Spectacled Eiders (Somateria fischeri) and
Steller’s Eiders (Polysticta stelleri) occur on the
Colville River Delta and are listed as threatened
species under the Endangered Species Act (ESA).
ConocoPhillips Alaska, Inc. (CPAI) operates the
Alpine Satellite Development Project (Alpine
Oilfield), an oil and gas development on the
Colville River Delta, in areas of potential breeding
habitat for these 2 species of eiders. The
Spectacled Eider is a common nester in the
northern parts of the Colville River Delta, while
the Steller’s Eider is rarely sighted on the Colville
River Delta and no nests or broods have been
recorded on the delta. The nesting range of
Steller’s Eiders once included the Colville River
Delta, but over the last 3–4 decades that range has
retracted westward to the Barrow area. To comply
with the ESA and to avoid disturbance of
Spectacled Eiders during the nesting season, CPAI
documented the location of Spectacled Eider nests
in areas slated for off-pad activities (e.g., tundra
clean-up, surveying, spill prevention). Once the
locations of active nests were identified, CPAI
delayed scheduled work activities near the nest
locations until after the nesting season or, if it was
necessary to pre-deploy boom across the river
channel to comply with CPAI’s Oil Discharge
Prevention and Contingency Plan, nest attendance
by eiders was closely monitored to document the
fate of the nests near boom deployment sites.
This is the third year CPAI has contracted
ABR, Inc., to conduct nest searches for eiders in
areas where off-pad work was scheduled during the
eider nesting season. In 2011, these areas included
the CD-3 pad and airstrip, the ice road from CD-2
to CD-3, and 14 Alaska Clean Seas (ACS)
spill-response equipment sites. Other ACS sites
were evaluated for suitable eider nesting habitat
during the 2009 and 2010 nesting season, but were
excluded from the 2011 nest search because either
eider habitat was lacking at a specific site or no
activities were scheduled at these sites during the
eider nesting season. Search areas were delineated
as 200-m buffers around identified work sites. The
search area for the ice road was a 200-m buffer on
each side of the ice road centerline.
In 2011, a total of 5 Spectacled Eider, 1 King
Eider (Somateria spectabilis), and 1 unidentified
eider nests were discovered during nest searches.
One of the active Spectacled Eider nests was
located outside the search buffer >200 m from the
ice road centerline. Three Spectacled Eider nests (2
active and 1 inactive) and 1 unidentified eider nest
(inactive) were found in the CD-3 pad and airstrip
buffers. One active Spectacled Eider nest was
found in the search buffer at ACS Site 3, and 1
inactive King Eider nest was found in the search
buffer at ACS Site 9. We found no Steller’s Eiders
or their nests in any of the areas searched in 2011.
ABR provided CPAI field environmental
compliance staff the coordinates of active eider
nest locations. CPAI staff then instructed the
helicopter pilots and off-pad workers of areas to
avoid. At the end of the nesting season, 2 of the 4
Spectacled Eider nests that were active when
discovered hatched young. A time-lapse camera
was placed to monitor the Spectacled Eider
nest at ACS Site 3 during deployment of
spill-containment equipment; camera images
documented that nest’s failure from arctic fox
predation, which was unrelated to the activities
during deployment. Workers at Site 3 may have
caused the incubating eider to conceal on its nest,
but the hen maintained normal incubation and did
not leave the nest during work at the site.
A review was conducted of Spectacled Eider
nest locations recorded in 2011 and previous years
along with an assessment of nesting habitat
available in the areas searched. Based on the
review and assessment, we recommend continuing
nest searches around the CD-3 pad and airstrip, ice
road, 12 of 19 the spill-response sites, and all 3
pipeline-bridge sites, if off-pad activities are
expected in these locations during the 2012
breeding season.