Marine Bird Distribution and Abundance in Offshore Waters

This study provided current data, as well as seasonal comparisons, of the distribution and abundance of marine birds, and secondarily for marine mammals, within BOEM's Arctic Planning Areas. We conducted seabird surveys for a total of 32,779 km within the focal study area, comprising six BOEM Planning Areas from May to December, 2017–2021. For all planning areas combined, 10 species accounted for 90% of total birds recorded on transect and species composition was similar between summer (June-August) and fall (September–November). Seabird density was highest in Hope Basin followed by Navarin Basin and Norton Sound. We recorded 18 marine mammal species and 4,580 individuals, primarily walruses (Odobenus rosmarus) in the Chukchi Sea and gray whales (Eschrichtius robustus) in Hope and Norton basins. We tagged 92 red phalaropes (Phalaropus fulicarius) at Arctic-breeding sites in Alaska (2017–2020); most individuals migrated west and then south through the Bering Strait, after which, individual routes tended to diverge as individuals migrated along both the Russian and Alaskan coastlines. The high abundance of both seabirds and marine mammals in the Bering Strait region, including Hope Basin, necessitates careful mitigation of human activities in this region. The cumulative effects on seabirds of changes in oceanographic conditions, prey types and distribution, and human activities will need to be considered when assessing potential impacts of proposed developments.

USD: $500,000

2017-07-25 → 2022-09-30