Quiero saber acerca de...

16330

Federal Register / Vol. 86, No. 58 / Monday, March 29, 2021 / Notices
TABLE 1MODELED RADIAL DISTANCES FROM HRG SURVEY EQUIPMENT TO ISOPLETHS CORRESPONDING TO LEVEL A
HARASSMENT AND LEVEL B HARASSMENT THRESHOLDSContinued Distance to level B
harassment threshold m
Sound source
Edgetech 216
Edgetech 424
Edgetech 512i
Teledyne Benthos Chirp III
Kongsberg GeoPulse
Innomar SES2000 Medium-100 Parametric
Applied Acoustics S-Boom Triple Plate
Applied Acoustics S-Boom

The equation for estimating take for all species remains the same as the initial IHA:
Estimated Take = D ZOI of days Where: D = species density per km2
and ZOI = maximum daily ensonified area In the original 2019 IHA application, Atlantic Shores calculated a conservative ZOI by applying the maximum radial distance for any category and type of HRG survey equipment considered in its assessment to the mobile source ZOI calculation.
This maximum calculated distance to the Level B harassment threshold for the sparker of 372 m was also used to calculate the ZOI for the requested extension. The resulting ZOI is 41.36
square kilometers km2.
This methodology of calculating take in the initial IHA applies to the proposed renewal IHA for all species, with the only difference being the fewer amount of days i.e., 234 versus 350.
The result is that the amount of take is reduced proportionally to the reduction in the number of days of work remaining. As was done in the initial IHA, in some cases, Atlantic Shores has requested a deviation from the calculated take for some species given it does not account for group size. In other cases, the requested amount of proposed take deviates from the calculated take based on observations during the 2020
surveys. Other than in the instances described below, NMFS agrees with Atlantic Shores request for take and we
propose to authorize the same amount of take as described in their request.
As described in the renewal IHA
request, large groups of common dolphins commonly approached the HRG survey vessels to bow ride during the 2020 surveys. Despite completing approximately 56.7 percent of the planned survey distance, Atlantic Shores reported using 67.3 percent of total take authorized in the initial IHA
for this species. In 2019, the IHA
application used seasonal density data to calculate requested take for 544
common dolphins. However, 2020
survey activities resulted in 366 takes accumulated for this species, which involved 58 common dolphin detection events where the mean pod size reported was 6.79. For the 2021 surveys, Atlantic Shores is requesting 406
common dolphin takes based on an encounter rate similar to that observed in 2020 58 detection events 7
animals/group. However, NMFS
proposes to authorize the same amount of take of common dolphins as authorized in the initial IHA 544.
Recently, NMFS has modified or proposed to modify other HRG IHAs in the same geographic region due to underestimates of take for bowriding dolphins e.g., 86 FR 13695, March 10, 2021; 85 FR 55415, September 8, 2020.
Because of these experiences, we have determined this approach is necessary to ensure take is not exceeded.
In the initial IHA application, Atlantic Shores also adjusted calculated take per the equation above to consider group
5 6
7 71
231
116
97
56

size for Rissos dolphin, Atlantic spotted dolphins, and long-finned pilot whales.
As described in Atlantic Shores interim monitoring report, they did not observe any of these species during the 2020
surveys. Therefore, we have carried over the same amount of take as proposed in the initial IHA. Atlantic Shores is also requesting the same amount of sei whale take as authorized in the previous IHA
based on an encounter during 2020
survey operations where a single sei whale surfaced inside the Level B
exposure zone resulting in a take.
Finally, during consideration of this renewal request, an error in the application information supporting the harbor porpoise take estimate was identified. Specifically, the density for harbor porpoise was accurate; however, the calculated take for each lease area was incorrectly reported which led to an inaccurate total take amount. The amount of take authorized in the 2020
IHA was 115 when it should have been 847 based on the method used. The correct take estimate for the remaining survey lines covered under the renewal, using that same method, would be 266
takes of harbor porpoise. However, zero harbor porpoises were detected during the 2020 surveys, suggesting that the corrected estimate would likely be an overestimate and the number of takes authorized in the initial IHA is sufficient, and therefore NMFS proposes to authorize the same number of harbor porpoise take included in the initial IHA 115.

TABLE 2INITIAL IHA TAKE AUTHORIZED AND RENEWAL IHA PROPOSED TAKE
Level B harassment Species
Take authorized initial IHA

North Atlantic right whale
Humpback whale
Fin whale
Sei whale

VerDate Sep<11>2014

17:20 Mar 26, 2021

Jkt 253001

PO 00000

Frm 00011

Fmt 4703

Sfmt 4703

E:FRFM29MRN1.SGM

Proposed take renewal IHA

9
18
20
2

29MRN1

8
8 9
12

Percent of Population 5

1.9 <1 <1 <1