National Wildlife Refuge Research Articles

LOUSY ASSOCIATIONS: SUCKING LICE (PHTHIRAPTERA: ANOPLURA) PARASITIZING RODENTS AND LAGOMORPHS IN THE DESERT NATIONAL WILDLIFE REFUGE, NEVADA.

Seventy of 190 (37%) mammals, representing 14 rodent and 2 lagomorph species examined in the Desert National Wildlife Refuge in southern Nevada, were parasitized by sucking lice (Phthiraptera: Anoplura). Twelve species of sucking lice (5 species of Hoplopleruridae, 7 species of Polyplacidae) were recorded. Nine of these louse species (Hoplopleura difficilis, Hoplopleura ferrisi, Hoplopleura onychomydis, Hoplopleura reithrodontomyis, Fahrenholzia reducta, Haemodipsus setoni, Neohaematopinus citellinus, Neohaematopinus neotomae, and Polyplax auricularis) are reported from Nevada for the first time, and Po. auricularis is recorded from Peromyscus eremicus (cactus deermouse) for the first time. Infestation prevalences, mean intensities, sex ratios, host associations, and host specificity are presented and discussed for each louse-host interaction.

Quantifying Post‐Colonial Peat Carbon Loss From a Drained Forested Peatland, Great Dismal Swamp National Wildlife Refuge, USA

AbstractPeatland carbon storage is increasingly threatened by the combination of land‐use change and climate variability, though carbon losses from land‐use changes that span centuries are difficult to quantify, particularly in systems where little undisturbed area remains. Here we use a combination of vegetation change, fire history, and calculations of excess ash mass to quantify carbon loss in the Great Dismal Swamp National Wildlife Refuge (GDS NWR), USA, a highly impacted oligotrophic temperate peat swamp. Our results indicate that ditch construction that began in the Colonial Era in the late 1700s and continued into the mid‐20th century across the swamp resulted in shifts from cypress‐tupelo swamps to a combination of maple‐gum and pine pocosin forests, consistent with drying surface conditions. Two large smoldering fires (2008, 2011) that were exacerbated by surface drainage, shifted vegetation from swamp to marsh, consumed peat over 25 km2, and caused losses of 1.05–1.34 Tg C due to peat burning. Across the Refuge as a whole, up to 48.2 Tg C has been lost to peat oxidation since ditch construction. Both stocks and rates of carbon loss remain higher than post‐disturbance accumulation across most of GDS NWR, suggesting that existing efforts to block drainages to elevate water tables may not be enough to offset carbon losses. Rewetting heavily impacted surface peats may reduce peat oxidation and carbon loss, and shift vegetation toward hydrologic conditions preferred by pre‐disturbance cypress‐tupelo swamps.

From Securing the Border to Securing Nature: Homeland Security as an Emerging Environmental Actor in the U.S.–Mexico Borderlands

Hundreds of miles of barriers span the U.S.–Mexico border, not only blocking the migration of people, but also crisscrossing National Parks and Wildlife Refuges and bifurcating important wildlife corridors in the process. Despite their location within federally protected places, the past and present construction of these barriers has progressed unencumbered by federal oversight given the waiver of dozens of environmental regulations. This shift in regulation amid increased border militarization has not been fully evaluated for its environmental effects, as federal conservation agencies tasked with managing public borderlands are increasingly prohibited from studying how barriers will affect the landscape in the long term. This research examines how the state is shaping environmental governance and knowledge politics in the U.S.–Mexico borderlands, an environmentally significant and hyperpoliticized region integral to the maintenance of the United States as an imperial border-making institution. Bringing together theories on political ecologies of the settler colonial state with the racialization of nature, this article demonstrates how (1) the Department of Homeland Security has emerged as an environmental actor produced through a reconfiguration of settler state power; (2) knowledge claims about the environment are produced in ways that elide the ecological consequences of border barriers; and (3) racialized discourses of migrants are codified in environmental governing documents that support increased border militarization. I conclude with a discussion of how settler colonial technologies of environmental governance create new geographies of militarization and conservation in federally protected places along the U.S.–Mexico border.

