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At least 1,765 records · Page 98Linked to original sources
USGS2020

Looking forward, looking back: Building resilience today community report: St. Michael, AK

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 (hereafter ‘BRT’) project as a series of trainings and workshops with tribal community leadership and members. The overarching goal of the project was to collaboratively develop the Indigenous knowledge and western science knowledge for adaptation planning. We worked with five community teams consisting of up to four leaders from communities that chose to participate in the project: Iliamna, Kotlik, Kwigillingok, Quinhagak, and St. Michael. Community teams were developed through the application process and the project duration. Community teams were encouraged to have involvement from multiple governing bodies within the community that could include the Tribal Council, city government, and village corpora- tion. The project title, with its references to the future (Looking Forward), past (Looking Back), and present (Building Resilience Today), refers to the idea that adaptation planning relies on all three perspectives. Equally important, how- ever, is the dialogue to exchange past and present information, context, and what we expect in the future. According- ly, two training sessions held at the International Arctic Research Center in Fairbanks, Alaska at the beginning and near the end of the project were developed to provide community team interaction with each other and with university and federal science partners. The project team also traveled to the partner communities and held a series of onsite events with community members to document locally-relevant information and share climate science tailored to the needs and conditions of each community. This report represents the community information shared during those onsite events. The Meeting Announcement (page 5) shows the date and description of the outreach events. The purpose of these events was to: 1) facilitate mapping of a Traditional Use Area to refine an area for climate pro- jections; 2) construct current and past seasonal Subsistence Calendars to identify important species and times of the year; 3) document Indigenous and local knowledge from current community members about environmental changes they have observed over their lifetimes; and 4) assist with documenting what the community perceived to be climate-related issues through photos and interviews. The agenda of the visits was co-produced with the commu- nity team. In each community, the community team and the project team co-hosted an open-to-the-public meeting and met with various groups. The community team advertised the meetings by posting community fliers, making announcements on the community radio, and reaching out to individuals that would contribute to the engagement discussions. Each community meeting focused on activities to develop seasonal Subsistence Calendars, map Tradition- al Use Areas, and document observed environmental changes. Community members spent time at stations dedicated to each of these activities working with project team members. The project team also met with various groups of indi- viduals that included village corporation, tribal council, and city representatives where additional information about observed environmental changes was gathered. This community report presents some of the information developed in these activities.

Alaska↗
USGS2020

Looking forward, looking back: Building resilience today community report: Kwigillingok, AK

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 (hereafter ‘BRT’) project as a series of trainings and workshops with tribal community leadership and members. The overarching goal of the project was to collaboratively develop the Indigenous knowledge and western science knowledge for adaptation planning. We worked with five community teams consisting of up to four leaders from communities that chose to participate in the project: Iliamna, Kotlik, Kwigillingok, Quinhagak, and St. Michael. Community teams were developed through the application process and the project duration. Community teams were encouraged to have involvement from multiple governing bodies within the community that could include the Tribal Council, the city government, and the village corporation. The project title, with its references to the future (Looking Forward), past (Looking Back), and present (Building Resilience Today), refers to the idea that adaptation planning relies on all three perspectives. Equally import- ant, however, is the dialogue to exchange past and present information, context, and what we expect in the future. Ac- cordingly, two training sessions held at the International Arctic Research Center in Fairbanks, Alaska at the beginning and near the end of the project were developed to provide community team interaction with each other and with university and federal science partners. The project team also traveled to the partner communities and held a series of onsite events with community members to document locally-relevant information and share climate science tailored to the needs and conditions of each community. This report represents the community information shared during those onsite events. The Meeting Announcement (page 5) shows the date and description of the outreach events. The purpose of these events was to: 1) facilitate mapping of a Traditional Use Area to refine an area for climate pro- jections; 2) construct current and past seasonal Subsistence Calendars to identify important species and times of the year; 3) document Indigenous and local knowledge from current community members about environmental changes they have observed over their lifetimes; and 4) assist with documenting what the community perceived to be climate-related issues through photos and interviews. The agenda of the visits was co-produced with the commu- nity team. In each community, the community team and the project team co-hosted an open-to-the-public meeting and met with various groups. The community team advertised the meetings by posting community fliers, making announcements on the community radio, and reaching out to individuals that would contribute to the engagement discussions. Each community meeting focused on activities to develop seasonal Subsistence Calendars, map Tradition- al Use Areas, and document observed environmental changes. Community members spent time at stations dedicated to each of these activities working with project team members. The project team also met with various groups of indi- viduals that included village corporation, tribal council, and city representatives where additional information about observed environmental changes was gathered. This community report presents some of the information developed in these activities.

