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HomeMy WebLinkAbout2.0 04.11 Raptor Survey ReportHIGH MESA 16-INCH DISCHARGE PIPELINE Raptor Survey Report Garfield County, Colorado Cover: Representative view of suitable raptor nesting habitat in the project area. Prepared for: EnCana Oil & Gas (USA) Inc. Prepared by: WestWater Engineering 2516 Foresight Circle #1 Grand Junction, CO 81505 Apri12011 1.0 INTRODUCTION 1.1 Project Description At the request ofEnCana Oil & Gas (USA) Inc. (EnCana), WestWater Engineering (WWE) conducted a raptor survey update for the proposed High Mesa I 6-inch discharge pipeline. The proposed alignment is located in Sections 35 and 36 T7S R96W and Sections 2 and 3 T8S R96W, 6th Principal Meridian. This area is located south of the Colorado River between the towns of Parachute and De Beque, Colorado (Figurel- inset). The proposed alignment generally follows an existing pipeline corridor between Wallace Creek Road (Garfield County Road 306) and a compressor station on the western edge of High Mesa. Access to the project area is currently available via Stone Quarry Road (Garfield County Rd. 300) from U.S. Highway 6. The current primary uses of the area surrounding the proposed alignment are rural residential sites, pasture and rangeland, wildlife habitat, and natural resource extraction including natural gas development. 1.2 General Survey Information Information used in the preparation of this report was gathered by WWE biologists during 20 II field surveys and previous raptor surveys and observations within the general area of the proposed pipeline. Raptor survey boundaries evaluated for this report are shown in Figure I. The purpose of the surveys was to identify raptor nest locations and occupancy status within the project area and that could potentially be impacted by project development. This report provides written documentation that describes survey findings as well as recommended mitigation measures. 2.0 LANDSCAPE SETTING 2.1 Vegetation and climate Natural vegetation communities around the project area have been affected by residential development, agriculture, fire, livestock grazing, and natural gas developments. Native vegetation in the project area consists of pinyon-juniper woodlands (Pinus edulis and Juniperus osteosperma) accompanied by big sagebrush (Artemisia tridentata), Gambel oak (Quercus gambelii), and serviceberry (Amalanchier alnifolia). Other common native plants include broom snakeweed (Gutierrezia sarothrae), Fremont cottonwood (Populusfremontii), Indian ricegrass (Achnatherum hymenoides), kingcup cactus (Echinocereus triglochidiatus), narrowleaf cottonwood (Populus angustifolia), prickly pear cactus (Opuntia spp.), yucca (Spanish bayonnet) (Yucca harrimaniae), three- leaf sumac (Rhus trilobata), wavyleafthistle (Cirsium undulatum), and yellow rabbitbrush (Chrysothamnus viscidiflorus). Common non-native plants included dryland alfalfa (Medicago sativa), prickly lettuce (Lactuca serriola), yellow salsify (Tragopogon dubius), yellow sweet-clover (Melilotus officina/is), and several introduced grasses including downy brome (Bromus tecto rum). The climate for the Colorado River Valley in the project area is considered semi-arid with a wide range of annual temperatures and precipitation. The average annual precipitation WestWater Engineering Page I of9 April2011 in the region ranges between 12 and 15 inches, and temperatures range from about 95 degrees F in the summer months to -10 degrees F during the winter months. 2.2 Terrain The project area lies south of the Colorado River near Una on U.S. Highway 6. Terrain at the site is moderately sloping to the Colorado River. The proposed alignment is crossed by three named streams (Wallace Creek, Spring Creek, and Pete and Bill Creek) and several unnamed drainages that flow to the north. The proposed alignment terminates on the western edge of High Mesa. Elevation at the site varies from approximately 5,225 feet above sea level at Wallace Creek, to approximately 6,250 feet above sea level on High Mesa. 3.0 RAPTOR SURVEYS 3.1 Background Information and Survey Methods A list of Birds of Conservation Concern (BCC) published by the USFWS through a Memorandum of Understanding with the Bureau of Land Management (BLM) and the U.S. Forest Service (USFS) was reviewed (USFWS 2008). Western Colorado is included in Bird Conservation Region (BCR) 16 as mapped by the USFWS. Several BCC raptor species included in the list for Region 16 occur regularly in