Highly pathogenic avian influenza A virus subtype H5N1 (clade 2.3.4.4b) isolated from a natural protected area in Peru.

The panzootic caused by H5N1 avian influenza viruses is a high concern for wild birds' conservation and the study of spillover events into mammals. The near coding-complete genome of H5N1 clade 2.3.3.4b sequencing in the Miseq Illumina platform was performed from a bird located in Pantanos of Villa National Wildlife Refuge.

Trends in American Alligator Pods in Arthur R. Marshall Loxahatchee National Wildlife Refuge

Abstract American alligators are an important component of the Greater Everglades, serving as ecosystem engineers, predator, and prey and are tightly tied to water depth patterns. Because of their importance to ecosystem function and link to hydrology, American alligators are an ecological indicator for Everglades restoration. I used data from fall nighttime spotlight surveys of American alligators in the Arthur R. Marshall Loxahatchee National Wildlife Refuge, Florida, to describe the trend in number of hatchling pods from 1998 to 2021 and relate that trend to hydrologic parameters hypothesized to influence American alligator production. I used an information-theoretic approach to evaluate 14 models created from combinations of year of observation and three hydrologic variables: average and range in water depth from 16 April of the previous year to 15 April of the nesting year (breeding potential window) and average water depth from 16 April to 31 May of the nesting year (courtship and mating window). Number of pods ranged from 16 in 1998 to 0 in 2011. Each of the four top models included year and one or more of the hydrologic variables as predictors and explained 26–34% (D-squared) of the variation in number of pods. Year was the predictor for which the 95% confidence interval (CI) did not contain 0 and indicated a declining trend (from −3 to −8%; 95% CI). I included all hydrologic variables in the top models, indicating that they contribute some information to explaining the trend; however, contrary to my hypotheses, there was not a clear relationship between any of the hydrologic variables and number of American alligator pods. I based my hypotheses on information synthesized in the American alligator production suitability index model used in Everglades restoration planning, and my results suggest the need for additional refinement of that model.

Birdwatching preferences reveal synergies and tradeoffs among recreation, carbon, and fisheries ecosystem services in Pacific Northwest estuaries, USA

Coastal ecosystems provide multiple ecosystem services that are valued in diverse ways. The Nisqually River Delta (the Delta), an estuary in Puget Sound, Washington, U.S.A., is co-managed by the Nisqually Indian Tribe and the Billy Frank Jr. Nisqually National Wildlife Refuge. In an ecosystem services assessment, we used different service-appropriate methods including citizen science, statistical and geospatial models, and scenario analysis to evaluate three ecosystem services – recreational birdwatching, soil carbon accumulation and fishery production – indicated as priorities for the Refuge, Nisqually Indian Tribe, and surrounding communities. We developed a generalized additive mixed model set based on eBird mobile application birdwatching observations to understand the biological and landscape features that influence birdwatching and to project birdwatching visitation based on scenarios of Delta habitat change. We evaluated ecosystem service synergies and tradeoffs associated with habitat change for three coastal habitat types using scenario outputs from the birdwatching model and published results on Delta soil carbon accumulation and fishery production. The highest-ranked birdwatching models explained 88 % of the deviance and showed that visitation was greatest in winter months when distance to major cities was approximately 20 km. Recreational birdwatching increased with increasing area of forested wetland, emergent wetland, aquatic vegetation bed, open access, and total estuary. With increasing forested and emergent wetland area, recreational birdwatching, out-migrating juvenile Chinook salmon weight and soil carbon accumulation all increased. With increasing aquatic vegetation bed (resulting from sea level rise), recreational birdwatching increased, but salmon weight and soil carbon accumulation decreased. We identified practical ways in which ecosystem services may be incorporated into adaptive management frameworks that support climate adaptation decision making. This study illustrated how use of ecosystem services can help managers make decisions that have greater benefit for wildlife and people, communicate the societal value of decisions and increase local support and participation.