Alaska↗
USGS2020

Looking forward, looking back: Building resilience today community report: Kotlik, AK

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 (hereafter ‘BRT’) project as a series of trainings and workshops with tribal community leadership and members. The overarching goal of the project was to collaboratively develop the Indigenous knowledge and western science knowledge for adaptation planning. We worked with five community teams consisting of up to four leaders from communities that chose to participate in the project: Iliamna, Kotlik, Kwigillingok, Quinhagak, and St. Michael. Community teams were developed through the application process and the project duration. Community teams were encouraged to have involvement from multiple governing bodies within the community that could include the Tribal Council, the city governments, and the village corporations. The project title, with its references to the future (Looking Forward), past (Looking Back), and present (Building Resil- ience Today), refers to the idea that adaptation planning relies on all three perspectives. Equally important, however, is the dialogue to exchange past and present information, context, and what we expect in the future. Accordingly, two training sessions held at the International Arctic Research Center in Fairbanks, Alaska at the beginning and near the end of the project were developed to provide community team interaction with each other and with university and feder- al science partners. The project team also traveled to the partner communities and held a series of onsite events with community members to document locally-relevant information and share climate science tailored to the needs and conditions of each community. This report represents the community information shared during those onsite events. The Meeting Announcement (page 5) shows the date and description of the outreach events. The purpose of these events was to: 1) facilitate mapping of a Traditional Use Area to refine an area for climate projec- tions; 2) construct current and past seasonal Subsistence Calendars to identify important species and times of the year; 3) document Indigenous and local knowledge from current community members about environmental changes they have observed over their lifetimes; and 4) assist with documenting what the community perceived to be climate-relat- ed issues through photos and interviews. The agenda of the visits was co-produced with the community team. In each community, the community team and the project team co-hosted an open-to-the-public meeting and met with various groups. The community team advertised the meetings by posting community fliers, making announcements on the community radio, and reaching out to individuals that would contribute to the engagement discussions. Each commu- nity meeting focused on activities to develop seasonal Subsistence Calendars, map Traditional Use Areas, and document observed environmental changes. Community members spent time at stations dedicated to each of these activities working with project team members. The project team also met with various groups of individuals that included village corporation, tribal council, and city representatives where additional information about observed environmental chang- es was gathered. This community report presents some of the information developed in these activities.

Alaska↗
USGS2022

Appendix 7: Application of joint dynamic species distribution models to at-sea survey data for seabirds in the Bering Strait and Chukchi Sea

Mitigating risk to migratory birds from energy development requires information on the distribution and abundance of seabirds in offshore waters. Seabirds are highly mobile, with species-specific seasonal migrations that result in variable patterns of distribution in space and time. In remote offshore marine areas, obtaining useful and current information on resources is difficult to achieve and maintain, both fiscally and logistically, necessitating collaborative effort (Danielson et al. 2022). We used seabird at-sea survey data (2007-2021) and new modeling techniques to develop spatio-temporal models of seasonal abundance and distribution of species in waters of the Pacific Arctic. For six species groups selected as model test cases, we identified fine-scale distributions for each year, using data collected during summer to early fall (June through September). Our approach uses the best available data and can be updated as new data are generated, providing up-to-date information for regions with existing or potential future oil and gas development.

