs were taken with a cell phone and a Canon 20X zoom camera to document observations.

3 Results The survey area consists of highly fragmented rural and agricultural land. Scattered structures including residences, farm buildings, fences, silos, center pivot, and other irrigation systems are present throughout. Both small and large irrigation canals traverse the survey area. Large trees in the area are typically associated with human habitation, located along roads and near homes and farms. Other existing infrastructure in the survey area includes paved roads, non-paved roads, transmission systems, oil and gas wells, storage tanks, pipelines, and water wells. The U.S. Fish and Wildlife Service National Wetlands Inventory (NWI) dataset identifies five features within the survey area. These features include: 2 Riverines 1 Freshwater Forested / Shrub Wetland 1 Freshwater Emergent Wetland 1 Freshwater Pond After observing these features in the field it was determined that the two NWI riverines are human constructed irrigation canals used for agricultural purposes (dry at time of survey). The freshwater pond (NWI-1) and freshwater emergent wetland (NWI-2) are connected as part of the same constructed pond area which at one time pulled water from the adjacent irrigation canal. The pond area, which has a constructed dam on the eastern edge, was dry at the time of survey but had signs of recent saturation (possibly from the spring season). Vegetation in the western portion of the area near the canal (NWI freshwater emergent wetland) was dominated by plains cottonwood (Populus deltoids), willows (Salix sp.), cattails (Typha sp.) and tall unidentified grasses. Vegetation in the eastern portion of the area towards the dam (NWI freshwater pond) primarily consisted of tall grasses. The NWI classified freshwater forested / shrub wetland located northwest of the irrigation canal and constructed pond area contained two distinct depressions (Photographs 6 and 7) that were dry at the time of visit but showed signs of standing water earlier in the year. Vegetation on this site was not easily identifiable but did contain sedges (Carex sp.) which are commonly associated with wetland areas. Additionally, two potential wetlands not included in the NWI dataset were identified within the survey area. The first (WF-1) is located adjacent to the eastern irrigation canal on private property near a residence (Photograph 1). Vegetation on this site consisted of plains cottonwood, willows and tall unidentified grasses. The second (WF-2) is located south of CR 86

4 on a parcel owned by the City of Thornton and contained standing water at the time of the field survey (Photograph 2). Although a formal delineation was not completed, the wetland features are small enough to make avoidance of any disturbance realistic through careful structure placement. Avoidance of direct disturbance would eliminate the need for obtaining a Section 404 permit and associated mitigation requirements. Vegetation in the survey area primarily consisted of cultivated agricultural land and pastures. Ornamental trees and shrubs were present around homes and buildings. A total of five wetland or potential wetland areas were documented during the survey. Table 1 and Figure 1 present these features. Table 1 Wetland and Potential Wetland Features in the Survey Area Feature Location Area 1 Potential wetland area (WF-1) , acres Potential wetland area (WF-2) , acres Dry pond area (NWI-1) , acres Potential wetland area (NWI-2) , acres Potential wetland area (NWI-3) , acres 1 Area was determined in GIS using aerial imagery and is approximate

5 Figure 1 General Overview of Observed Potential Weltand Areas in Survey Project Area Figure 2 General Overview of Observed Raptor Nests in Project Area

6 In addition to wetland areas, two wooded areas with good potential wildlife habitat were documented. These areas were associated with water, including proximity to canals. Woody vegetation with structural variety would be expected to attract a greater diversity of wildlife species. A total of eight mule deer (Odocoileus hemionus) were observed in the western portion of the wetland area (NWI-2). It is suspected that this small herd is fairly isolated at this location. No connectivity habitat was apparent and the landowner immediately north of the wetland area maintained a deer hunting blind and other hunting equipment adjacent to the wetland area. A variety of raptor and other avian species inhabits the vegetative communities in the survey area. Suitable nesting, foraging, migration, and winter habitat exists throughout. Table 2 presents raptor and representative migratory bird species with potential to occur in the survey area at some point in their annual life cycle. This survey was conducted outside the breeding and migration season for avian species in northern Colorado. It was expected that many avian species that could occur in the survey area would not be observed during this time. However, it was advantageous to be able to identify stick nests in trees after leaf drop. Table 2 Raptor and Migratory Bird Species with Potential to Occur in the Survey Area Common Name Scientific Name Nesting Habitat Season of Use Raptor Species American kestrel Falco sparverius Cavities in trees and human-made structures Year-round Barn owl Tyto alba Variety of habitats including old buildings and burrows in walls of dry washes Year-round Burrowing owl Athene cunicularia Mammalian burrows Breeding season Cooper s hawk Accipiter cooperi Stick nest in trees Year-round Eastern screech-owl Megascops asio Tree cavities Breeding season Ferruginous hawk Buteo regalis Stick nest in trees, on rock outcrops Year-round Great horned owl Bubo virginianus Variety of habitats including trees and on human-made structures Year-round Long-eared owl Asio otus Edge habitat in tree stands or dense shrubs Year-round Northern harrier Circus cyaneus Ground nest in grassland and agricultural land Year-round Northern rough-legged hawk Buteo lagopus Breeds elsewhere Winter Red-tailed hawk Buteo jamaicensis Stick nest in trees Year-round Short-eared owl Asio flammeus Nests on the ground in grassland and agricultural land Year-round Swainson s hawk Buteo swainsoni Nests in trees in grassland and agricultural land Breeding season Representative Non-raptor Species American tree sparrow Spizella arborea Breeds elsewhere Winter Barn swallow Hirundo rustica Mud nest on human-made structures Breeding season Black-billed magpie Pica hudsonia Stick nest in trees and shrubs Year-round Canada goose Branta canadensis Ground nest near water bodies Year-round Eurasian collared-dove Streptopelia decaocto Small stick nest in trees Year-round Horned lark Eremophila alpestris Ground nest in grassland and agricultural land Year-round Killdeer Charadrius vociferus Ground nest in variety of habitats Breeding season Lark sparrow Chondestes grammacus Ground nest in variety of habitats Breeding season