Analysis of bigmouth buffalo Ictiobus cyprinellus spawning phenology in Minnesota reveals 50-year recruitment failure and conservation concern

The bigmouth buffalo Ictiobus cyprinellus (Catostomidae) is a freshwater fish native to North America that is known for its longevity. During the 1970s, the bigmouth buffalo was recorded as declining in Canada, Minnesota, and North Dakota and became a protected species in Canada. In the USA, population declines are exacerbated by wasteful recreational bowfishing, lack of fisheries management, and overall lack of knowledge. However, recent studies have revealed the exceptional lifespan of bigmouth buffalo, their negligible senescence, slow growth, delayed maturity, and episodic recruitment. Yet little is known about the spawning phenology of bigmouth buffalo, nor their age demographics in east central Minnesota. In this 2021–2023 study of bigmouth buffalo from Rice Lake National Wildlife Refuge we found that 99.7% (389 of 390) of the extant population hatched prior to 1972 despite annual spawning in Rice Lake. Moreover, recruitment success declined significantly since water control measures were established (1953). We found males arrive to spawning grounds with females but depart later, that both the midpoint and duration of spawn significantly vary across years, and that more massive females of the same age range invest disproportionately more in ovaries. Extensive post-spawn seining revealed bigmouth buffalo young-of-the-year in low numbers, but by mid-to-late summer they were no longer evident having likely succumbed to predation. Overall, these findings thoroughly reveal one of the oldest populations of vertebrate currently known (median age of 79 years as of 2024) and expose the stark vulnerability of a bigmouth buffalo population for which substantial recruitment has not occurred for more than six decades. Multiple lines of evidence indicate that the long-lived bigmouth buffalo is vulnerable, that a precautionary approach is immediately needed, and that the unlimited and unregulated kill-fishery be closed.

Assessing climate change threats to biodiversity and protected areas of Iran

Our research endeavors to evaluate the precise ramifications of climate change on Iran’s protected regions, utilizing species distribution modeling to anticipate the effects of climate change on 394 bird species, 157 plant species, 72 reptiles, and 20 mammals across two climate change scenarios: SSP245 and SSP585 in 2070. Subsequently, we employed binary species distribution maps to determine the extent of overlap between 125 protected areas, 27 wildlife refuges, and 15 national parks and species distribution, quantifying the proportion of these areas encompassed by their distribution. We found that under the SSP585 scenario, 174 bird species could experience a 319% expansion in suitable habitats, while 220 species could decline by 57.1%. Among plants, 16 species are projected to grow by 40.3%, whereas 141 species may decrease by 68.8%. Reptiles could experience an increase of 279.1% in 24 species, with a 66.6% decrease in 48 species, while mammals may witness a significant increase of 147.3% in 5 species, but a 71.8% decrease in 15 species. Also, under the SSP585 scenario, in national parks, bird coverage declines from 32.2% (current) to 19.9%, plants from 24.2 to 13.2%, reptiles from 18.4 to 6.8%, and mammals from 17.7 to 10%. In wildlife refuges, birds decrease from 9.7 to 5.7%, plants from 10.9 to 4.6%, reptiles from 12.9 to 2.5%, and mammals from 7.4 to 4.3%. In protected areas, birds drop from 29.3 to 20.4%, plants from 27.7 to 12.5%, reptiles from 18.7 to 9.7%, and mammals from 24 to 12.1%. The low overlap of species with national parks, wildlife refuges, and protected areas underscores the importance of re-evaluating and potentially expanding protected areas to ensure they encompass a broader range of habitats, particularly those that are underrepresented, to enhance the conservation of Iran’s biodiversity amidst the challenges posed by climate change.

Do recently translocated black‐footed Albatross (Phoebastria nigripes) chicks respond to artificial social attraction?

