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USGS2013

Consideration of reference points for the management of renewable resources under an adaptive management paradigm

The success of natural resource management depends on monitoring, assessment and enforcement. In support of these efforts, reference points (RPs) are often viewed as critical values of management-relevant indicators. This paper considers RPs from the standpoint of objective-driven decision making in dynamic resource systems, guided by principles of structured decision making (SDM) and adaptive resource management (AM). During the development of natural resource policy, RPs have been variously treated as either ‘targets’ or ‘triggers’. Under a SDM/AM paradigm, target RPs correspond approximately to value-based objectives, which may in turn be either of fundamental interest to stakeholders or intermediaries to other central objectives. By contrast, trigger RPs correspond to decision rules that are presumed to lead to desirable outcomes (such as the programme targets). Casting RPs as triggers or targets within a SDM framework is helpful towards clarifying why (or whether) a particular metric is appropriate. Further, the benefits of a SDM/AM process include elucidation of underlying untested assumptions that may reveal alternative metrics for use as RPs. Likewise, a structured decision-analytic framework may also reveal that failure to achieve management goals is not because the metrics are wrong, but because the decision-making process in which they are embedded is insufficiently robust to uncertainty, is not efficiently directed at producing a resource objective, or is incapable of adaptation to new knowledge.

Environmental Conservation↗

USGS1987

Analysis of trends in water-quality data for water conservation area 3A, the Everglades, Florida

Rainfall and water-quality data bases from the South Florida Water Management District were used to evaluate water quality trends at 10 locations near or in Water Conservation Area 3A in The Everglades. The Seasonal Kendall test was applied to specific conductance, orthophosphate-phosphorus, nitrate-nitrogen, total Kjeldahl nitrogen, and total nitrogen regression residuals for the period 1978-82. Residuals of orthophosphate and nitrate quadratic models, based on antecedent 7-day rainfall at inflow gate S-11B, were the only two constituent-structure pairs that showed apparent significant (p < 0.05) increases in constituent concentrations. Elimination of regression models with distinct residual patterns and data outlines resulted in 17 statistically significant station water quality combinations for trend analysis. No water quality trends were observed. The 1979 Memorandum of Agreement outlining the water quality monitoring program between the Everglades National Park and the U.S. Army Corps of Engineers stressed collection four times a year at three stations, and extensive coverage of water quality properties. Trend analysis and other rigorous statistical evaluation programs are better suited to data monitoring programs that include more frequent sampling and that are organized in a water quality data management system. Pronounced areal differences in water quality suggest that a water quality monitoring system for Shark River Slough in Everglades National Park include collection locations near the source of inflow to Water Conservation Area 3A. (Author 's abstract)

Florida↗

USGS2018

New insights into the phylogenetics and population structure of the prairie falcon (Falco mexicanus)

Background Management requires a robust understanding of between- and within-species genetic variability, however such data are still lacking in many species. For example, although multiple population genetics studies of the peregrine falcon ( Falco peregrinus ) have been conducted, no similar studies have been done of the closely-related prairie falcon ( F. mexicanus ) and it is unclear how much genetic variation and population structure exists across the species’ range. Furthermore, the phylogenetic relationship of F. mexicanus relative to other falcon species is contested. We utilized a genomics approach (i.e., genome sequencing and assembly followed by single nucleotide polymorphism genotyping) to rapidly address these gaps in knowledge. Results We sequenced the genome of a single female prairie falcon and generated a 1.17 Gb (gigabases) draft genome assembly. We generated maximum likelihood phylogenetic trees using complete mitochondrial genomes as well as nuclear protein-coding genes. This process provided evidence that F. mexicanus is an outgroup to the clade that includes the peregrine falcon and members of the subgenus Hierofalco. We annotated > 16,000 genes and almost 600,000 high-quality single nucleotide polymorphisms (SNPs) in the nuclear genome, providing the raw material for a SNP assay design featuring > 140 gene-associated markers and a molecular-sexing marker. We subsequently genotyped ~ 100 individuals from California (including the San Francisco East Bay Area, Pinnacles National Park and the Mojave Desert) and Idaho (Snake River Birds of Prey National Conservation Area). We tested for population structure and found evidence that individuals sampled in California and Idaho represent a single panmictic population. Conclusions Our study illustrates how genomic resources can rapidly shed light on genetic variability in understudied species and resolve phylogenetic relationships. Furthermore, we found evidence of a single, randomly mating population of prairie falcons across our sampling locations. Prairie falcons are highly mobile and relatively rare long-distance dispersal events may promote gene flow throughout the range. As such, California’s prairie falcons might be managed as a single population, indicating that management actions undertaken to benefit the species at the local level have the potential to influence the species as a whole.

