HomeMy WebLinkAboutPoint Lay Wind Turbine Project Potential Environmental Effects on Wildlife Report - Oct 2007 - REF Grant 7040027109/214
POTENTIAL ENVIRONMENTAL EFFECTS ON WILDLIFE FROM THE
PROPOSED WINDFARM AT POINT LAY, ALASKA
Prepared for
Powercorp Alaska, LLC
Anchorage, AK
by
Betty A. Anderson
ABR, Inc.—Environmental Research & Services
P.O. Box 80410, Fairbanks, AK 99708–0410
15 October 2007
______________________________________________________________________________
INTRODUCTION
The North Slope Borough is proposing to build a small windfarm (3 wind turbines) near the
village of Point Lay on the northwestern coast of Alaska (69 45’N, 163 03’W). As part of the
preliminary review of this proposed windfarm, Powercorp Alaska, LLC, contracted with ABR to
evaluate the potential environmental effects on wildlife from the proposed wind turbines and
power lines required for the project. To accomplish this task, ABR reviewed the available litera-
ture and unpublished data available on wildlife resources in the Point Lay area to determine
those species most like to be effected by the proposed windfarm. Birds are the primary wildlife
group likely to be affected by a windfarm in northwestern Alaska, but populations of large
mammals (e.g., bears) that might occur in the vicinity of the windfarm could potentially be af-
fected by the windfarm construction and operations.
WILDLIFE POPULATIONS
MAMMALS
Point Lay area is located on the northwestern coast of Alaska at the southern end of Kasega-
luk Lagoon, which is an important wildlife area for both birds and marine mammals. Some ter-
restrial mammal populations representative of that Arctic Coastal Plain ecosystem also occur in
the Point Lay vicinity. The major large terrestrial mammal species in the region include grizzly
bear (Ursus arctos), caribou (Rangifer tarandus), and, perhaps, wolf (Canis lupus). Although
moose (Alces alces) are not common on the coastal plain, a moose was observed at the former
Point Lay Long Range Radar Site (LRRS) in 2006 (Frost et al. 2007). Kasegaluk Lagoon also
supports several important populations of marine mammals, including beluga whale (Delphin-
apterus leucas), spotted seal (Phoca largha), Pacific walrus (Odobenus rosmarus), and polar
bears (Ursus maritimus) (Schoen and Senner 2002).
The Point Lay area is at the northwestern periphery of the range of the Western Arctic Herd
(WAH) of caribou, but is outside the normal summer range for this herd and is at least 100 miles
from the core calving area, although a few individual caribou occasionally do occur in the vicini-
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ty of Point Lay (Schoen and Senner 2002). Caribou are an important subsistence resource for
North Slope village residents, including residents of Point Lay.
Polar bears occur during winter at Point Lay and along the barrier islands of Kasegaluk La-
goon, and bears have been documented as denning in the general region (Schoen and Senner
2002). Both grizzly bears and wolves are found in low densities in the Point Lay area (Schoen
and Senner 2002). Grizzly bear densities also increase in Kasegaluk Lagoon northeastern of
Point Lay where prey species are concentrated (Schoen and Senner 2002).
Kasegaluk Lagoon is also a concentration area for beluga whales during early-mid summer
when they are undergoing molt (Schoen and Senner 2002). Spotted seals also haul out on the
barrier islands of Kasegaluk Lagoon between mid July and September and this area is an im-
portant summer concentration area for this species. Pacific walrus also occasionally use Kasega-
luk Lagoon and the nearshore waters. Bowhead whales (Balaena mysticetus) migrate past Point
Lay during spring and fall.
BIRDS
Bird habitats in the Point Lay area include wetlands (small ponds and lakes) and wet and
moist tundra habitats found along the western coastline of the Arctic Coastal Plain. Bird popula-
tions at Point Lay are representative of those habitats found elsewhere on the western North
Slope. The nearshore and estuarine habitats in Kasegaluk Lagoon also are important to several
species of waterfowl, particularly molting and migrating Brant (Branta bernicla) that stage in the
lagoon during late summer and fall, and molting and migrating Long-tailed Ducks (Clangula hy-
emalis) (Lehnhausen and Quinlan 1981, Schoen and Senner 2002, Lysne et al. 2004). The Audu-
bon Society has designated Kasegaluk Lagoon as an Important Bird Area due to the diversity of
use by birds and the unique habitats in the lagoon (Schoen and Senner 2002).