AbstractTranslocations of chicks are increasingly being used in seabird restoration projects, along with social attraction of adults using acoustic and visual cues, to establish new colonies or re‐establish extirpated colonies. Many seabird species exhibit high rates of natal philopatry, where most chicks return to the nesting colonies from which they fledged. This makes them ideal candidates for translocation projects since they have a high likelihood of returning to translocation sites if they are relocated prior to imprinting on a natal site. Starting in 2017, Black‐footed Albatross (BFAL) chicks were translocated from populations in the low‐lying Northwestern Hawaiian Islands, where they face habitat loss due to sea level rise, to the higher elevation island of O‘ahu, in an attempt to establish a new colony for this species. Additionally, social attraction was utilized at the site to attract potential nesting adults and provide social stimuli for the translocated chicks. Our study examined the response of translocated BFAL chicks to visual and audio stimuli inside a mammalian predator exclusion fence at James Campbell National Wildlife Refuge on the island of O‘ahu. Decoys constructed in two different poses, representing courtship and resting postures of adult BFAL, were placed in various combinations with playback speakers around the perimeter of artificial shelters. Motion‐activated cameras were used to record and compare the number of visits by chicks to different combinations of visual and acoustic stimuli. We found the number of visits was highest at setups that included a combination of a decoy pair and a playback speaker, suggesting that a combination of visual and audio cues of adult BFAL are most attractive to the chicks. Future studies are needed to evaluate the long‐term impacts of exposure to artificial visual and audio stimuli as chicks on return rates to translocation site and social behavior as adults.

Abundance, production, and migrations of nesting green turtles at Rose Atoll, American Samoa, a regionally important rookery in the Central South Pacific Ocean

Sea turtles are a taxon of conservation concern and are highly migratory, exposing them to a variety of threats (e.g., fisheries bycatch, direct harvest) across their lifetime. Understanding the abundance of nesting females, hatchling production, and migratory movements - three of the most basic biological data needs for this species group - is imperative for population assessment. This study summarizes novel data most relevant to population assessments of the endangered central south Pacific (CSP) green turtle (Chelonia mydas) population, determined from annual rapid assessment surveys (mean survey duration=7.6 days year-1, n=61 survey days over 8 nesting seasons) and satellite telemetry at Rose Atoll, American Samoa, from 2012 to 2019. A minimum of 138 unique females nested in the Rose Atoll National Wildlife Refuge (RANWR) over the study period with 218 total females observed. Satellite tracks of post-nesting females suggest Fiji (n=33/48, 70.2%) is the primary foraging ground for turtles nesting at RANWR, though other areas throughout the south Pacific Ocean are also important. Limited data suggest hatchling production was high (average hatching success=92.3%) and nest temperature data collected from 2017-2019 suggest primary sex ratios were likely balanced during this time. These are positive signs for the resilience of this nesting population, but climate change poses threats to RANWR and other low-lying tropical islands throughout the central south Pacific, as nesting areas are potentially exposed to beach erosion, tidal inundations, and increasing temperatures leading to sex bias and embryonic death.

Monitoring questing winter tick abundance on traditional moose hunting lands

AbstractAn important symbolic and subsistence animal for many Native American Tribes, the moose (Alces alces; mos in Algonquin, Penobscot language) has been under consistent threat in the northeastern United States because of winter tick (Dermacentor albipictus) parasitism over the past several decades, causing declines in moose populations throughout the region. This decline has raised concern for Tribes and agencies that are invested in moose. Given this concern, it is increasingly important to effectively monitor and develop strategies to manage winter ticks to address consistent population declines of moose due to winter ticks. The Penobscot Nation developed a novel strategy to sample questing winter ticks (i.e., ticks that are actively seeking hosts) using a plot‐based sampling protocol that may be suitable for heterogeneous habitats. We deployed this protocol in the northeastern United States in 2022 during the tick questing period (Sep–Dec) on Penobscot Nation sovereign trust lands, the White Mountain National Forest and Umbagog National Wildlife Refuge, and western‐central Massachusetts, USA. We analyzed the data using occupancy and N‐mixture models. Detection probability peaked during mid‐October and tick occupancy and abundance were greatest at sites with intermediate understory vegetation height. The sampling protocol was successful at sampling ticks in Massachusetts, where abundances were expected to be low, indicating that it may be useful for studies planning to monitor winter tick distribution and abundance in areas with sub‐optimal moose habitat and where winter tick abundance is expected to be low. This approach may also benefit managers or researchers intending to monitor many species of hard ticks, and where imperfect detection is expected.