Colorado, although some are present only as seasonal migrants. Avian literature sources such as the "Birds of Western Colorado Plateau and Mesa Country" (Righter et al. 2004) and the "Colorado Breeding Bird Atlas" (Kingery 1998) were reviewed to determine the likelihood for species occurrence within the project area. Bird identification and taxonomic nomenclature are in accordance with that applied by the Colorado Breeding Bird Atlas Project (Kingery 1998). A preliminary review of the project area, using aerial photographs, was conducted to familiarize personnel with vegetation types and terrain and as an aid to help determine potential raptor nesting habitat. Field data, including general project location, boundaries, and reported features, were verified and/or recorded with the aid of a handheld global positioning system (GPS) receiver utilizing NAD83 map datum, with all coordinate locations based on the Universal Transverse Mercator (UTM) coordinate system within Zone 12. Pedestrian surveys were conducted April 18, 20, and 21, 2011 to identify and locate raptor nests. Visual searches for raptor and other bird species nests were focused on the pinyon-juniper woodlands and riparian areas within the survey area. In addition to a visual search for tree nests, Great Homed Owl calls were broadcast at approximately 200 meter intervals throughout the survey area using FoxPro® NX3 wildlife calls. This call- playback methodology has been shown to elicit a response from nesting raptors in the area, particularly members of the Genera Accipiter and Buteo (Kennedy and Stahlecker 1993; Reynolds et.al. 1992). Nest searches and bird identification were aided with the use of binoculars and call recognition, where needed. WestWater Engineering Page 2 of9 April2011 4.0 RESULTS OF SURVEY 4.1 Raptors Several raptor species nest, reside, forage, or pass through the general area of the proposed pipeline and are included in Table I. Five of these species are included on the Federal BCC list. American Falco Coniferous and deciduous forests and open Kestrel sparverius N terrain with suitable perches. Nests in cavities in trees, cliffs and buildings. American Falco High cliffs near pinyon-juniper, ponderosa, or Peregrine peregrines y spruce-fir forests. Elevations from 4,500 to Falcon annatum over 9,000 ft. Nest in mature cottonwoods or large pines Haliaeetus usually near large rivers or other bod1es of Bald Eagle leucocephalu y water. Winters m a variety of habitats and may be far from water feeding on carrion s from road or winter kills. Elevation 4,400 to 8,500 ft. for nesting. Cooper's Accipiter Cottonwood riparian to spruce/fir forests, Hawk cooperii N including pifiollljuniper woodlands. Nests most frequently m pmes and Grasslands, shrub lands, agricultural areas, Golden Eagle Aquila y pifion-juniper woodlands, and Ronderosa chrysaetos forests. Prefers nest sites on c iffs and sometimes in trees in rugged areas. Great Horned Bubo Occupies diverse Owl virginianus N deciduous and adjacent open Flammulated Otus jlameolus y montane evergreen forests with available Owl cavities. Elevations 6,000 to I 0,000 ft. Long-eared Occupies mixed shrublands. Nests and roost Asio otus N in sites in dense cottonwoods, willows, scrub Owl oak, ;,unipers and dense forest of mixed coni ers and aspens. Grassland, shrubland, agricultural areas, and Northern marshes. Nests in areas with abundant cover Harrier Circus cyaneus N ( eJ, tall reeds, cattails, grasses) in grasslands an marshes. Also known to nest in high- elevation sagebrush. Glaucidium Nests in tree cavitites in open coniferous Northern woodlands in a broad elevation ran8e. Pygmy Owl gnoma N Requires open areas for hunting an does not occufJy large expanses of continuous woo lands. West Water Engineering Page 3 of9 April2011 Northern Saw-Aegolius Nests in tree cavities in all types of forests, whet Owl acadicus N includin,g pinyon-juniper woodands. May also utilize man-made nest boxes. Nest on cliffs near open habitats such as Falco grasslands and shrub lands. Year-round Prairie Falcon mexicanus y resident of Colorado. Elevation generally below 10,000 feet, but occasionally above timberline. Diverse habitats including ~asslands, Jlifion- Red-tailed Buteo juniper woodlands and dectduous, comferous Hawk jamaicensis N and riparian forests. Nests in mature trees (especially cottonwood, aspen, and pines) and on cliffs and utility poles. Sharp-shinned High densi7c young, or even-aged, stands of Accipiter N coniferous orest and deciduous