BMC Genomics↗

USGS2014

Hydrostratigraphic interpretation of test-hole and borehole geophysical data, Kimball, Cheyenne, and Deuel Counties, Nebraska, 2011-12

Recently (2004) adopted legislation in Nebraska requires a sustainable balance between long-term supplies and uses of surface-water and groundwater and requires Natural Resources Districts to understand the effect of groundwater use on surface-water systems when developing a groundwater-management plan. The South Platte Natural Resources District (SPNRD) is located in the southern Nebraska Panhandle and overlies the nationally important High Plains aquifer. Declines in water levels have been documented, and more stringent regulations have been enacted to ensure the supply of ground-water will be sufficient to meet the needs of future generations. Because an improved understanding of the hydrogeologic characteristics of this aquifer system is needed to ensure sustainability of groundwater withdrawals, the U.S. Geological Survey, in cooperation with the SPNRD, Conservation and Survey Division of the University of Nebraska-Lincoln, and the Nebraska Environmental Trust, began a hydrogeologic study of the SPNRD to describe the lithology and thickness of the High Plains aquifer. This report documents these characteristics at 29 new test holes, 28 of which were drilled to the base of the High Plains aquifer. Herein the High Plains aquifer is considered to include all hydrologically connected units of Tertiary and Quaternary age. The depth to the base of aquifer was interpreted to range from 37 to 610 feet in 28 of the 29 test holes. At some locations, particularly northern Kimball County, the base-of-aquifer surface was difficult to interpret from drill cutting samples and borehole geophysical logs. The depth to the base of aquifer determined for test holes drilled for this report was compared with the base-of-aquifer surface interpreted by previous researchers. In general, there were greater differences between the base-of-aquifer elevation reported herein and those in previous studies for areas north of Lodgepole Creek compared to areas south of Lodgepole Creek. The largest difference was at test hole 5-SP-11, where an Ogallala-filled paleovalley prevously had been interpreted based on relatively sparse test-hole data west of 5-SP-11. The base of aquifer near test hole 5-SP-11 reported herein is approximately 230 ft higher in elevation than previously interpreted. Among other test holes that are likely to have been drilled in Ogallala-filled paleovalleys, the greatest difference in the interpreted base of aquifer was for test hole 7-CC-11, northeast of Potter, Nebraska, where the base of aquifer is 180 feet deeper than previously interpreted. Interpretation of test-hole and borehole geophysical data for 29 additional test holes will improve resource managers’ understanding of the hydrogeologic characteristics, including aquifer thickness. Aquifer thickness, which is related to total water in storage, is not well quantified in the north and south tablelands. The additional hydrostratigraphic interpretations provided in this report will improve the hydrogeologic framework used in current (2014) and future groundwater models, which are the basis for many water-management decisions.

Nebraska↗

USGS2015

Monitoring landscape-level distribution and migration Phenology of Raptors using a volunteer camera-trap network

Conservation of animal migratory movements is among the most important issues in wildlife management. To address this need for landscape-scale monitoring of raptor populations, we developed a novel, baited photographic observation network termed the “Appalachian Eagle Monitoring Program” (AEMP). During winter months of 2008–2012, we partnered with professional and citizen scientists in 11 states in the United States to collect approximately 2.5 million images. To our knowledge, this represents the largest such camera-trap effort to date. Analyses of data collected in 2011 and 2012 revealed complex, often species-specific, spatial and temporal patterns in winter raptor movement behavior as well as spatial and temporal resource partitioning between raptor species. Although programmatic advances in data analysis and involvement are needed, the continued growth of the program has the potential to provide a long-term, cost-effective, range-wide monitoring tool for avian and terrestrial scavengers during the winter season. Perhaps most importantly, by relying heavily on citizen scientists, AEMP has the potential to improve long-term interest and support for raptor conservation and serve as a model for raptor conservation programs in other portions of the world.