Gyrfalcon Disease Ecology: A Survey Across Western Alaska

ABSTRACT The Gyrfalcon (Falco rusticolus) is a top avian predator, an Arctic specialist, and among the bird species most vulnerable to climate change. This vulnerability is driven by their narrow ecological niche, limited or lack of southward migration, and circumpolar distribution where the most rapid climatic changes are occurring. Climatic and habitat changes may alter Gyrfalcon disease ecology due to changes in vector distributions, host ranges, and pathogen life cycles. Warmer Arctic temperatures and accompanying landscape changes may also alter the Gyrfalcon’s prey base, and dietary habits can influence transmission of pathogens. To better understand disease ecology in Gyrfalcons, we compared pathogen prevalence across varying time periods at three study sites in Alaska—the Seward Peninsula (2014–2022), the Alaska Peninsula (2021–2022), and the Yukon–Kuskokwim Delta (2008–2013). We collected Gyrfalcon whole blood, thin blood films, cloacal swabs, and fecal samples for serology, haemoparasite assays, microbiological cultures, and fecal tests for parasites. An aliquot of whole blood preserved on filter paper or in Longmire solution was kept for molecular diagnosis of haemoparasites. Serology revealed high exposure to Salmonella (77%), low seroprevalence of avian influenza antibodies (1.5%), exposure to falcon adenovirus type 1 in hatch-year Gyrfalcons (1.3%), and the first report of a Leucocytozoon spp. blood parasite in a Gyrfalcon. We found no antibodies indicative of prior exposure to avian paramyxovirus, West Nile virus, or Chlamydia. One nestling and one hatch-year bird sampled (2 of 12) on the Seward Peninsula exhibited oral plaques from capillarids (Eucoelus spp.) in contrast to those trapped in the Izembek National Wildlife Refuge on the Alaska Peninsula (0 of 6).

Can hair snares provide a reliable method for estimating abundance of an exotic ungulate?

Mitigating exotic species invasions requires reliable information on abundance and source-sink dynamics to evaluate effectiveness of control efforts. Despite being present in the southeastern United States for centuries, wild pigs (Sus scrofa) continue to invade new areas, including the Sam D. Hamilton Noxubee National Wildlife Refuge (NNWR) in Mississippi, a forested landscape with an emerging wild pig population. Considering the early stage of invasion, we designed and implemented a non-invasive hair sampling technique to estimate abundance and relatedness of wild pigs within the NNWR. Following 8-week sampling periods in 2021 (n = 160 samples) and 2022 (n = 159 samples), we identified 38 and 26 unique individuals, respectively, although recapture rates were too low to yield precise abundance estimates. We also identified low heterozygosity indicating high relatedness among our population which likely reflected lack of barrier features to gene flow and/or a limited number of external source populations. Finally, we observed positive trends in viable samples collected relative to sampling week, suggesting more optimal sampling period(s) may exist (e.g., autumn). We also acknowledge that use of grain in more accessible areas rather than our remote approach using scent-only attractants may increase hair snare attractiveness and wild pig encounters, while permitting increased sampling frequency. Collectively, these modifications (i.e., altered season, bait type, and access) provide viable pathways to increase precision for abundance estimates. When used concomitantly with ongoing monitoring and control efforts, non-invasive hair sampling will contribute to a more holistic understanding of this exotic species and better inform management actions.

Long-term fertilization increases soil but not plant or microbial N in a Chihuahuan Desert grassland

Abstract. Although the negative consequences of increased nitrogen (N) supply for plant communities and soil chemistry are well known, most studies have focused on mesic grasslands, and the fate of added N in arid and semi-arid ecosystems remains unclear. To study the impacts of long-term increased N deposition on ecosystem N pools, we sampled a 26-year-long fertilization (10 g N m−2 yr−1) experiment in the northern Chihuahuan Desert at the Sevilleta National Wildlife Refuge (SNWR) in New Mexico. To determine the fate of the added N, we measured multiple soil, microbial, and plant N pools in shallow soils at three time points across the 2020 growing season. We found small but significant increases with fertilization in soil-available NO3--N and NH4+-N, yet the soil microbial and plant communities do not appear to be taking advantage of the increased N availability, with no changes in biomass or N content in either community. However, there were increases in total soil N with fertilization, suggesting increases in microbial or plant N earlier in the experiment. Ultimately, the majority of the N added in this multi-decadal experiment was not found in the shallow soil or the microbial or plant community and is likely to have been lost from the ecosystem entirely.

