Alaska Science Center
The Alaska Science Center, and in preceding Department of Interior agencies, has been engaged in monitoring various sea otter populations for more than 50 years, since Karl Kenyon’s seminal work in the Aleutian Islands. As sea otter populations have recovered from the fur trade and translocations contributed to expanding populations, the task of sea otter monitoring has become increasingly difficult simply because of the vast and remote nature of sea otter habitat. Moreover, it has become increasingly evident that monitoring of single species, while perhaps necessary for management purposes, often provides little insight as to why changes in abundance occur over time. As a result we have been engaged in the development, design and testing of monitoring protocols for nearshore habitats and species, including sea otters, that might best be described as “ecosystem” or “food web” based monitoring.
The nearshore is considered an important component of the Gulf of Alaska ecosystem, including the region affected by the Exxon Valdez oil spill, because it provides:
The underlying assumption in our monitoring design is that change will occur, and that careful consideration of what to monitor, may eventually provide insight as to why observed change occurred. In the nearshore ecosystem we work in, primary productivity is provided by at least two independent sources, the micro-algae, or phytoplankton, that occurs near the sea surface and may be transported inshore via currents. The second, and sometimes major contributor to total primary production is through the kelps and sea grasses that are conspicuous features of the nearshore zone. These combined sources of carbon fuel a diverse community of invertebrates, such as mussels, clams, snails, crustaceans, and urchins, that ultimately transfer their energy to various higher trophic level invertebrates and vertebrates, such as fishes, birds (shore birds, sea ducks and others) and mammals (primarily sea otters). Through careful selection of species and processes (growth, survival and diet) we expect to gain a better understanding of the interaction between various trophic levels that will allow us to potentially assign cause to some of the change we expect to see over time.
As part of the planning efforts of the Exxon Valdez Trustee Council for a long-term science program, in 2001 we were tasked to develop a science and monitoring program for the nearshore ecosystem in the Gulf of Alaska. Through a process of workshops and consultations we developed the Nearshore Restoration and Ecosystem Monitoring program (N-REM, Dean and Bodkin 2006). Coincident with our planning efforts for the Exxon Valdez Trustte Council, the National Park Service was implementing a strategy known as “vital signs monitoring” to develop scientifically sound information on the status and long-term trends of park ecosystems and to determine how well current management practices are sustaining those ecosystems. Subsequently, Park managers from the Southwest Alaska Network (SWAN) recognized that the program we designed for the Exxon Valdez Trustee Council fit their Vital Signs needs and a new partnership was established to implement long term monitoring in the nearshore marine habitat of the SWAN parks.SWAN consists of five Alaskan park units (Aniakchak National Monument and Preserve, Alagnak National Wild River, Katmai National Park and Preserve, Kenai Fjords National Park, and Lake Clark National Park and Preserve). Collectively these units comprise 9.4 million acres or 11.6 percent of the total land area managed by the National Park Service. Network parks encompass climatic conditions, geologic features, near pristine ecosystems, natural biodiversity, freshwater, and marine resources equaled few places in North America. This network of relatively untouched wilderness parks is a unique resource and offers unparalleled opportunities to study and monitor ecological systems minimally affected by humans. In recognition of this, the SWAN monitoring framework emphasizes (i) establishing reference conditions representing the current status of park, monument, and preserve ecosystems; and (ii) detecting ecological change through time. In 2008, The Exxon Valdez Trustee Council adopted and implemented our nearshore monitoring design in Prince William Sound, extending the SWAN nearshore program from the Gulf of Alaska into Prince William Sound and Kachemak Bay in Cook Inlet. The Gulf of Alaska nearshore monitoring program now consists of four primary sites, including Prince William Sound, Kenai Fjords National Park, Kachemak Bay and Katmai National Park.
In 2011, we were awarded contracts from the Exxon Valdez Trustee Council for five years (and up to 15 additional years) to continue monitoring nearshore ecosystems in the Gulf of Alaska in cooperation with the National Park Services Vital Sign program, the University of Alaska, the National Marine Fisheries Service, the Fish and Wildlife Service, and the Kachemak Bay National Estuarine Research Reserve . Our primary objective is to continue monitoring in nearshore areas in the Gulf of Alaska, including study areas within Prince William Sound, Kenai Fjords, Katmai, and Kachemak Bay, following plans initially developed and tested from 2001-2005. We anticipate our monitoring program will eventually form the foundation for a nearshore marine science program that will address questions that arise from monitoring.
Perhaps most important with respect to the goals of our long term monitoring program, the nearshore is the one marine habitat within which it is most likely that we will be able to detect relatively localized sources of change, tease apart human-induced from natural changes, and provide suggestions for policies to reduce human impacts. Because many of the organisms in the nearshore are sessile or have relatively limited home ranges, they can be geographically linked to sources of change with a reasonable degree of accuracy.
Finally, the nearshore is critically important because it was without doubt the habitat most impacted by the 1989 Exxon Valdez oil spill , and as of 2004, was known to be a persistent repository for oil that could be linked to continued injury to species that reside there (especially, sea otters, and harlequin ducks). Thus, monitoring within the nearshore system provides the opportunity to continue to assess progress toward recovery, and to hasten that recovery by identifying and ameliorating other human induced disturbances.
Dean, T. A., and J. L Bodkin. 2006. Sampling protocol for the nearshore restoration and ecosystem monitoring (N-REM) program. Exxon Valdez Restoration Project //0750. Draft Final Report. Exxon Valdez Restoration Office, Anchorage, AK.
Kloecker, K. A., J. L. Bodkin, T. A. Dean and H. A. Coletti. 2009. Monitoring Nearshore Marine Ecosystems in the Gulf of Alaska, poster presented at the 2009 Alaska Marine Science Symposium, Anchorage, AK [PDF file 4.9 mb]
Coletti, H. A., K. A. Kloecker, J. L. Bodkin, and T. A. Dean. 2010. Evaluation of the Southwest Alaska Network Nearshore Monitoring Program: Synthesis, analysis, and insight from the first 5 years. poster presented at the 2010 Alaska Marine Science Symposium, Anchorage, AK [PDF file 2.08 mb]