Beaufort Sea, Bering Sea, Chukchi Sea↗
USGS2024

Thermo-hydrologic processes governing supra-permafrost talik dynamics in discontinuous permafrost near Umiujaq (Québec, Canada)

Widespread supra-permafrost talik formation is currently recognized as a critical mechanism that could accelerate permafrost thaw in the Arctic (e.g., Connon et al. 2018; Farquharson et al. 2022). However, the trajectory of permafrost dynamics following talik formation may prove difficult to predict. Physically-based cryohydrogeologic models provide a powerful tool for understanding processes and factors controlling talik dynamics and, ultimately, how permafrost will respond to climate change. Such models are typically used to represent multiple non-linear processes relevant for groundwater systems in cold regions, such as coupled heat and groundwater movement, including freeze-thaw dynamics and the effects on the surface energy balance and the subsurface thermal and hydraulic properties (Lamontagne-Hallé et al. 2020). Though cryohydrogeologic modeling advances have been made in simulating talik dynamics, few applications have been tested against robust long-term hydrometeorological and subsurface observations.

Quebec↗
USGS2024

A history of cryohydrogeology modeling and recent advancements through the integration of solute transport

Groundwater flow systems and permafrost are interrelated because permafrost thaw enhances permeability, while groundwater flow can advect heat and accelerate permafrost thaw (McKenzie et al. 2021). Given amplified climate change in cold regions, there is renewed interest in ‘cryohydrogeology’, the study of groundwater in cold regions. Many data-driven studies have shown that permafrost thaw is leading to activated aquifers and increased baseflow across the pan-Arctic region (e.g. Walvoord and Striegl 2007, Evans et al. 2020). Empirical evidence of a subsurface ‘replumbing’ (Walvoord and Kurylyk 2016) in permafrost regions raises questions about the fate of sequestered contaminants in the North (Langer et al. 2023). We will discuss the history of and emerging opportunities in cryohydrogeological modeling, with a focus on recent contaminant transport modeling.