The Arctic Coastal Plain has been surveyed annually for both breeding eiders and breeding
pairs of other waterfowl by the U.S. Fish and Wildlife Service (USFWS). Unfortunately the eider
survey does not extend far enough south to include Point Lay, but the breeding-pair survey does
cover the Point Lay vicinity (Mallek et al. 2007). The Point Lay area also was included in aerial
surveys for birds using nearshore waters along the Arctic coast by the USFWS from 1999–2003
(Lysne et al. 2004). Studies of bird migration at the northern end of Kasegaluk Lagoon were
conducted in 1981 (Lehnhausen and Quinlan 1981) and surveys to document waterfowl use of
the lagoon were conducted in the late 1980s (Johnson et al. 1992). Bird populations on the Arctic
Coastal Plain are dominated by species associated with wetlands and wet/moist tundra habitats,
primarily waterbirds (loons, gulls, terns, jaegers), waterfowl (Tundra Swan [Cygnus columbi-
anus], geese, ducks), and shorebirds. Smaller numbers of ptarmigan (2 species), raptor and pas-
serine species also occur. Most raptor species nest in the foothills of the Brooks Range rather
than on the coastal plain, but juveniles of some species, particularly Golden Eagles (Aquila
chrysaetos), do disperse onto the coastal plain in late summer (Ritchie et al. 2003).
Recent bird studies conducted at Point Lay have focused on documenting use of the former
Long Range Radar Site by threatened eiders, and breeding-bird populations at the site were also
recorded as part of that study (Frost et al. 2007). The occurrence and estimated breeding densi-
ties for various bird species in the Point Lay area have been derived from the transect surveys
flown by the USFWS, the LRRS study, and other sources (Table 1).
THREATENED AND ENDANGERED SPECIES
Several species of birds listed under the federal Endangered Species Act (ESA) of 1973 (as
amended) may occur in the Point Lay area. Two species of eiders are listed as threatened in
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Alaska: Spectacled Eider (Somateria fischeri) and the Steller’s Eider (Polysticta stelleri). The
Yellow-billed Loon (Gavia adamsii) is a Candidate species for listing and the petition to list this
species is currently under review by the USFWS (USFWS 2007). The nearshore waters of Le-
dyard Bay beginning at least 1 nm offshore from the low-tide line have been designated as criti-
cal habitat for the Spectacled Eider by the U.S. Fish and Wildlife Service (USFWS 2001); this
area includes the nearshore waters of Point Lay. No nests of Spectacled Eiders were found dur-
ing ground searches at the Point Lay LRRS, but a brood observed in 1994 was probably a Spec-
tacled Eider brood, which suggests that nesting may occur in some years (Frost et al. 2007). The
Steller’s Eider breeds in the vicinity of Barrow and has been recorded infrequently in the Point
Lay area (Quakenbush et al. 2002, Frost et al. 2007); recent evidence of breeding in the Point
Lay area is lacking for this species. Yellow-billed Loons regularly migrate along Kasegaluk La-
goon in fall, and possibly spring, but few remain in the area to breed (Lehnhausen and Quinlin
1981, Johnson et al. 1992). A single Yellow-billed Loon was observed at the Point Lay LRRS in
1994 (Frost et al. 2007) but the Point Lay region is not a primary breeding area for this species.
POSSIBLE ENVIRONMENTAL EFFECTS OF THE PROPOSED WINDFARM
HABITAT LOSS
Direct loss of wildlife habitats associated with the construction of the wind turbines and the
powerline to Point Lay is minor (<1 acre) and unlikely to affect wildlife populations in the area.
Some additional functional loss of wildlife habitats in the vicinity of the wind turbines is likely
from disturbance and displacement by the noise and visual stimulus of the moving turbine
blades. However, given the location of the windfarm adjacent to an existing road between the
village and the former Point Lay LRRS, these habitats probably already received somewhat less
use than the undisturbed surrounding tundra.
DISTURBANCE AND DISPLACEMENT
Terrestrial Mammals and Birds
The noise and visual stimuli from the wind turbines are likely to disturb birds and terrestrial
mammals in the immediate vicinity of the windfarm. Subsistence hunting by local residents
probably limits the number of large mammals, such as bears, that occur around the village, which
reduces the likelihood that these species will regularly move through the area around the wind-
farm. Birds are more likely to be disturbed by the operation of the wind turbines and, although
no data are available to determine the relative area of disturbance in an arctic ecosystem, it
would seem unlikely that the disturbance zone would extend more than several hundred meters
from the turbines. Some displacement of breeding birds from the immediate vicinity of the wind
turbines is likely, however, over time, smaller birds may habituate to the noise and visual dis-
turbance of the operating windfarm, but larger waterfowl (swans, geese, ducks) may tend to
avoid the area.
