Biological Opinion U.S. Department of Navy Ice Exercise 2024 Arctic, Beaufort Sea, Alaska

This opinion considers the effects of the Navy’s Ice Exercise (ICEX 2024)
in the winter/spring of 2024. These actions have the potential to affect the threatened Arctic
subspecies of ringed seal (Phoca (Pusa) hispida) but will have no effect to critical habitat.
Critical habitat only overlaps with the flight corridor. Physical and biological features that are
necessary to conserve the Arctic subspecies of ringed seals included sea ice habitat and
primary prey needed to maintain ringed seal energy budgets. Critical habitat is not expected
to be altered by periodic overflight of aircraft. Therefore, effects to critical habitat are not
considered in this Opinion. The bowhead whale (Balaena mysticetus) was not included in the
IHA application because bowhead whales migrate to the west and south in the winter and will
not be present in the action area. Likewise, the bearded seal (Erignathus barbatus nauticus)
is not expected to be within the vicinity of the action area. Therefore, neither bowhead
whales nor bearded seals are considered in this Opinion.

The proposed action involves the establishment of a temporary base camp on Arctic ice in the
Beaufort Sea approximately 100–200 nautical miles (nm) north of Prudhoe Bay, Alaska (Figure
1). The base camp will support submarine training and testing under Arctic conditions, test
emerging technologies and their capabilities in the Arctic, and gather data on Arctic
environmental conditions. The proposed construction, use, and demobilization of the camp
will occur over a six-week period from February to April 2024.

This opinion is based on information provided in the July 2023 and revised October 2023
Biological Evaluation (BE) for the project, the October 2023 Revised Request for an Incidental
Harassment Authorization (IHA), and the September 2023 Draft Supplemental Environmental
Assessment/Overseas Environmental Assessment (EAOEA) for the Ice Exercise Program. Other
sources of information relied upon include clarifying emails between NMFS and Navy staff,
stock assessment reports, monitoring reports, and relevant peer reviewed literature. A
complete record of this consultation is on file at NMFS’s Juneau, Alaska office.