Section 1 Introduction - National Marine Fisheries Service - NOAA

NBK at Bangor EHW-1 Pile Replacement Project Final Marine Mammal Monitoring Report
Species
Table 10. Summary of Underwater and Airborne Marine Mammal Takes
During the EHW-1 PRP
Total
Authorized
Take for
the Entire
Project 1
Portion of
Authorized
Takes for
Steel Pile
Installation
(14 days)
and
Removal
(2 days) 2
Total
Number
of
Takes 3
Underwater
Injury Zones
(No. of Animals)
190 dB
RMS
180 dB
RMS
Underwater Harassment
Zones
(No. of Animals)
120 dB
RMS
(Actual)
120 dB
RMS
(Extrapolated)
Airborne
Harassment
Zones
(No. of Animals)
100
dB
RMS
Harbor seal 1,766 836 67 0 0 59 8 0 0
California sea
lion
558
268
167 0 0 137
90 dB
RMS
Bangor, Washington 37
30
0 0
Killer whale 58 30 0 0 0 0 0 0 0
Dall’s
porpoise
Harbor
porpoise
71
64 4
32
16
0 0 0 0
10 0 0 5
0
5
0 0
0 0
Steller sea lion 0 0 2 0 0 1 1 0 0
TOTAL 2517 4 1182 246 0 0 202 44 0 0
Notes:
1 This column represents the total number of takes authorized in the modified IHA dated 10-18-11.
2 This column represents the number of takes requested (and later authorized) for steel pile installation and steel pile
removal based on the calculations in the initial IHA application which broke up takes by pile installation/removal activity.
For example, for the harbor seal, 742 takes were requested (pg 68 of IHA application) for 14 days of steel pile installation
and 987 takes were requested for 21 days of steel pile removal. During the first in-water work window (2011) the Navy
used all 14 days of authorized steel pile installation, but only two days of steel pile removal. In order to determine the
takes used using the same mathematical approach as in the initial application, the Navy divided the total number of takes
requested in that application for steel pile installation (742) by the total number of days requested for steel pile installation
(14) to get a daily take number of 53. Likewise for steel pile removal, 987 takes were divided by the total number of
days requested for steel pile removal (21) to get a daily take number of 47. Then the daily number was multiplied by the
actual number of days used during the 2011 work. So for pile installation, 53 daily takes was multiplied by 14 actual
installation days for a total of 742 takes. For pile removal, 47 daily takes was multiplied by 2 actual removal days for a
total of 94 takes. Summing these two numbers together (742+94) results in a total of 836 takes expected during pile
installation and pile removal activity from 2011 construction days. These calculations were followed for the other
species.
3 Includes extrapolated takes for the 120 dB Behavioral Harassment zone.
4 In the original IHA dated 5-17-11 (published in the FR on 5-24-11), there were 35 takes authorized for the harbor
porpoise. In the modified IHA, dated 10-18-11, there were 64 harbor porpoises authorized. The total number includes
the 64 authorized.
All 246 animals were Level B underwater takes (Table 10). In order to qualify as an airborne
take, pinnipeds had to 1) be hauled out within the airborne harassment ZOI, or 2) have their head
above the water for the duration of the pile driving event (or sighting) (NMFS pers. comm. with
Navy, 2012). Of the 19 animals (all harbor seals) that were seen within the airborne ZOI (see
Appendix F), all were recorded as sinking or diving during pile driving (see Appendix F), and
therefore did not qualify as airborne takes. The airborne harassment threshold for sea lions and
Steller sea lions (100 dB) reached a maximum of 16 m during the EHW-1 PRP, and no animals
of either species were seen within this radius during any construction event. California sea lions
typically hauled out along the port security barrier (approximately 500 m to 700 m from the