Section 1 Introduction - National Marine Fisheries Service - NOAA

NBK at Bangor EHW-1 Pile Replacement Project Final Marine Mammal Monitoring Report
Marine Mammal Behavior During the EHW-1 PRP
Quantitative Analysis.
Marine mammal behavior was recorded during both construction and non-construction periods
(Appendix E), and was analyzed by: (1) distance from the pile (during construction only), (2)
construction vs. non-construction periods, (3) pre-, during, and post-watch periods, and 4) type
of construction activity. Note that animals may have been engaged in one or more behaviors
during a given sighting. Behavior codes are found in Appendix D.
The only cetacean observed during the EHW-1 PRP was the harbor porpoise. During the 12
cetacean sightings, four types of behaviors (n=17) were recorded. During the monitoring effort
(construction and non-construction periods), cetaceans were most often observed “swimming”
(n=12; 70.6%) (Figures 11 and 12).
Pinnipeds observed during the EHW-1 PRP were the harbor seal, California sea lion, and Steller
sea lion. During the 364 combined pinniped species sightings, 16 types of behaviors (n=859)
were recorded. During the monitoring effort (construction and non-construction periods),
pinnipeds were most frequently observed “swimming” (n=182; 21.2%), “diving” (n=170;
19.8%), “looking” (n=149; 17.3%), and “sinking” (n=99; 11.5%) (Figures 13 and 14).
Analysis of Behavior by Distance from Pile. Behavior was analyzed as a function of distance
from pile for sightings made during monitoring of construction activities (refer to Appendix E).
Distance categories for the monitored zones for analyses were: (1) the shutdown zone (50 m [164
ft]); the 51 m to 6,000 m (167 to 19,685 ft) behavioral harassment zone (buffer zone); and the
area beyond 6,000 m (19,685 ft or 6,562 yards).
Cetaceans
There were three cetacean sightings that occurred during construction activity (Table 15; green
shaded lines in Appendix E). None of these sightings occurred within the shutdown zone (50 m
[164 ft]). All cetacean sightings during construction activity were in the monitored buffer zone
(Level B behavioral harassment) at distances of 51 to 6,000 m (167 to 19,685 ft) from the pile
(Table 15). The only observed cetacean behaviors during construction activity were
“swimming” (n=3; 75%) and diving (n=1; 25%) (Table 15). No cetacean sightings were
recorded during construction activities beyond the monitored buffer zone for vibratory pile
driving.
Pinnipeds
There were 114 pinniped sightings that occurred during construction activity (Table 16; green
shaded lines in Appendix E). Observations included behaviors within all zones of the
construction area, but not beyond the average 5.4 km buffer (Level B harassment) zone. There
were 17 pinniped sightings within the 50m (164ft) safety zone during construction activity, with
a total of 19 records encompassing six types of behavior. The most common pinniped behaviors
within 50 m (164 ft) of piles were “looking” (n=6; 3.9%) and “diving” (n=5; 3.25%) (Table 16).
There were 97 pinniped sightings in the buffer zone between 51 and 6,000 m for a total of 128
records encompassing 13 types of behavior. The most common pinniped behaviors between 51
and 6,000 m of piles were “swimming” (n=25; 16.23%), “looking” (n=24; 15.58%), and
“diving” (n=21; 13.63%) (Table 16). No pinniped sightings were recorded during construction
activities beyond the monitored buffer zone for vibratory pile driving.
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