Conference Paper↗
USGS2024

Perspectives on equitable co-production workshop report

The co-production of knowledge is increasingly recognized as an approach to conducting research intended to achieve a societal impact. In this study, we used a broad definition of co-production, defining it as “a process that brings together diverse groups to iteratively create new knowledge and practices (1).” However, co-production has been defined and conceptualized in a variety of ways (2,3), across multiple domains, including public administration, conservation, health, education, and climate change. Theoretical definitions have been introduced by scholars like Jasanoff (4) and Ostrom (5), but definitions can also be grounded in practice (6). For example, unique definitions of co-production have been advanced for work with Arctic Indigenous Peoples (7), in the context of resource management (8), and for a specific program (9). Other similar processes of engagement, such as community-based participatory research (10), action research (11), civic science (12), community science (13), and post-normal science (14) may have overlap with the concept of co-production and have been used to describe similar processes of collaboration. These distinctions and varying definitions have been discussed extensively elsewhere (see Mach et al. 2020, Wyborn et al. 2019). In the context of co-production, power plays a crucial role in shaping interactions and outcomes. Some scholars and practitioners explicitly consider power dynamics as a central element in their definitions of co-production, recognizing how power imbalances can affect participation, decision-making, and the distribution of benefits. Others, however, might not emphasize power as prominently, focusing more on the collaborative aspects without explicitly addressing the underlying power structures. This leads to divergent objectives and priorities among projects claiming to be co-produced (2,3, 6). Chambers and colleagues (2) discussed how co-production projects in the context of sustainability usually emphasize one or more of six different goals, including: researching solutions, empowering voices, brokering power, reframing power, navigating differences, and reframing agency. Because power dynamics are inherent in co-production (15), equity dimensions should be considered in these definitions and conceptualizations. Yet, in the context of government or academically led climate change research and programs, equity is a relatively new focus, even among programs that have been engaging a co-production approach for decades (9). Alternatively, in some recent work the concept of equity in co-production is explicit, but it has only been considered in a limited context (7). Here, we present a discussion about co-production that is informed by research, practice, and community perspectives across partnerships from a range of regions and topics. We are specifically interested in how different actors in these projects think about equity and work towards more equitable approaches in the context of their co-production work. This understanding is needed, as the federal government has increasingly focused on co-production approaches in the design of their programs and funding calls, and most recently the Biden administration has called on federal agencies to more intentionally center equity for underserved groups of people in their work (16). Furthermore, with the Biden administration’s focus on environmental and climate justice, the opportunity for researchers and their societal partners to engage in co-production is expanding. Numerous programs within federal agencies have embraced a co-production approach, such as the National Oceanic and Atmospheric Administration (NOAA) Climate Adaptation Partnerships (CAP; formerly called the Regional Integrated Sciences and Assessments or RISA program) (9,17), Department of the Interior (DOI) Climate Adaptation Science Centers (CASCs)(18), and the US Department of Agriculture (USDA) Climate Hubs. However, the actual implementation of co-production processes varies significantly (1,19), with multiple implications for the design of equitable partnerships. Researchers, their partners, and funders have frequently cited many tensions and challenges in the successful implementation of co-production, including higher resource demands and few systemic structures for support (20). Practically implementing co-production, especially with people who have been underrepresented in or historically excluded from research activities, must consider fairness and the accessibility of co-production processes. While co-production is often cited as important for environmental governance, issues like power and equity are infrequently addressed (15). To explore this topic, we identified and studied three projects that centered on equity in co-production from three federal climate programs (CASC, CAP, USDA Climate Hubs) in three different regions of the U.S. (Alaska, Northeast, Southeast). We aimed to identify consensus or divergence in perspectives related to equitable co-production processes to elevate effective practices and link co-production research and practice. Findings from interviews and a survey (explained further in Akerlof et al., 2023) informed a twoday hybrid workshop involving participants from the three case studies, as well as individuals representing research, governmental, non-governmental, and community organizations across the United States. Participants also included scholars of co-production, program coordinators, and people who participated in co-production projects on behalf of their communities. Several boundary spanners, those practitioners who work at the intersection of the production and use of science (21,22), also attended the workshop. The goals of the workshop were to discuss and build on what was learned from the three case studies, discuss the three distinct perspectives on equitable co-production that emerged from the pre-workshop research, and draft a framework for equitable co-production processes. During the workshop, participants considered the three perspectives on equitable co-production, defining equitable co-production for each and discussing the practical implications of each, including barriers and priorities for overcoming them. We aimed to address the question: How can federal climate programs support equitable co-production processes?

Report↗
USGS2023

Red Knot stopover population size and migration ecology at Delaware Bay, USA, 2023

Red Knots ( Calidris canutus rufa ) stop at Delaware Bay on the mid-Atlantic coast of North America during northward migration to feed on eggs of horseshoe crabs ( Limulus polyphemus ). We conducted a mark-recapture-resight investigation to estimate the passage population of Red Knots at Delaware Bay in 2023. We used a Bayesian analysis of a Jolly-Seber model, which accounts for turnover in the population and the probability of detection during surveys. The 2023 passage population size was estimated at 39,361 (95% credible interval: 33,724–47,556). Although there is broad overlap in the credible intervals for population estimates from 2020–2023, the population estimate for 2023 was below 40,000 birds for only the second time since 2011. Horseshoe crabs have been harvested for use as bait in eel ( Anguilla rostrata ) and whelk ( Busycon ) fisheries since at least 1990. In the late 1990s and early 2000s, the number of Red Knots counted during aerial surveys at Delaware Bay declined from ~50,000 to ~13,000 and some avian conservation biologists hypothesized that horseshoe crab harvest levels in the 1990s prevented sufficient refueling for successful migration to the Arctic breeding grounds, reproduction, and survival for the remainder of the annual cycle. Since 2013, the harvest of horseshoe crabs in the Delaware Bay region has been managed using an Adaptive Resource Management (ARM) framework. The objective of the ARM framework is to manage sustainable harvest of Delaware Bay horseshoe crabs while maintaining ecosystem integrity and supporting Red Knot recovery with adequate stopover habitat for Red Knots and other migrating shorebirds. For annual harvest recommendations, the ARM framework requires annual estimates of horseshoe crab population size and the Red Knot stopover population size. The 2023 population size estimate will inform harvest recommendations in the next management cycle for decision making by the Atlantic States Marine Fisheries Commission.