Marine Mammals
Recent studies of the effects of offshore drilling and oil production in the Beaufort Sea on
marine mammals have noted some displacement and disturbance to whales and seals by noise
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emanating from these facilities and from other oil production activities (seismic, blasting, pile
driving, ship traffic), primarily caused by high underwater noise levels and apparent long-
distance propagation of that noise (Richardson et al. 1991, 1995; NMFS 2002; Nowacek 2007).
Richardson et al. (1995) reviewed the studies on effects of offshore drilling islands and found
that although airborne noise during operations was audible at distances of 2 km (1.2 miles) from
the island, noise from the drilling rig transmitted poorly through the land into the nearshore wa-
ters under normal conditions. Concerns have been raised that noise associated with coastal wind-
farms in northern Alaska also could result in disturbance to marine mammals using the adjacent
marine environment. Studies of the effects of windfarms on marine mammals have focused on
offshore windfarms in Europe, where most of the observed impacts were from noise generated
by pile-driving during windfarm construction (Madsen et al. 2006, Thomsen et al. 2006). Once
the offshore windfarm was operational, however, the noise levels of were low and were consid-
ered to be unlikely to affect marine mammals. Noise levels associated with these operating off-
shore wind turbines were at the periphery of the hearing range of pinnipeds and many cetaceans,
thus disturbance from the underwater noise generated by wind turbines was minimal, except
when animals were extremely close to the wind farm (<200–500 m [~650–1640 ft]) (Madsen et
al. 2006).
Information on the possible transmission of noise from onshore windfarms to the marine
environment is sparse. Although noise generated by wind turbines will be unlikely to transmit
through the ground surface and into the adjacent underwater marine environment, the potential
transmission of airborne noise to the ocean surface and below the surface may be possible de-
pending on the noise levels and weather conditions (air temperature and wind) (Richardson et al.
1995). The air-to-water transmission of noise is dependent on several factors: (1) noise level at
the source, (2) distance from the noise source to the ocean surface, and (3) angle of the sound
source to the ocean surface. Also important are water depth, sea bottom type, and sea-surface
state (calm versus waves).
The noise levels associated with the proposed wind turbines are estimated at about 100 dBA
(LMax) at the turbine (at wind speeds of 30 mph) but decrease to 44 dBA at 1500 ft from the wind
turbines and to 35 dBA and 32 dBA at distances of 3200 and 3900 ft, respectively (see Noise
section; M. Minor, pers. comm.). The location of the windfarm at Point Lay, approximately 1.5
miles from the open ocean (i.e., outside the barrier island), should limit the likelihood of trans-
mission of noise into nearby marine waters and thus reduce any potential for disturbance to ma-
rine mammals passing along the coast. Noise levels in the adjacent lagoon may be higher, how-
ever, which could affect any marine mammals in that area.
The angle of the noise source (the wind turbine nacelle and blades) to the sea surface is im-
portant because at angles >13 from the vertical (i.e., directly overhead) noise is completely re-
flected from the sea surface under calm water conditions, although some transmission is possible
under rougher water conditions (where wave fronts may provide suitable angles for noise trans-
mission). The proposed location of the windfarm at Point Lay onshore and at some distance
from the ocean results in a relatively high angle (>45 ) between the turbine noise source and the
sea surface, which indicates that, at least under calm conditions, little to no noise transmission
would likely occur to the underwater zone. During windy conditions, when the windfarm would
be operating at its highest noise levels, the potential for transmission of sound into the rougher
ocean surface would be somewhat greater, but the potential for masking of the windfarm noise
by ambient wind sounds also would be greater.
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During winter and spring when ice is present in the nearshore waters, the transmission of
noise from the windfarm to the water surface is prevented, but noise can penetrate ice depending
on the ice conditions (noise penetrates flat ice more easily than rough or jumbled ice). Richard-
son et al. (1995) reported that construction-related sounds did not propagate well in shallow wa-
ter under the ice in winter and that vehicular traffic on an ice road in 12 m (40 ft) deep water
transmitted little noise below the ice surface.
In summary, the current proposed location of the windfarm at Point Lay would be unlikely
to be a strong disturbance to marine mammals in the nearshore waters, but any potential adverse
effects could be reduced by moving the windfarm farther from the shoreline, if possible.