Wildlife Society Bulletin↗

USGS2023

Mammalian resistance to megafire in western U.S. woodland savannas

Increasingly frequent megafires are dramatically altering landscapes and critical habitats around the world. Across the western United States, megafires have become an almost annual occurrence, but the implication of these fires for the conservation of native wildlife remains relatively unknown. Woodland savannas are among the world's most biodiverse ecosystems and provide important food and structural resources to a variety of wildlife, but they are threatened by megafires. Despite this, the great majority of fire impact studies have only been conducted in coniferous forests. Understanding the resistance and resilience of wildlife assemblages following these extreme perturbations can help inform future management interventions that limit biodiversity loss due to megafire. We assessed the resistance of a woodland savanna mammal community to the short-term impacts of megafire using camera trap data collected before, during, and after the fire. Specifically, we utilized a 5-year camera trap data set (2016–2020) from the Hopland Research and Extension Center to examine the impacts of the 2018 Mendocino Complex Fire, California's largest recorded wildfire at the time, on the distributions of eight observed mammal species. We used a multispecies occupancy model to quantify the effects of megafire on species' space use, to assess the impact on species size and diet groups, and to create robust estimates of fire's impacts on species diversity across space and time. Megafire had a negative effect on the detection of certain mammal species, but overall, most species showed high resistance to the disturbance and returned to detection and site use levels comparable to unburned sites by the end of the study period. Following megafire, species richness was higher in burned areas that retained higher canopy cover relative to unburned and burned sites with low canopy cover. Fire management that prevents large-scale canopy loss is critical to providing refugia for vulnerable species immediately following fire in oak woodlands, and likely other mixed-forest landscapes.

California↗

USGS2026

Behavioral shifts mask the success of legislation and outreach for endangered species recovery

A fundamental challenge in conservation is assessing the efficacy of recovery actions to optimize endangered species management. Considerable recent attention has focused on effective measures to counter the endangerment of avian scavengers, which have declined worldwide, primarily due to poisoning. One iconic example is efforts to recover the critically endangered California condor ( Gymnogyps californianus ), whose leading cause of death is poisoning from ingesting lead-based ammunition in carcasses. Despite enormous resources expended in California, USA, including implementation of public outreach campaigns and two legislative bans on lead ammunition, lead-related mortality of condors has increased. Here we show that two types of behavioral shifts explain the observed increases in condor lead exposure: wilder foraging and ranging by condors and increased shooting of wild pigs ( Sus scrofa ) by humans. After accounting for these trends, we show that both lead ammunition bans and public outreach efforts have significantly reduced condor blood lead levels in California, lowering mortality. Our analyses uncover a dynamic in which changing ecological conditions mask the true efficacy of legislation and outreach. Given rapid global change, such dynamics are likely operating in many settings, underscoring the importance of comprehensive evaluations of recovery actions, which can be obscured by shifting behaviors and threats.