Delaware, New Jersey↗
USGS2025

Pleistocene porcupine (Erethizontidae) records in arid southwestern North America and comparisons with the modern distribution of Erethizon dorsatum in southern California and Arizona

he North American porcupine ( Erethizon dorsatum ) is widely distributed throughout many ecosystems on the continent from northern Mexico to the Arctic Ocean, except for the southeastern portion of the United States. Habi­tats include the arid Desert Southwest region where modern records are generally sparse. The paleogeographic range in the Desert Southwest is not unlike the modern distribution of Erethizon , with some exceptions. Although there are early Pleistocene records of Erethizon for southern California, no late Pleistocene records (Rancholabrean North American Land Mammal Age [NALMA]) are known for Imperial, Inyo, Riverside, or San Bernardino Counties in southern California or in Mexico. This is surprising given late-Pleistocene records in Arizona, Nevada, and New Mexico and modern records from southern California and Mexico. Pleistocene habitats for porcupines were similar to those occupied today, just at different elevations due to differing climates. Modern preferred habitats in the Desert Southwest include conifer-clad high-elevation areas and associated pinyon pine / juniper belts, and occasionally riparian corridors in desert environments. The overall rarity of porcupines today in arid parts of the Desert Southwest is likely due to the combination of increasing aridity in the region during the Holocene, past persecution by humans, and increasing predator populations.

Arizona, California↗
USGS1998

Great Lakes

The Great Lakes region, as defined here, includes the Great Lakes and their drainage basins in Minnesota, Wisconsin, Illinois, Indiana, Ohio, Pennsylvania, and New York. The region also includes the portions of Minnesota, Wisconsin, and the 21 northernmost counties of Illinois that lie in the Mississippi River drainage basin, outside the floodplain of the river. The region spans about 9º of latitude and 20º of longitude and lies roughly halfway between the equator and the North Pole in a lowland corridor that extends from the Gulf of Mexico to the Arctic Ocean. The Great Lakes are the most prominent natural feature of the region (Fig. 1). They have a combined surface area of about 245,000 square kilometers and are among the largest, deepest lakes in the world. They are the largest single aggregation of fresh water on the planet (excluding the polar ice caps) and are the only glacial feature on Earth visible from the surface of the moon (The Nature Conservancy 1994a). The Great Lakes moderate the region’s climate, which presently ranges from subarctic in the north to humid continental warm in the south (Fig. 2), reflecting the movement of major weather masses from the north and south (U.S. Department of the Interior 1970; Eichenlaub 1979). The lakes act as heat sinks in summer and heat sources in winter and are major reservoirs that help humidify much of the region. They also create local precipitation belts in areas where air masses are pushed across the lakes by prevailing winds, pick up moisture from the lake surface, and then drop that moisture over land on the other side of the lake. The mean annual frost-free period—a general measure of the growing-season length for plants and some cold-blooded animals—varies from 60 days at higher elevations in the north to 160 days in lakeshore areas in the south. The climate influences the general distribution of wild plants and animals in the region and also influences the activities and distribution of the human population. The wild plants and animals and the natural systems that support them in the Great Lakes region are valuable resources of considerable local, regional, and national interest. They are also, in part, transboundary resources that we share with our Canadian neighbors to the north. The way these resources are changing over time is inadequately known and is a cause for concern for resource users and for those charged with managing and protecting these unique and valuable resources. This chapter describes the wild plants and animals and the systems that support them in the Great Lakes region; addresses their condition; and points out the gaps in our knowledge about them that, if filled, would aid in their conservation and appropriate use.