COLLISION MORTALITY
An environmental concern for almost all operating windfarms is the potential for injuries
and mortalities to birds flying into the wind turbines. For the Point Lay windfarm, the primary
periods of concern would be during spring (May–early June) and fall (August–September) mi-
gration and during the summer breeding season (June–August); few birds overwinter in the area.
The location of the windfarm near the coast and Kasegaluk Lagoon, which supports large popu-
lations of molting and staging waterfowl annually, could increase the potential for collisions if
significant movements of birds along the coast near Point Lay occur regularly (such as feeding
flights by loons or waterfowl, or migratory flights by Brant and other waterfowl, such as Long-
tailed Ducks and eiders). Of particular concern at Point Lay would be any injuries or mortality to
the two listed eider species, Spectacled and Steller’s eiders, or possibly to Yellow-billed Loons,
if they are eventually listed, as these injuries or mortalities would constitute “take” under the
ESA.
INCREASED PREDATION DUE TO HABITAT ENHANCEMENT
The increasing number of towers and other man-made structures on the North Slope are be-
coming a major concern to the USFWS because this infrastructure provides potential nesting
platforms for predatory birds, particularly the Common Raven (Corvus corax), which take the
eggs and young of threatened eiders and other birds species. Common Ravens currently nest on
towers in the North Slope oilfields, often in areas with significant noise and other human disturb-
ance, which suggests that the towers supporting the wind turbines may be attractive to this spe-
cies. Open lattice towers are of particular concern because they provide convenient platforms to
support the stick nests built by ravens. Common Ravens formerly nested at the Point Lay LRRS
facility before it was decommissioned and nesting structures were removed (Frost et al. 2007).
Several other species of raptors, Peregrine Falcons (Falco peregrinus) and Gyrfalcons (F. rusti-
colus), also will use man-made structures as nest platforms (Ritchie 1991, Ritchie et al. 2003);
the latter species has been recorded at the Point Lay LRRS (Frost et al. 2007).
ENVIROMENTAL REGUALTIONS AFFECTING THE PROPOSED WINDFARM
Several federal environmental laws and regulations may be pertinent to the development and
operation of the proposed windfarm.
Endangered Species Act
Migratory Bird Treaty Act
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National Environmental Policy Act
Eagle Protection Act
Clean Water Act
The Endangered Species Act will affect the proposed windfarm because of the presence of the
threatened eider species and the Yellow-billed Loon in the Point Lay area. Consultation with the
USFWS will be required to determine the potential for take of these species under the ESA and
should begin as soon as practical given the time requirements for the consultation process. The
Migratory Bird Treaty Act will be of interest if removal of Common Raven nests is requested by
the USFWS, as this species is protected under the act, which regulates actions that affect nesting
migratory birds. The Eagle Protection Act also protects Golden Eagles, which may be vulnerable
to collisions if they were to occur in the vicinity of the wind turbines at Point Lay. The National
Environmental Policy Act, which requires environmental analyses (such Environmental Assess-
ments or Impact Statements), may not apply to the Point Lay windfarm if federal money or lands
are not involved. The Clean Water Act requires a permit (Section 404 permit) for any dredging
and/or filling of wetlands, which are likely to occur during construction of the wind turbine tow-
ers and powerline.
The State of Alaska and the North Slope Borough may also require permits (e.g., coastal
zone) for activities on lands in the Point Lay area.
LITATURE CITED
Frost, G. V., R. J. Ritchie, and T. Obritschkewitsch. 2007. Spectacled and Steller’s eiders sur-
veys at U.S. Air Force radar sites in northern Alaska, 2006. Unpublished report to U.S.
Air Force, Elmendorf AFB, AK, by ABR, Inc.–Environmental Research and Services,
Fairbanks, AK. 58 pp.
Johnson, S., D. Wiggins, and P. Wainwright. 1992. Part II: marine birds. Pages 58–510 in Use
of Kasegaluk Lagoon, Chukchi Sea, Alaska, by marine birds and mammals. Report to
Mineral Management Service, Herndon, VA. Prepared by LGL Ecological Research As-
sociates and Alaska Department of Fish and Game. MMS 92-0028.
Lehnhausen, W. A., and S. E. Quinlan. 1981. Bird migration and habitat use at Icy Cape, Alaska.
Unpublished report, U.S. Fish and Wildlife Service, Anchorage, AK.
Lysne, L. A., E. J. Mallek, and C. P. Dau. 2004. Near shore surveys of Alaska’s Arctic coast.