forests of Hawk striatus aspen or oak brush with small stands of conifers. Swainson's Buteo N Arid grassland, desert, and aficultural areas Hawk swainsoni with scattered trees and shru s. Western Otus Nests in cavities in deciduous trees in rrearian Screech Owl kennecottii N corridors, and open conifer forests to a esser extent. Results: No occupied raptor nests were observed in the approximately 712 acres of raptor nesting habitat that was surveyed. Two raptor nests discovered in 20 I 0 were revisited to determine their 2011 occupancy status; neither nest was occupied. Six additional unoccupied potential raptor nests were located during the survey. These nests are similar in shape and size to nests built by Accipiters (Cooper's Hawk and Sharp- shinned Hawk), but are difficult to distinguish from nests built by Corvids (specifically Common Raven and American Crow). Common Ravens were observed nesting within the survey area. Nest locations are available in Table 2. UNHA-1 12 751528 4364402 UNHA No sign of occupancy in 20 II. or Corvid nest. UNHA-2 12 751587 4363174 UNHA No sign of occupancy in 20 II. or Corvid nest. UNHA-3 12 752292 4364009 UNHA No sign of occupancy in 2011. or Corvid nest. UNHA-4 12 752635 4364444 UNHA No occupancy 2011. or Corvid nest. WestWater Engineering Page 4 of9 April2011 UNHA-5 12 752944 4364130 UNHA UNHA-6 12 753269 4364295 UNHA UNHA-7 12 753374 4364101 UNHA * COHA~ Cooper's Hawk; UNHA~Unknown Hawk Species American Kestrel, Cooper's Hawk, and Red-tailed Hawk were observed in several locations along the proposed alignment. Based on behavioral observations of these individuals, it is unlikely that the birds observed are nesting within the survey area. 4.2 Birds of Conservation Concern (BCC) other than rap tors In addition to the raptors discussed above, WWE biologists documented the presence of BCC (songbirds) and their habitat. BCC habitat and nesting records, as described in the Colorado Breeding Bird Atlas (Kingery 1998), Colorado Birds (Andrews and Righter 1992), and Birds of Western Colorado Plateau and Mesa Country (Righter eta!. 2004) in the vicinity of the project area are summarized in Table 3. Results: Juniper Titmouse and Pinyon Jays were observed in pinyon-juniper woodlands between Wallace and Spring Creeks and on High Mesa. No nests were discovered. There is adequate sagebrush habitat for Brewer's Sparrows in the project area but none were observed. In addition to raptors and BCC, the following bird species were observed in or near the project area: American Robin (Turdus migratorius), Blue-gray Gnatcatcher (Polioptila caerulea), Chipping Sparrow (Spizella passerina), Common Raven (Corvus corax), Mourning Dove (Zenaida macroura), Plumbeous Vireo (Vireo plumbeus), Red-winged Blackbird (Agelaius phoeniceus), Rock Wren (Salpinctes obsoletus), Spotted Towhee (Pipilo maculatus), and White-breasted Nuthatch (Sitta carolinensis). 5.0 EFFECTS TO WILDLIFE 5.1 Wildlife Impact Assessment Construction of the pipeline will affect on-site native vegetation and wildlife habitat, although much of the proposed alignment lies within or adjacent to an existing pipeline corridor that has been previously disturbed and reclaimed. Locating the pipeline within and adjacent to an existing pipeline lessens the potential effects to wildlife. The primary WestWater Engineering Page 5 of9 April2011 effects would be habitat alteration and displacement of individuals through disturbances related to increased development. 5.1.1 Birds Raptors: o raptor nests are in danger of direct removal. At the time of the raptor survey no occupied raptor nests were discovered, and therefore there would be no expected effects to nesting raptors from the project construction. If construction is delayed it is possible that raptors may still select nest sites within the project area survey boundaries. These newly established raptor nests may be affected by disturbance associated with the proposed project and if project completion is delayed, the area should be resurveyed by qualified biologists. Passerine Species: The affects to foraging and nesting habitat to a small number of bird species is expected to be minimal. Vegetation that will be removed from the site is not unique and loss of habitat will not affect overall passerine populations. 6.0 MITIGATION RECOMMENDATIONS The following recommendations for mitigation are presented for maintenance and improvement of wildlife habitat, quality, and prevention of human-caused impacts to resources. 