Illinois, Indiana, Minnesota, New York, Ohio, Penn↗
USGS2003

Wolf-prey relations

As I (L.D. MECH) watched from a small ski plane while fifteen wolves surrounded a moose on snowy Isle Royale, I had no idea this encounter would typify observations I would make during 40 more years of studying wolf-prey relations. My usual routine while observing wolves hunting was to have my pilot keep circling broadly over the scene so I could watch the wolves’ attacks without disturbing any of the animals. Only this time there was no attack. The moose held the wolves at bay for about 5 minutes (fig. 5.1), and then the pack left. From this observation and many others of wolves hunting moose, deer, caribou, muskoxen, bison, elk, and even arctic hares, we have come to view the wolf as a highly discerning hunter, a predator that can quickly judge the cost/benefit ratio of attacking its prey. A successful attack, and the wolf can feed for days. One miscalculation, however, and the animal could be badly injured or killed. Thus wolves generally kill prey that, while not always on their last legs, tend to be less fit than the conspecifics and thus closer to death. The moose that the fifteen wolves surrounded had not been in this category, so when the wolves realized it, they gave up. This is most often the case when wolves hunt.

Book chapter↗
USGS1988

Polar Bear

Polar bears are long-lived, late-maturing carnivores that have relatively low rates of reproduction and natural mortality. Their populations are susceptible to disturbance from human activities, such as the exploration and development of mineral resources or hunting. Polar bear populations have been an important renewable resource available to coastal communities throughout the Arctic for thousands of years.

Report↗
USGS2004

Waterfowl migration on Klamath Basin National Wildlife Refuges 1953-2001

The Klamath Basin National Wildlife Refuge (NWR) complex, located in northeastern California and southern Oregon, is situated on a major Pacific Flyway migration corridor connecting waterfowl breeding grounds in the north with major wintering grounds in California and Mexico. The complex comprises five waterfowl refuges including Lower Klamath NWR, Tule Lake NWR, Upper Klamath NWR, Klamath Marsh NWR, and Clear Lake NWR, and one bald eagle refuge, Bear Valley NWR. Lower Klamath and Tule Lake NWRs are the largest refuges in the complex; historically, they supported some of the greatest autumn and spring concentrations of migrating waterfowl in North America. Starting in 1953, standardized waterfowl surveys from small aircraft have been conducted in autumn through spring. This report summarizes waterfowl migration activity (i.e., abundance, species composition, distribution on refuges, and chronology) over four time periods—the long-term (1953-2001), early (1953-76), recent (1977-2001), and the most recent (1998-2001)—to describe changing patterns of migration on Klamath Basin refuges from autumn 1953 to spring 2001. Over the long term, waterfowl abundance (birds per day) on the refuge complex averaged about 1.0 million in autumn and about 360,000 in spring. A record peak count of 5.8 million waterfowl was recorded September 24-25, 1958. Average abundance of autumn staging waterfowl for the refuge complex, after reaching record levels in the 1950s and early 1960s, began a decline that lasted until the 1980s. A gradual recovery occurred during the 1990s, but autumn abundance has not recovered to pre-1970 levels. In contrast to autumn, average spring abundance was generally lower in the early decades but has gradually increased through the 1990s, particularly on Lower Klamath NWR. Dabbling ducks represented an average of 68% of all waterfowl in autumn and 55% in spring for the long term. Northern pintail ( Anas acuta ) was dominant, representing 62% of all dabblers in autumn and 51% in spring. A significant decline in pintail abundance starting in the late 1950s altered waterfowl composition on Klamath Basin refuges. As pintail declined, other species such as mallard ( Anas platyrhynchos ) and green-winged teal ( Anas crecca ) increased in abundance. Although Arctic nesting geese, including white-fronted ( Anser albifrons ), cackling Canada ( Branta canadensis minima ), white geese (lesser snow [ Chen caerulescens caerulescens ], and Ross’s [ Chen rossii ]) have become less prominent in recent decades, they reached an historically high abundance during autumn in the 1960s and 1970s, particularly on Tule Lake NWR. Tule Lake NWR supported the highest average autumn waterfowl populations until surpassed by Lower Klamath NWR around 1980. During the recent period (1977-2001), Lower Klamath NWR accounted for 60% of all waterfowl using the refuge complex in autumn and 61% in spring. Habitat diversity and wetland productivity contributed to its greater waterfowl abundance. Tule Lake NWR supported the most geese over the long term, 79% in autumn and 66% in spring; however, total waterfowl abundance on this refuge in autumn has been in decline, likely because of reduced diversity and productivity of sumps in the refuge. Upper Klamath, Klamath Marsh, and Clear Lake NWRs accounted for less than 8% of total waterfowl use in autumn and spring but provided diverse habitats for migrants. Waterfowl use-days on Klamath Basin refuges typically peaked in mid-autumn, decreased as migrants passed through the basin, and then reached a lesser peak during spring passage. Waterfowl abundance reached a pronounced peak in autumn during the early period (1953-76), but spring peak buildup was much less pronounced. For the recent period the autumn peak was more subdued. Waterfowl abundance, species composition, and distribution on Klamath Basin refuges have fluctuated over the decades and have been influenced by events such as productivity on breeding grounds and habitat conditions on wintering grounds that cause shifts in migration patterns. A major challenge for the future appears to be the availability of adequate water for wetland management on Klamath Basin refuges.