Indigenous peoples and the power(lessness) of public participation: Assessing effects of Indigenous community input in the Alaskan Coastal Plain oil and gas leasing program environmental impact statement

Public participation in the U.S. environmental impact assessment process is legally required under the National Environmental Policy Act, yet the procedural norms of the process often leave members of the public feeling powerless. While public participation has the appearance of a democratic process, it is imbued with unequal power dynamics and federal agencies maintain decision-making authority. Despite sovereignty and treaty rights, Indigenous communities in the U.S. do not participate in environmental decision-making through a collaborative governance structure. Instead, Indigenous communities interested in project impacts primarily voice their concerns through the public comment process. This paper explores Indigenous participants’ impacts on environmental impact decision-making through an illustrative case study structure. The phenomenon is explored in an in-depth analysis of the recent leasing environmental impact statement (EIS) for oil exploration and development in the 1002 Coastal Plain area of the Arctic National Wildlife Refuge in Alaska. This work uses a qualitative content analysis of the Coastal Plain case study to assess how public comments, particularly comments from Indigenous peoples, impact change in the documents that follow public participation processes. From this analysis, this article aims to illustrate a few key issues with how Indigenous input is considered in public participation processes. Findings indicate that public comments may result in minor changes to assessment documents but, overall, public input has little influence on project outcomes.

Using Bayesian multispecies models to evaluate fish and invertebrate detection probability and distribution in the hypersaline Bahia Grande tidal basin

AbstractObjectiveIn 2000, the Laguna Atascosa National Wildlife Refuge acquired the Bahia Grande (Texas) management unit, a space that had lain barren and arid for 70 years. A large cooperative partnership launched a restoration project to replenish the basin and recover its original tidal hydrology. In 2005, the construction of a pilot channel successfully restored water throughout the basin, and plans to eventually widen the channel were developed. Our study aims to evaluate an estuarine habitat restoration by assessing ecological drivers and the impacts on species diversity.MethodsWe evaluated species richness, detection/occupancy rates, and species–habitat relationships, and we estimated the sampling effort required to achieve a given level of relative precision if relative abundance was used instead of occupancy to inform future sampling. Sampling gear included bag seines for juvenile life stages and gill nets for capturing subadult and adult life stages. For analysis, we used a Bayesian negative binomial linear mixed‐effects model to evaluate richness–habitat relationships and a hierarchical Bayesian multispecies model to evaluate individual species–habitat relationships, and we calculated the total number of fish captured and relative standard error by gear and sample year to produce a precise estimate of relative abundance.ResultOverall, 29 species were caught between 2018 and 2021. Salinity emerged as a clear driver in the Bahia Grande, as both species richness and individual‐level responses were negatively associated with high salinity values. We found that catch estimated as relative abundance had much variability, as is typical of most survey programs assuming constant detectability, and the number of net sets or seine hauls required to achieve a given level of relative precision varied considerably depending on the species, season, year, and gear type. The most collected species were found in the upper extremes of their salinity tolerances—potentially a unique adaptation to this hypersaline system.ConclusionBaseline data suggest that for the channel widening to be successful, there must be a noticeable increase in suitable habitat characteristics throughout the basin.

