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GSC scientists were part of an international team of researchers who visited bedrock outcrops on northernmost Ellesmere Island in the summer of 2017. The purpose of the expedition was to document and sample the rocks of Pearya terrane and study the tectonic history of the terrane in order to better reconstruct the past stages of continental drift that formed the Arctic Ocean.
As permafrost thaws in the Arctic, new subsurface pathways open for the transport of groundwater, energy, and solutes. We identify different ways that these subsurface changes are driving observed surface consequences, including the potential for increased contaminant transport, modification to water resources, and enhanced rates of infrastructure (e.g. buildings and roads) damage. Further, as permafrost thaws it allows groundwater to transport carbon, nutrients, and other dissolved constituents from terrestrial to aquatic environments via progressively deeper subsurface flow paths. Cryohydrogeology, the study of groundwater in cold regions, should be included in northern research initiatives to account for this hidden catalyst of environmental and societal change.
Caribou (Rangifer tarandus granti) calf:cow ratios (CCR) computed from composition counts obtained on arctic calving grounds are biased estimators of net calf production (NCP, the product of parturition rate and early calf survival) for sexually-mature females. Sexually-immature 2-year-old females, which are indistinguishable from sexually-mature females without calves, are included in the denominator, thereby biasing the calculated ratio low. This underestimate increases with the proportion of 2-year-old females in the population. We estimated the magnitude of this error with deterministic simulations under three scenarios of calf and yearling annual survival (respectively: low, 60 and 70%; medium, 70 and 80%; high, 80 and 90%) for five levels of unbiased NCP: 20, 40, 60, 80, and 100%. We assumed a survival rate of 90% for both 2-year-old and mature females. For each NCP, we computed numbers of 2-year-old females surviving annually and increased the denominator of CCR accordingly. We then calculated a series of hypothetical “observed” CCRs, which stabilized during the last 6 years of the simulations, and documented the degree to which each 6-year mean CCR differed from the corresponding NCP. For the three calf and yearling survival scenarios, proportional underestimates of NCP by CCR ranged 0.046–0.156, 0.058–0.187, and 0.071–0.216, respectively. Unfortunately, because parturition and survival rates are typically variable (i.e., age distribution is unstable), the magnitude of the error is not predictable without substantial supporting information. We recommend maintaining a sufficient sample of known-age radiocollared females in each herd and implementing a regular relocation schedule during the calving period to obtain unbiased estimates of both parturition rate and NCP.
The western arctic population of King Eiders ( Somateria spectabilis ) has declined by >50% in recent years. A health assessment was conducted for adult King Eiders breeding on the north slope of Alaska, USA, to evaluate body condition ( n =90, 2002–2006) and baseline biochemical and hematologic values ( n =20–30, 2005–2006). Body condition for males and females was excellent. Total protein, calcium, alkaline phosphatase, amylase, and globulin were significantly higher in females than in males, likely because of differences in reproductive physiology. These baseline health data can be used to promote conservation of King Eiders and other closely related species of concern.
We consider use of recoveries of marked birds harvested by hunters, in conjunction with continental harvest estimates, for drawing inferences about continental abundance of a select number of goose species. We review assumptions of this method, a version of the Lincoln?Petersen approach, and consider its utility as a tool for making decisions about harvest management in comparison to current sources of information. Finally, we compare such estimates with existing count data, photographic estimates, or other abundance estimates. In most cases, Lincoln estimates are far higher than abundances assumed or perhaps accepted by many waterfowl biologists and managers. Nevertheless, depending on the geographic scope of inference, we suggest that this approach for abundance estimation of arctic geese may have usefulness for retrospective purposes or to assist with harvest management decisions for some species. Lincoln?s estimates may be as close or closer to truth than count, index, or photo data, and can be used with marking efforts currently in place for estimation of survival and harvest rates. Although there are bias issues associated with estimates of both harvest and harvest rate, some of the latter can be addressed with proper allocation of marks to spatially structured populations if subpopulations show heterogeneity in harvest rates.
A current assessment of oil and gas resources in the Arctic National Wildlife Refuge 1002 area by the U.S. Geological Survey relies upon seismic data, geological mapping of exposures south and west of the assessment area and exploratory wells. Well data assembled for the 41 wells include: well logs, core descriptions and measurements, formation tops, biostratigraphic boundaries, drill-stem tests, casing points, fission-track age dates, vitrinite reflectance, and organic-carbon content. These data are used in the synthesis of all available data and presentation on a well-by-well basis, and extraction of volumetric parameters that are used to assess undiscovered accumulations.
A current assessment of oil and gas resources in the Arctic National Wildlife Refuge (ANWR) 1002 Area by the U.S. Geological Survey relies upon seismic data, geological mapping of exposures south and west of the assessment area, and exploratory wells. Information obtained from wells up to 50 km west and north of ANWR is presented. It is emphasized that the synthesis of well data with other geological and geophysical data provides a quantitative foundation for resource estimates of ANWR.