California, Oregon↗
USGS1985

Habitat Suitability Index Models: Lesser snow goose (wintering)

The lesser snow goose may have the largest population of any goose in the world (Cooch 1958; Kerbes 1975; Ogilvie 1978). Its arctic breeding range has greatly expanded since the mid-1950's (Bellrose 1976). In the United States, it normally ranks behind only the Canada goose (Branta canadensis) in population size (Bellrose 1976; Owen 1980) and in harvest (Carney et al. 1981, 1982). Because up to 70% of the geese harvested annually by hunters in Texas and Louisiana are lesser snow geese (Carney et al , 1981), its importance as a waterfowl species of the Gulf of Mexico coast cannot be overemphasized. Surveys taken in the Central and Mississippi Flyways from 1955 to 1975 have shown an upward trend in the number of wintering snow geese (Bellrose 1976). On the wintering grounds snow geese tend to remain in large, very conspicuous flocks that please both hunters and non-consumptive viewers of wildlife.

FWS/OBS↗
USGS2018

Deglaciation and postglacial vegetation history of the West Mountains, west-central Idaho, U.S.A.

The West Mountains, west-central Idaho, were deglaciated before ca. 11,500 BP, as indicated by radiocarbon ages and Glacier Peak tephra, at several sites in cirques. Pollen analysis of a sediment core, and plant macrofossils from sediments recovered from the cirque at the head of Van Wyck Creek, indicate that a closed spruce-pine forest surrounded the site from ca. 11,500 to 9800 BP. Early in this period, spruce (probably krummholz) was already growing near the present-day altitudinal limit of large upright spruce. Hence, the climate during this period was significantly warmer than before 11,500 BP. Between ca. 9800 and 3200 BP the climate was warmer and drier than present. Pollen data indicate that from ca. 9300 to the time of Mazama tephra deposition (ca. 6700 BP), the climate was warmer and drier than at any time since 11,500 BP. From ca. 6700 to 3200 BP there was a small decrease in temperature with a minor increase in effective moisture. Beginning ca. 3200 BP, the climate was characterized by cooler temperatures and more mesic conditions. Modern plant communities were established by ca. 1500 BP.