Flexible migration and habitat use strategies of an endangered waterbird during hydrological drought

AbstractWildlife species confront threats from climate and land use change, exacerbating the influence of extreme climatic events on populations and biodiversity. Migratory waterbirds are especially vulnerable to hydrological drought via reduced availability of surface water habitats. We assessed how whooping cranes (Grus americana) modified habitat use and migration strategies during drought to evaluate their resilience to changing conditions and adaptive capacity. We categorized >8000 night‐roost sites used by 146 cranes from 2010 to 2022 and examined relative use during non‐drought, moderate drought, and extreme drought conditions. We found cultivated and uncultivated palustrine and lacustrine wetlands were generally used less during droughts than non‐drought conditions. Conversely, impounded palustrine and lacustrine systems and rivers served more frequently as drought refugia (i.e., used more during drought than non‐drought conditions). Night roosts occurred primarily on private lands (86% overall); public land use decreased with latitude and increased with drought severity, with greatest use (56%) occurring during severe autumn drought in the southern Great Plains. Quantifying use of identified critical habitats in the United States indicated that Cheyenne Bottoms State Waterfowl Management Area and Quivira National Wildlife Refuge were used less during drought, and the Central Platte River and Salt Plains National Wildlife Refuge received similar use during drought compared to non‐drought conditions. Our findings provide insights into compensatory use of habitats, where impounded surface water may function in a complementary fashion with natural wetlands. Collectively, these and other types of wetlands distributed across the migration corridor provided a reliable network of habitat available across the Great Plains. A diversity of wetlands available during variable environmental conditions would be useful in supporting continued recovery of whooping cranes and likely have benefits for a wide array of migratory birds.

Assessment of heavy metal and metalloid concentrations at Horicon National Wildlife Refuge

Assessment of heavy metal and metalloid concentrations at Horicon National Wildlife Refuge

The impacts of United States politics on the Arctic wilderness in Alaska

ABSTRACT The Arctic National Wildlife Refuge (ANWR or the Refuge) has been at the core of the conservation-development debate in the U.S. for over fifty years. The Refuge case epitomizes how policies shape territories governed by overlapping federal, congress, local, and Indigenous regimes. For instance, between 2017 and 2023, the Refuge was opened and closed to hydrocarbon development by two U.S. Presidents. ANWR is among the largest environmental refuges in the U.S. with oil reserve between 4.3 and 11.8 million barrels. Our analysis of U.S. policies about the ANWR shows the contestation between pro-environment and pro-oil development at the federal and state levels. Federal policies of Republican and Democrat administrations align with pro-drilling and pro-environment positions, respectively. Alaskan policymakers are pro-drilling, which puts them at odds with pro-environment legislators from Democratic states. Tensions between Alaska and the Federal government are about control and distribution of the oil revenue. Further, Indigenous peoples are on different sides as well. Traditional Gwich’in oppose development because it threatens their way of life. Iñupiat favor oil development because oil revenue has supported their modernized lifestyle. The fate of the ANWR will shape what happens with protected areas in the U.S. and with species across national boundaries.

Management implications of habitat selection by whooping cranes (Grus americana) on the Texas coast

AbstractEffective habitat management for rare and endangered species requires a thorough understanding of their specific habitat requirements. Although machine learning models have been increasingly used in the analyses of habitat use by wildlife, the primary focus of these models has been on generating spatial predictions. In this study, we used machine learning models in combination with simulated management actions to guide planning and inform managers. We used data from 61 whooping cranes (Grus americana) tagged with GPS telemetry collars between 2009 and 2018 near Aransas National Wildlife Refuge in coastal Texas. We included variables based on topography, land use classification, vegetation height, plant phenology, drought, storm surge events, and both wild and prescribed fires. We then built models at multiple scales: population level, home range level, and roosting and daytime within home range level. We simulated responses to the two primary management actions used to enhance whooping crane habitat on Aransas National Wildlife Refuge: prescribed fire and removal of woody vegetation. At the population and home range scales, land use classification variables had the highest importance values, whereas the combined elevation and bathymetry layer was the most important predictor at both roosting and daytime within home range scales. Our findings revealed that the effects of fire, although generally modest, varied spatially. Areas dominated by estuarine wetlands exhibited higher predicted use within the first months after a fire, whereas those dominated by palustrine wetlands were more likely to be avoided in the immediate postfire years. Our simulation of vegetation removal identified the areas on Aransas National Wildlife Refuge where whooping cranes were predicted to benefit the most if vegetation were removed. These techniques can be used by other researchers wanting to examine and predict the effects of potential management actions on target species habitat.