Arctic Long-Term Integrated Mooring Array 2016 Cruise Report

December 05, 2016

The 2016 Arctic Long-Term Integrated Mooring Array (ALTIMA) cruise took place on board the F/V Aquila. The cruise began in Nome, AK on 3 September 2016 and ended in Dutch Harbor, AK on 29 September 2016. Chief Scientist was Dr. Catherine Berchok, and the survey team consisted of 14 scientists representing eight different laboratories or institutions (for full personnel list, see Appendix 1). In summary, a total of 18 passive acoustic, 14 oceanographic, and 5 combination (oceanographic/ passive acoustic) moorings were retrieved, and 19 passive acoustic, 18 oceanographic, and 5 combination moorings were redeployed. A total of 71 CTD casts were conducted, 48 zooplankton net tows were done, one drifter was deployed, ~2700 nm were sampled using a new underway oceanographic sampling system, and a new acrobat towfish sampled ~270 nm. A total of 142 sonobuoys were deployed for 24 hour passive acoustic monitoring, and over 1140 nm were surveyed for marine mammals and 126 hours were surveyed for seabirds.

The western Arctic physical climate is rapidly changing. The Arctic sea ice extent reached a new low in maximum extent on March 24, 2016, breaking the record for the second year in a row (http://tinyurl.com/gw5xoo8). The maximum extent was 14.52 million square kilometers which is 1.12 million square kilometers below the 1981 to 2010 average of 15.64 million square kilometers. The speed of this ice loss was unexpected, as the consensus of the climate research community was that this level of ice reduction would not be seen for another thirty years. As sea temperature, oceanographic currents, and prey availability are altered by climate change, parallel changes in baleen whale species composition, abundance and distribution are expected (and evidenced already by local knowledge and opportunistic sightings). In addition, the observed northward retreat of the minimum extent of summer sea ice has the potential to create opportunities for the expansion of oil and gas-related exploration and development into previously closed seasons and localities in the Alaskan Arctic. It will also open maritime transportation lanes across the Arctic adding (to a potentially dramatic degree) to the ambient noise in the environment. This combination of increasing anthropogenic impacts, coupled with the steadily increasing abundance and related seasonal range expansion by bowhead (Balaena mysticetus), gray (Eschrichtius robustus), humpback (Megaptera novaeangliae) and fin whales (Balaenoptera physalus), mandates that more complete information on the year-round presence of large whales is needed in the Chukchi Sea planning area. Timing and location of whale migrations may play an important role in assessing where, when, or how exploration or access to petroleum reserves may be conducted, to mitigate or minimize the impact on protected species.

Last updated by Alaska Fisheries Science Center on 12/07/2018

Research in Alaska Cetacean Assessment and Ecology Program Marine Mammals