Long-term monitoring of populations is of paramount importance to understanding responses of organisms to global environmental change and to evaluating whether conservation practices are yielding intended results through time (Wiens 2009). The population status of many shorebird species, the focus of this volume, remain poorly known. Long-distance migrant shorebirds have proven particularly difficult to monitor, in part because of their highly inaccessible regions. As migrant shorebirds travel the length of the hemisphere, the congregate and disperse in ways that vary among species, locations, and years, presenting serious challenges to designing and implementing monitoring programs. Rigorous field and quantitative methods that estimate population size and monitor trends are vitally needed to direct and evaluate effective conservation measures. Many management efforts depend on unbiased population size estimates; for examples, the shorebird conservation plans for both Canada and the United States seek to restore populations to levels calculated for the 1970s based on the best information available from existing surveys. Further, federal wildlife agencies within the United States and Canada have mandates to understand the state of their nations' resources under various conventions for the protection of migratory birds. Accurate estimates of population size are vital statistics for a variety of conservation activities, such as prioritizing species for conservation action and setting management targets. Areas of essential habitat, such as those designated under the Western Hemisphere Shorebird Reserve Network, the Important Bird Areas program of BirdLife Internationals and the National Audubon Society, or Canada's National Wildlife Areas program, are all evaluated on the basis of proportions of species' populations which they contain. The size, and trends in size, of a species' population are considered key information for assessing its vulnerability and subsequent listing under the U.S. Endangered Species Act and the Canadian Species at Risk Act. To meet the need for information on population size and trends, shorebird biologists from Canada and the United States proposed a shared blueprint for shorebird monitoring across the Western Hemisphere in the late 1990s; this effort was undertaken in concert with the development of the Canadian and the U.S. Shorebird Conservation Plans. Soon thereafter, partners in the monitoring effort adopted the name "Program for Regional and International Shorebird Monitoring" (PRISM). Among the primary objectives of PRISM were to estimate the population sizes and trends of breeding North American shorebirds and describe their distributions. PRISM members evaluated ongoing and potential monitoring approached to address 74 taxa (including subspecies) and proposed a combination of arctic and boreal breeding surveys, temperate breeding and non-breeding surveys, and neotropical surveys.
A 1-day, late-summer reconnaissance of the Dietrich River, Alaska, determined species composition and diversity of benthic invertebrates and examined the correlation between stream order and invertebrate distribution. Benthic invertebrates were collected by dip net, drift net, and 10-rock collections, and results were combined for each station. Forty-nine taxa were identified from 5 stations representing stream orders 1 through 5. Aquatic insects comprised 88 percent of all taxa and 97 percent of all individuals from the Dietrich River. Diptera, especially Chironomidae, was the most abundant, followed by Plecoptera. Diamesinae was abundant at the headwaters, decreasing downstream; Orthocladiinae exhibited the reverse distribution pattern. Diversity of collections generally increased downstream. The station collections were compared using coefficients of similarity, cluster analysis, and taxonomy. Collections from adjacent stations were most similar and similarity decreased with increasing distance. The fauna was tentatively divided into zones with characteristic communities: a Diamesinae-Simuliidae fauna in zone I (stream order 1), zone II, a region of transition (orders 2-4), and an Orthocladiinae-Plecoptera-Ephemeroptera fauna in zone III (order 5). The fauna compares closely with that of other arctic streams. Although not conclusive, the benthic invertebrate results are consistent with the hypothesis that stream order is related to lotic biological communities.
Long-term monitoring of populations is of paramount importance to understanding responses oforganisms to global environmental change and to evaluating whether conservation practices are yielding intended results through time (Wiens 2009). The population status of many shorebird species, the focus of this volume, remain poorly known. Long-distance migrant shorebirds have proven particularly difficult to monitor, in part because of their highly migratory nature and ranges that extend into highly inaccessible regions. As migrant shorebirds travel the length of the hemisphere, they congregate and disperse in ways that vary among species, locations, and years, presenting serious challenges to designing and implementing monitoring programs. Rigorous field and quantitative methods that estimate population size and monitor trends are vitally needed to direct and evaluate effective conservation measures. Many management efforts depend on unbiased population size estimates; for example, the shorebird conservation plans for both Canada and the United States seek to restore populations to levels calculated for the 1970s based on the best information available from existing surveys. Further, federal wildlife agencies within the United States and Canada have mandates to understand the state of their nations' resources under various conventions for the protection of migratory birds. Accurate estimates of population size are vital statistics for a variety of conservation activities, such as prioritizing species for conservation action and setting management targets. Areas of essential habitat, such as those designated under the Western Hemisphere Shorebird Reserve Network, the Important Bird Areas program of BirdLife International and the National Audubon Society, or Canada's National Wildlife Areas program, are all evaluated on the basis ofproportions of species' populations which they contain. The size, and trends in size, ofa species' population are considered key information for assessing its vulnerability and subsequent listing under the U.S. Endangered Species Act and the Canadian Species at Risk Act. To meet the need for information on population size and trends, shorebird biologists from Canada and the United States proposed a shared blueprint for shorebird monitoring across the Western Hemisphere in the late 1990s; this effort was undertaken in concert with the development of the Canadian and U.S. Shorebird Conservation Plans (Donaldson et al. 2000, Brown et aL 2001). Soon thereafter, partners in the monitoring effort adopted the name "Program for Regional and International Shorebird Monitoring" (PRISM). Among the primary objectives of PRISM were to estimate the population sizes and trends of breeding North American shorebirds and describe their distributions (Bart et al. 2002). PRISM members evaluated ongoing and potential monitoring approaches to address 74 taxa (including subspecies) and proposed a combination of arctic andboreal breeding surveys, temperate breeding and non-breeding surveys, and neotropical surveys.
