Nearshore ecosystems in the Gulf of Alaska (Exxon Valdez Oil Spill Trustee Council Project 22120114-H)
Coletti H, Esler D, Iken K, Konar B, Ballachey B, Bodkin J, Esslinger G, Kloecker K, Lindeberg M, Monson D, Robinson B, Traiger S, Weitzman B. 2023. Nearshore ecosystems in the Gulf of Alaska (Exxon Valdez Oil Spill Trustee Council Project 22120114-H). Exxon Valdez Oil Spill Trustee Council. Anchorage, Alaska
We conducted nearshore marine ecosystem monitoring in four regions within the spill-affected area of the northern Gulf of Alaska (GOA): western Prince William Sound (WPWS), Kenai Fjords National Park (KEFJ), Kachemak Bay (KBAY), and Katmai National Park and Preserve (KATM). The nearshore monitoring program focuses on sampling numerous ecosystem components in the GOA that are both numerically and functionally important, including kelps (and other marine algae), seagrasses, marine intertidal invertebrates, marine birds, black oystercatchers, sea otters, and physical properties. Our nearshore monitoring has been carefully designed, with coordinated sampling of all metrics, to provide insights into drivers of change observed at different spatial and temporal scales. Our objectives are as follows: • Determine status and detect patterns of change in a suite of nearshore species and communities. • Identify temporal and spatial extent of observed changes. • Identify potential causes of change in biological communities, including those related to climate change. • Communicate these to the public and to resource managers to conserve nearshore resources. • Continue restoration efforts to evaluate the current status of spill-injured resources and identify factors potentially affecting present and future trends in population and ecosystem status. The design features of the Nearshore Component include a rigorous site selection process that allows statistical inference over various spatial scales (e.g., GOA and regions within the GOA) as well as the capacity to evaluate potential impacts from more localized sources, and especially those resulting from human activities, including lingering effects of the Exxon Valdez oil spill (EVOS). In addition to detecting change at various spatial scales, design features incorporate both static (e.g., substrate, exposure, bathymetry) and dynamic (e.g., variation in oceanographic conditions, productivity, and predation) drivers as potential mechanisms responsible for change. More than 200 species dependent on nearshore habitats, many with well recognized ecological roles in the nearshore food web, are monitored annually within four regional blocks in the GOA. Evaluation of change in those species over time in relation to well defined static and dynamic drivers allows accurate and defensible measures of change and supports management and policy needs addressing nearshore resources. In 2022, we completed all aspects of the nearshore monitoring component across all four regions. The status of all measured metrics was reported on recently (Coletti et al. in review – EVOS 2017-2021 final report) through 2021. For the 2022 annual report, we are reporting on intertidal water temperature and several intertidal indicators that represent key nearshore ecosystem components of primary production and prey abundance. Upper-trophic level predator trends through 2022 are still being analyzed.
- Type
- Published Report
- Authors
- Coletti, Heather; Esler, Dan; Iken, Katrin; Konar, Brenda; Ballachey, Brenda; Bodkin, James; Esslinger, George; Kloecker, Kim; Lindeberg, Mandy; Monson, Dan; Robinson, Brian; Traiger, Sarah; Weitzman, Benjamin
- Date of Issue
- 2023-03
- Publisher
- Exxon Valdez Oil Spill Trustee Council
- Units
- KATM , KEFJ , SWAN
- Keywords
- benthic invertebrates, black oystercatchers, Gulf of Alaska, intertidal, Kachemak Bay, Katmai National Park and Preserve, Kenai Fjords National Park, macroalgae, marine birds, monitoring, nearshore marine ecosystem, Prince William Sound, sea otters
- Subjects
- Ecological Framework: Biological Integrity | Focal Species or Communities | Marine Communities , Ecological Framework: Biological Integrity | Focal Species or Communities | Intertidal Communities , Ecological Framework: Biological Integrity | Focal Species or Communities | Marine Invertebrates , Ecological Framework: Biological Integrity | Focal Species or Communities | Birds , Ecological Framework: Biological Integrity | Focal Species or Communities | Mammals