6.1 Maintenance and Restoration of Habitat Reclamation plans should include efforts to restore the native vegetation communities once construction is complete in the project area. Reclamation recommendations are found in the "Integrated Vegetation and Noxious Weed Management Plan (IVNWMP), High Mesa 16-Inch Discharge Pipeline" (WWE 201 0) which contains a recommended seed mixture for reclamation of the disturbed areas. If properly applied, this seed mixture will benefit all wildlife populations in the area . The IVNWMP also recommends ongoing control of noxious weeds which will aid the establishment of desired vegetation in the reclaimed area benefiting all wildlife species in the area. 6.2 Planning for Sensitive Time Periods and Areas 6.2.1 Raptors Pipeline construction activities within the project area are unlikely to affect rap tor population . If construction is delayed the area should be resurveyed to ensure no new raptor nests have been built that may be affected by the project. If occupied nests are then discovered, the potential for possible effects to raptors could be reduced by scheduling construction activities so there is no interference with breeding, nesting, and brood rearing activities of the species occupying the new nest sites. If occupied nests are discovered during subsequent surveys, WWE recommends temporal and spatial restriction guidelines for construction activities near active nests based on BLM stipulations (BLM 1987), Colorado Division of Wildlife (CDOW) recommendations (Craig 2002 and Klute 2008) and literature review of nesting season timing for raptors in the Roan Plateau region (Andrews and Righter 1992, Kingery 1998). These recommendations are summarized in Table 4 . WestWater Engineering Page 6 of9 April2011 *Great 6.2.2 Migratory Birds In order to comply with the Migratory Bird Treaty Act by showing a good faith effort to reduce potential impacts on nesting birds, any brush/tree clearing at the project site should take place outside of the nesting season. Nesting season for migratory birds is generally considered to occur between May 15 and July 31 in this area for most species. June I to July 15 is the peak period when most incubation and brood rearing takes place. If brush/tree clearing can occur prior to nesting, most affected birds will relocate to alternate nesting sites. After mid-to-late July, most fledging has occurred and brush/tree clearing impacts would be minimized. WestWater Engineering Page 7 of9 April2011 season. 7.0 REFERENCES Andrews, R., and R. Righter. 1992. Colorado Birds: A Reference to Their Distribution and Habitat. Denver Museum of Natural History, Colorado. BLM. 1987. Grand Junction Resource Area Resource Management Plan and Record of Decision. Bureau of Land Management, Department of the Interior, Grand Junction. Craig, Gerald R. 2002. Recommended Buffer Zones and Seasonal Restrictions for Colorado Raptors. Colorado Division of Wildlife, Denver. Kennedy, P. L., and D. W. Stahlecker.l993. Responsiveness of nesting northern goshawks to taped broadcasts of3 conspecific calls. Journal of Wildlife Management, 57:249-257. Kingery, H. E. 1998. Colorado Breeding Bird Atlas. Colorado Bird Atlas Partnership, Colorado Division of Wildlife, Denver. Klute, D. 2008. Recommended Buffer Zones and Seasonal Restrictions for Colorado Raptors. Colorado Division of Wildlife, Denver. Reynolds, R. T., R. T. Graham, M. H. Reiser, R. L. Bassett, P. L. Kennedy, D. A. Boyce Jr., G. Goodwin, R. Smith and E. L Fisher. 1992. Management recommendations for the northern goshawk in the southwestern United States. General Technical Report RM-GTR-217, U.S. Department of Agriculture, U.S. Forest Service, Rocky Mountain Forest and Range Experiment Station, Fort Collins, Colorado. Righter, R., R. Levad, C. Dexter, and K. Potter. 2004. Birds of Western Colorado Plateau and Mesa Country. Grand Valley Audubon Society, Grand Junction, Colorado. USFWS. 2008. Birds of Conservation Concern 2008. U.S. Fish and Wildlife Service, Division of Migratory Bird Management, Arlington, Virginia. WWE. 2010. WestWater Engineering. Integrated Vegetation and Noxious Weed Management Plan. High Mesa 16-inch Discharge Pipeline, Garfield County, Colorado. June, 2010. WestWater Engineering Page 8 of9 April2011 * Unoccupied Rap tor Nests -High Mesa 16" Discharge D 1/4 Mile Raptor Survey Buffer L]BLM High Mesa 16ia Discharge Pipeliae Biologkal Sarvey Locatio• aad Raptors .n '\Nest Water Engineering -:;;; Comulling Eng~rs & Scientist> 0 1,000 Feet April 2011 2,000 ...