Unpublished report by U.S. Fish and Wildlife Service, Migratory Bird Management,
Fairbanks, AK. 57 pp.
Mallek, E.J., R. Platte, and R. Stehn. 2007. Aerial breeding pair surveys of the Arctic Coastal
Plain of Alaska–2006. Unpublished report by U.S. Fish and Wildlife Service, Migratory
Bird Management, Fairbanks, AK. 56 pp.
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Madsen, P. T., M. Wahlberg, J. Tougaard, K. Lucke, and P. Tyack. 2006. Wind turbine underwa-
ter noise and marine mammals: implications of current knowledge and data needs. Ma-
rine Ecology Progress Series 309: 279–295.
NMFS. 2002. Biological Opinion for Endangered Species Section 7 Consultation and operation
of the Liberty oil production island (Consultation No. F/AKR/2001/00889). Prepared by
National Oceanic and Atmospheric Administration, National Marine Fisheries Service for
the U. S. Department of Interior, Minerals Management Service, Anchorage, AK. 51 pp.
Nowacek, D. P., L. H. Thorne, D. W. Johnston, and P. L. Tyack. 2007. Responses of cetaceans
to anthropogenic noise. Mammal Review 37: 81–115.
Richardson, W. J., C. R. Greene, Jr., C. I. Malme, and D. H. Thomson. 1991. Effects of noise on
marine mammals. U. S. Minerals Management Service, Herndon, VA. OCS Study MMS
90-0093. 462 pp.
Richardson, W. J., C.R. Greene, C. I. Malme, and D. H. Thomson. 1995. Marine Mammals and
Noise. Academic Press, San Diego, CA.
Ritchie, R. J. 1991. Effects of oil development on providing nesting opportunities for Gyrfalcons
and Rough-legged Hawks in northern Alaska. Condor 93: 180-184.
Ritchie, R. J., A. M. Wildman, and D. A. Yokel. 2003. Aerial Surveys of Cliff-nesting Raptors in
the National Petroleum Reserve-Alaska, 1999, with comparisons to 1977. Technical Note
413. Bureau of Land Management, Denver, CO. BLM/AK.ST-03/016+6501+023. 66 pp.
Schoen, J., and S. Senner. 2002. Alaska’s Western Arctic: A summary and synthesis of re-
sources. Unpublished report by Audubon Alaska, Anchorage, AK. (Available on CD).
Thomsen, F., K. Ludemann, R. Kafemann, and W. Piper. 2006. Effects of offshore wind farm
noise on marine mammals and fish. Unpublished report prepared by Biola, Hamburg,
Germany, for COWRIE, Ltd. (Available online at
http://www.offshorewindfarms.co.uk/Downloads/BIOLAReport06072006FINAL.pdf)
U.S. Fish and Wildlife Service. 2001. Endangered and threatened wildlife and plants: final de-
termination of critical habitat for the Spectacled Eider. Federal Register 66 (25): 9146–
9185.
U.S. Fish and Wildlife Service. 2007. Endangered and threatened wildlife and plants: 90-day
finding on the petition to list the Yellow-billed Loon as threatened or endangered. Federal
Register 72 (108): 31256–31264.
