This project aimed to enhance spatial planning to accommodate both industrial development and subsistence hunting in a region with rapid climate change. We used eiders, eider hunting, and habitats needed to sustain both as a context for predicting impacts of oil pipeline placement and urban expansion. We initially focused on the nearshore Chukchi Sea, where there were plans for a pipeline across a critical migration corridor for eiders. We characterized long-term variations in ice cover that affected both the eiders’ access to foraging habitats and the ice-edge hunters’ access to the eiders. We found that because ice cover is so variable, there was no particular pipeline placement that would minimize potential exposure of eiders to spilled oil. Knowing alternative feeding areas to be protected in case of a local spill requires tracking the locations of viable feeding areas through time. However, nearshore areas are seldom sampled by oceanographic vessels, so we developed ways to predict locations of high prey density. Long-term data from the similar northern Bering Sea showed that food web types and relative biomass of prey for eiders depended on levels of organic carbon (OC) in the sediments. We then tested the ability of a computer model of bottom currents to predict spatial patterns of sediment OC. In deeper areas with sluggish currents, variations in depth were overwhelmingly the best predictor of sediment OC, whereas in shallower areas, near-bottom currents were the dominant predictor. The models allowed delineation of areas with different food web types associated with different levels of sediment OC over 7 years.  Our findings revealed important opportunities for linking food web models with physical oceanographic models to predict future changes in the locations of critical habitats.

We also investigated trace elements in eiders which are consumed by subsistence hunters. We found there is little threat of trace element contamination to hunters and their families by consuming these birds, except for the livers of spectacled eiders which contained very high levels of Se.

During our project, offshore oil exploration was halted in the Chukchi Sea. However, exploration for oil in coastal tundra increased as did the rate of expansion of the city of Utqiagvik (formerly Barrow). As a result, we extended our work to coastal tundra where sea ducks nest and subsistence hunting for them continues. We characterized the value of different tundra habitats (via studies of behavior and prey availability), and the importance of nearshore vs. tundra habitats to providing nutrients used by eiders in reproduction (via stable isotopes).

Threatened Steller’s Eiders, in particular, have been displaced from previously favored nesting sites by expansion of the city of Utqiagvik. This trend will likely cause increasing conflicts with the U.S. Endangered Species Act, so that sustainable development requires knowing the essential features and extent of potential habitats for the eiders. In other words, is irreplaceable habitat being destroyed, or is there adequate alternative habitat in the region? We are collaborating with researchers from the University of Wisconsin and University of Illinois who have developed detailed landform and vegetation maps of the entire region around Utqiagvik. We have used GPS coordinates of nests found over the last 6 years to map elevations, hydrologic settings, and vegetation of the nest sites of different sea duck species, and to project shifts in availability of those habitats as the tundra thaws with climate warming.

Our stable isotope data indicate that the two larger-bodied sea ducks obtain nutrients for egg production from both local tundra wetlands and from marine habitats used before arrival. The two smaller-bodied sea ducks rely almost entirely on foods from tundra wetlands. We have also measured the birds’ foraging behavior and the availability of invertebrate prey in the different wetland types. Wetland types used by the birds after arrival (shallow wetlands dominated by emergent grasses and sedges) are declining in availability with changing climate. Although a number of studies have documented changes in the numbers and sizes of tundra ponds with climate change, our work is the first to provide details of the trophic consequences for dominant vertebrate consumers and their invertebrate prey.

Native people are often conflicted about tradeoffs between economic development and preserving their subsistence way of life.  Over 3 years we conducted a series of workshops in the village of Wainwright to introduce structured decision-making as a means of clarifying alternatives and reaching consensus. The participants said that the experience was quite useful.

We have collaborated closely with the U.S. Fish and Wildlife Service on their long-term Eider Project. Every year, volunteers from the local high school are trained to assist in foot surveys of this very large area to search for nests, count lemmings, and capture nesting eiders. Two graduate students on this project were instrumental in training and supervising these mostly Alaska Native students.

Last Modified: 11/26/2019
Modified by: James R Lovvorn