7 Table 2 Raptor and Migratory Bird Species with Potential to Occur in the Survey Area Common Name Scientific Name Nesting Habitat Season of Use Northern flicker Colaptes auratus Cavity nest in trees Year-round Red-winged blackbird Agelaius phoeniceus Wetland and cattail habitat Year-round Western kingbird Tyrannus verticalis Trees in a variety of habitat types Breeding season Western meadowlark Sturnella neglecta Shrubs in grassland and agricultural land Year-round A total of four stick nests were documented in the survey area (Table 3 and Figure 2). It was not possible to identify which species used the nest in 2017, if any. It is common for raptor nests to be used by different species, including non-raptors, in different years. For example, most owls do not construct their own nests; they use previously constructed nests or burrows. No owl or eagle species were observed during the survey; however, anecdotal reports were provided by a landowner that indicated presence of a barn owl on the property and a bald eagle observed flying over the property. Raptor species typically exhibit high fidelity to nests and nesting territories. For this reason, it is useful to identify historic raptor nests even while they are not active. New raptor nests can be constructed each year and historic nests may go unused. In order to comply with the Migratory Bird Treaty Act pre-construction nest surveys for raptors and other avian species would be conducted no sooner than one week prior to disturbance. Timing and distance buffers that are appropriate for the species would be applied to any active nests. If any nests are observed during the pre-construction nest survey, monitoring by a qualified avian biologist would be conducted until the nest fledges. Pre-construction nest surveys and monitoring would be coordinated with Colorado Parks and Wildlife and the U.S. Fish and Wildlife Service. These agencies are responsible for protection of raptor and other avian species and have the authority to establish or adjust timing and distance stipulations according to conditions in the field. Raptor sensitivity to noise and human disturbance varies by species and individual. Table 3 Historic Raptor Nests in the Survey Area Nest Location Distance from Centerline N , feet N , miles N , miles N , feet A total of nine avian species were observed during the survey: 1 male American kestrel, 10 American tree sparrows, 2 black-billed magpies, 500 Canada geese (appx.), 2 Eurasian collared-

8 doves, 40 horned larks (appx.), 3 female northern harriers, 50 red-winged blackbirds (appx.), 6 red-tailed hawks, and 2 western meadowlarks. One small active black-tailed prairie dog (Cynomys ludovicianus) colony was documented, which could serve as nesting habitat for burrowing owl. In addition, prairie dogs are an important prey species for raptors and other predators. This colony was located at N, W (PC-1, Figure 3), and was approximately 3 acres in size. Figure 3 General Location of Prairie Dog Colony in Project Area Respectfully submitted, Julie Capp Certified Wildlife Biologist Certified Audubon Master Birder Logan Simpson David Casey Balthrop Biologist Logan Simpson

9 Attachment A: Representative Photographs Photograph 1 View of Potential Wetland Feature (WF-1) ( , )

10 Photograph 2 View of Potential Wetland Feature (WF-2) ( , ) Photograph 3 View of Dry Pond Area (NWI-1) ( , )

11 Photograph 4 View of Potential Wetland Feature (NWI-2) ( , )

12 Photograph 5 Panoramic View of Dry Pond Area (NWI-1) and Potential Wetland Feature (NWI-2) Photograph 6 First Depression in Potential Wetland Area (NWI-3) ( , )

13 Photograph 7 Second Depression in Potential Wetland Area (NWI-3) ( , ) Photograph 8 View of Raptor Nest (N-2) (Species Unknown) ( , )

14 Photograph 9 View of Raptor Nest (N-4) (Species Unknown) ( , ) Photograph 10 Red-tailed Hawk Perched on Tree in Survey Area ( , )

15 Photograph 11 View of Black-tailed Prairie Dog Colony in Project Area (approximately 3 acres) ( , ) Photograph 12 Fire Hydrant approximately 1 mile west of existing WAPA Ault Substation on CR25 ( , ) (potential indication of future housing development)