116/214 Table 1. Estimates of breeding populations of birds in the Point Lay region, northern Alaska. Species Breeding Density Estimate Survey Type SourceYellow-billed LoonGavia adamsii No breeding birds observed in im-mediate village area of Point Lay, nearest low-density breeding area is near Wainwright USFWS Aerial Breeding-pair Surveys, 1998-2001 Schoen and Senner 2002 (Figure II 2.01) Pacific Loon Gavia pacifica1 nest at Point Lay LRRS in 1994, 2002, 2003, 2006Ground-based Nest Search at Point Lay Former LRRSFrost et al. 2007 Red-throated Loon Gavia stellata None observed in immediate village area of Point Lay, low density area is inland to southwest and high density area ~10 mi southeast USFWS Aerial Breeding-pair Surveys, 1998-2001 Schoen and Senner 2002 (Figure II 2.06) 1 nest observed in 2002, 2003 Ground-based Nest Search at Point Lay Former LRRSFrost et al. 2007 Greater White-fronted Goose Anser albifrons Low breeding density at Point Lay; Medium–high breeding density ~10-20 miles southeast USFWS Aerial Breeding-pair Surveys, 1998-2001Schoen and Senner 2002 (Figure II 2.02) 3 nests in 2002, 1 nest in 2003 Ground-based Nest Search at Point Lay Former LRRS Frost et al. 2007 Brant Branta berniclaNone observedUSFWS Aerial Breeding-pair Surveys, 1998-2001Schoen and Senner 2002 (Figure II 2.03)Greater Scaup Athya marila1 nest in 2000Ground-based Nest Searchat Point Lay Former LRRSFrost et al. 2007Spectacled Eider Somateria fischeriNo breeding at Point Lay, but near-shore waters (1 nm offshore) are des-ignated as critical habitat USFWS Eider Breeding Population Surveys, 1998-2001Schoen and Senner 2002 (Figure II 2.04)1 brood considered to be Spectacled Eider in 1994Ground-based Nest Searchat Point Lay Former LRRSFrost et al. 2007King Eider Somateria spectabilisNo breeding at Point Lay; nearest breeding area is northeast near Icy Cape USFWS Eider Breeding Population Surveys, 1998-2001Schoen and Senner 2002 (Figure II 2.07)
117/214 Table 1. (cont.). Species Breeding Density Estimate Survey Type SourceCommon EiderSomateria mollissima 1 nest in 2002, 4 nests in 2003 Ground-based Nest Search at Point Lay Former LRRS Frost et al. 2007Long-tailed Duck Clangula hyemalis Low breeding density at Point Lay; Medium-High breeding density sev-eral miles to east USFWS Aerial Breeding-pair Surveys, 1998-2001Schoen and Senner 2002 (Figure II 2.08) Willow Ptarmigan Lagopus lagopus2 nests in 2000Ground-based Nest Searchat Point Lay Former LRRSFrost et al. 2007Shorebirds (large-bodied species) Low breeding density; Medium–High densities ~10-20 miles to southeast of Point Lay USFWS Aerial Breeding-pair Surveys, 1998-2001Schoen and Senner 2002 (Figure II 2.04)Semipalmated Sandpiper Calidris pusilla2 nests in 1994, 2002, 2003 Ground-based Nest Search at Point Lay Former LRRSFrost et al. 2007 Western SandpiperCalidris mauri 1 nest in 2003 Ground-based Nest Search at Point Lay Former LRRS Frost et al. 2007Pectoral Sandpiper Calidris melanotos 1 nest in 2002, 2006Ground-based Nest Searchat Point Lay Former LRRS Frost et al. 2007Wilson’s Snipe Gallinago delicataNesting probable (breeding males displaying) in 2003, 2006Ground-based Nest Searchat Point Lay Former LRRSFrost et al. 2007Long-billed DowitcherLimnodromus scolopaceus2 nests in 2003Ground-based Nest Searchat Point Lay Former LRRSFrost et al. 2007Red-necked Phalarope Phala-ropus lobatus3 nests in 1994, 2 nests in 2002 Ground-based Nest Searchat Point Lay Former LRRSFrost et al. 2007Red Phalarope Phalaropus fulicarius1nest in 1994, 2006Ground-based Nest Searchat Point Lay Former LRRSFrost et al. 2007Pomarine Jaeger Stercorarius pomarinus1 nest in 2006Ground-based Nest Searchat Point Lay Former LRRSFrost et al. 2007Glaucous GullLarus hyperboreus2nests in 2002, 2003; 1 nest in 2006Ground-based Nest Searchat Point Lay Former LRRSFrost et al. 2007
118/214 Table 1. (cont.). Species Breeding Density Estimate Survey Type SourceArctic Tern Sterna paradisaea 1 nest in 2003 Ground-based Nest Search at Point Lay Former LRRS Frost et al. 2007Common Raven Corvus corax 1 nest in 1994, 2002, 2003(on build-ings) Ground-based Nest Search at Point Lay Former LRRS Frost et al. 2007Eastern Yellow Wagtail Motacilla tschutschensisNesting in 1994, 2000–2003, 2006 Ground-based Nest Search at Point Lay Former LRRSFrost et al. 2007 Savannah Sparrow Passerculus sandwichensis Nesting in 1994, 2000–2003, 2006Ground-based Nest Search at Point Lay Former LRRS Frost et al. 2007Lapland Longspur Calcarius lapponicus Nesting in 1994, 2000–2003, 2006Ground-based Nest Search at Point Lay Former LRRS Frost et al. 2007Snow Bunting Plectrophenax nivalisNesting in 1994, 2003, 2006 Ground-based Nest Search at Point Lay Former LRRSFrost et al. 2007