Idaho↗
USGS2018

Periphyton dynamics in a subalpine mountain stream during winter

We conducted two experiments to determine the activity of and factors which control periphyton during winter in Stevensville Brook, Vermont. The first experiment during winter/spring 1994 examined the effect of a 300 to 450% difference in light and doubling of flow (low and high light, slow and fast flow) on periphyton chlorophyll a (chl a ) and ash-free dry mass (AFDM) from stream rocks and artificial substrata. A second experiment was performed to determine whether periphyton was nitrogen or phosphorus limited. In addition, stream water was sampled during fall/winter 1994/95 for nitrate (NO 3 ), ammonia (NH 4 ), soluble reactive phosphorus (SRP), and total phosphorus (TP) to determine the availability of nutrients in Stevensville Brook. Increases of up to 250% for AFDM and 600% for chl a during the first study indicated robust activity throughout the winter despite low temperatures and light. Flow had a negative effect and sampling date was found to have a significant effect on periphyton biomass (chl a and AFDM) while light was found to influence increases in AFDM on clay tiles only. Water analyses showed that SRP was less than 0.001 mg L −1 , NH 4 and TP were low and often undetectable, and NO 3 remained at about 0.20 mg L −1 . Results from the nutrient enrichment experiment showed a significant response of chl a to P but not N and no response of AFDM to enrichment with either N or P. In Stevensville Brook during winter, the algal community, as represented by the chl a concentration, is predominantly controlled by phosphorus concentrations and is influenced to a lesser extent by flow; the periphyton community as a whole, represented by AFDM, is controlled mostly by stream flow and light.

Vermont↗
USGS2018

Lake levels in a discontinuous permafrost landscape: Late Holocene variations inferred from sediment oxygen isotopes, Yukon Flats, Alaska

During recent decades, lake levels in the Yukon Flats region of interior Alaska have fluctuated dramatically. However, prior to recorded observations, no data are available to indicate if similar or more extreme variations occurred during past centuries and millennia. This study explores the history of Yukon Flats lake origins and lake levels for the past approximately 5,500 years from sediment analyses guided by previous work on permafrost extent, thermokarst, and modern isotope hydrology. Sediments dated by 210 Pb and AMS radiocarbon indicate stable chronologies following initial lake initiation. Subsequent lithology is autochthonous, and oxygen isotope ratios of endogenic carbonate reflect lake level change at multiple time scales. Sediment results indicate high lake levels between approximately 4000 and 1850 cal yr BP, which is interpreted to reflect wetter-than-modern conditions. Lower lake levels with short-lived high stands during the past approximately 800 years reflect generally arid conditions with brief wet intervals similar to the region’s moisture regime today. The millennial trend is one of increasing aridity and corresponds closely with fire reconstructions and regional paleoclimatic trends. We conclude that high-magnitude lake-level fluctuations and decadal scale trends occurred before the observational period and are persistent hydroclimatic features of the Yukon Flats region.

Alaska↗
USGS2019

Glacier recession since the Little Ice Age: Implications for water storage in a Rocky Mountain landscape

Glacial ice is a significant influence on local climate, hydrology, vegetation, and wildlife. We mapped a complete set of glacier areas from the Little Ice Age (LIA) using very high-resolution satellite imagery (30-cm) within Glacier National Park, a region that encompasses over 400,000 hectares. We measured glacier change across the park using LIA glacier area as a baseline and used this to estimate change in glacier area and volume over time. An estimated 146 glaciers existed within the current boundaries of Glacier National Park during the LIA. By 2005, only 51 (35%) persisted. Nearly 90% of LIA glaciers had lost 50% of their area by 2005. This decrease in glacier area equates to an estimated loss of ice volume of 1.52 km3, or 1.37 km3 of water storage, roughly equivalent to 40% of Lake McDonald, the largest lake in the park. Understanding rates of deglaciation and implications for water storage and use can assist local resource managers and downstream communities in planning for change.

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