Lithostrotion reiseri n. sp. is a cerioid, colonial coral, index fossil for microfossil zones 12-13 (Meramec) in the Lisburne Group in the central and eastern Brooks Range, arctic Alaska.
The North Pacific Rim harbors breeding populations of many unique wildlife resources, of which waterfowl are among the most abundant and taxonomically diverse. Arctic nesting geese in particular are wide-spread in distribution (Figure 1), and though only seasons residents, they have evolved many unique adaptations for breeding in northern latitudes. This diversity has been recognized and managed at many taxonomic and geographic levels (Figure 2). Populations are spatially structured on macro- and micro-geographic scales reflecting taxon-specific migratory tendencies, and breeding and winter site fidelity.
We investigated patterns of winter wolf predation, including prey selection, prey switching, kill rates, carcass utilization, and consumption rates for four wolf packs during three different study periods (March 1989, March 1990, and November 1990) in Gates of the Arctic National Park and Preserve, Alaska. Wolves killed predominantly caribou (165 caribou, seven moose, and five Dall sheep) even when moose and sheep were more abundant. Prey selection varied between study periods. More moose were killed in march 1989, a particularly deep snow year, and more sheep were killed in November 1990 than during other periods. Overall kill rates ranged from 0-8 days/ungulate killed ( x̅ = 2.0, SD = 1.6) and did not vary between study periods. Pack size and species killed explained significant variation in the length of time intervals between kills. Although caribou density varied nearly 40-fold between pack territories, it had little influence on predation characteristics except at low densities, when kill rates may have declined. Caribou distribution had marked effects on wolf predation rate.
This report attempts to review the abundance, status and distribution of natural wild goose populations in the northern hemisphere. The report comprises three parts that 1) summarise key findings from the study and the methodology and analysis applied; 2) contain the individual accounts for each of the 68 populations included in this report; and 3) provide the datasets compiled for this study which will be made accessible on the Arctic Biodiversity Data Service.
Samples of aquatic organisms and water were collected upstream and downstream from leaks and spills of arctic diesel fuel oil into Happy Valley Creek near Sagwon, Alaska. All groups of benthic invertebrates were reduced in abundance at the downstream boundary of the spill area, whereas invertebrates at an upstream site were unaffected.
The Alaska Climate Adaptation Science Center (AK CASC), in partnership with the Aleutian Pribilof Islands Association (APIA), designed the Looking Forward, Looking Back: Building Resilience Today project (hereafter BRT) as a series of trainings and workshops with tribal community leadership and members to collaboratively develop the western science knowledge and Indigenous Knowledge necessary for tribal community adaptation plans. Rather than replicate existing tribally-focused climate adaptation training in Alaska, this pilot project sought to include a range of best practices in education, specifically in climate science and tribal engagement, and builds upon the experience and expertise of the partner teams and communities, the facilitating team, and subject-matter experts. The project had three phases related to its title and structure. The core idea of the Looking Forward, Looking Back: Building Resilience Today project is to include multiple knowledges into adaptation plans that result in resilient communities. Looking Forward refers to the need to plan for our rapidly changing climate by critically considering current and future projected climate and its impacts on the community and Tribe. Looking Back refers to the need for any realistic tribal planning process, and subsequent planning document, to be grounded in Indigenous and local knowledge. The overarching goal of Building Resilience Today is to introduce planning tools that strengthen community capacity to plan for the future, while maintaining important values grounded in the past. Training One: The goal of the first training was to bring the cohort of community members and project team members together to work in teams to gain a common understanding of local climate impacts and longer-term climate projections at the local, regional, statewide, Arctic, and global level.
The Looking Forward Looking Back: Building Resilience Today Training Two is the final training in a series of project engagement events with the partner communities of St. Michael, Kotlik, Kwigillingok, Quinhagak, and Iliamna. Training Two Report provides an overview of the activities and information presented during the training, which took place at the International Arctic Research Center in Fairbanks, Alaska January 28-30, 2020. Training One Report provides an introduction of the project, description of the project structure, and an overview of the activities and information covered in that training. Between Training One and Training Two, the project team traveled to, and worked individually with, each partner community to support the community teams with engaging their leadership and community members on climate issues and planning. This included identifying areas of concern, species of concern, and documenting community observations that could assist in further climate adaptation planning efforts.
This report describes a decision analysis process that was conducted in support of a U.S. Fish and Wildlife Service Environmental Assessment on Arctic grayling ( Thymallus arcticus ) on Red Rocks Lake National Wildlife Refuge in the Centennial Valley, Montana.