Baja California, California↗

USGS2019

Back to the future: Rebuilding the Everglades

Society values landscapes that are engrained in cultural tradition and have a rich connection with human history. As such, there has been a concerted effort to look at the pristine past and develop plans to move the past into the future. However, bringing the past back is constrained by hysteretic changes, irrevocable damages, and anthropogenic trends that do not reflect past conditions. The scale of the Everglades and its importance to water supply and flood control is such that a full recovery, to past, pre-drainage conditions, is not possible. What is possible? The answer is the federally authorized Comprehensive Everglades Restoration Plan (CERP) and the first, most significant implementation of the $12 Billion CERP is the $2 Billion Central Everglades Planning Project (CEPP). CEPP is our “flux-capacitor” in the DeLorean sports car that generates the ability to go back and forth in time, in the movie series “Back to the Future.” The primary hydrological modeling outputs of CEPP came from a version of the Regional Simulation Model (RSM), developed by the South Florida Water Management District. The RSM is the DeLorean vehicle, designed to carry the bags of ecological restoration. Unfortunately, the capacity of this vehicle (i.e., CEPP) is limited, but is it large enough? Will CEPP make a difference? The 20-year RSM simulations (1965 – 1985) without restoration showed nine dry periods when there was no water in the sloughs of Everglades National Park (ENP). When the model was run with CEPP conditions, all of these extreme dry conditions were eliminated. The impact of this was most apparent for fish, especially the size classes that wading birds eat. With our DeLorean (i.e. the RSM) we saw a 60-90% increase in fish density. As one might expect, the birds in our alternative future responded to the fish. The increased volume, flow, and connectivity in the CEPP simulations significantly improved the foraging response of all wading bird species, especially in Water Conservation Area 3 (WCA-3) and ENP. Foraging conditions for an average CEPP year improved by 25-100%. Further downstream, the CEPP simulations showed increased delivery of low nutrient fresh water to the Coastal Everglades and Florida Bay that displaced the relatively P-rich marine water, increased water transparency, and thus decreased algal blooms. However, in a future with accelerating sea levels and estuarine lakes with legacy phosphorus (P), how much more fresh water will be needed to maintain submerged aquatic vegetated habitats? The quest for Everglades Restoration will reach a resource management milestone with the implementation of CEPP. CEPP successfully used a broad suite of hydrological, ecological and societal models to build an acceptable and feasible adaptive management vision of the future. It has been a long and difficult journey, but what we have learned in the process will guide future travelers back in time.

Florida↗

USGS2024

A strategic and science-based framework for management of invasive annual grasses in the sagebrush biome

In the last 20 years, the North American sagebrush biome has lost over 500,000 ha of intact and largely intact sagebrush plant communities on an annual basis. Much of this loss has been associated with expansion and infilling of invasive annual grasses (IAGs). These species are highly competitive against native perennial grasses in disturbed environments, and create fuel conditions that increase both the likelihood of fire ignition and the ease of wildfire spread across large landscapes. Given the current rate of IAG expansion in both burned and unburned rangelands, ameliorating the IAG threat will involve a range-wide paradigm shift from opportunistic and reactive management, to a framework that spatially prioritizes maintenance of largely intact, uninvaded areas and improvement of invaded habitats in strategic locations. We created a framework accompanied by biome-wide priority maps using geospatial overlays that target areas to MAINTAIN large, uninvaded areas as natural resource anchors through activities to prevent IAGs and IMPROVE areas to reduce invasions with the highest potential for management efforts to succeed in restoring large, intact landscapes. We then offer three case studies to illustrate the use of these concepts and map products at multiple scales. Our map products operate at the biome scale using regional data sources but additional data sources may be needed to inform local conservation planning. However, the basic strategic management principles of a) maintaining the intact and uninvaded areas that we can least afford to lose to IAGs and b) improving areas where we have a higher likelihood of restoration success, is timely, relevant, and scalable from the biome to local levels.

Rangeland Ecology & Management↗

USGS2001

GRA prospectus: optimizing design and management of protected areas

Protected areas comprise one major type of global conservation effort that has been in the form of parks, easements, or conservation concessions. Though protected areas are increasing in number and size throughout tropical ecosystems, there is no systematic method for optimally targeting specific local areas for protection, designing the protected area, and monitoring it, or for guiding follow-up actions to manage it or its surroundings over the long run. Without such a system, conservation projects often cost more than necessary and/or risk protecting ecosystems and biodiversity less efficiently than desired. Correcting these failures requires tools and strategies for improving the placement, design, and long-term management of protected areas. The objective of this project is to develop a set of spatially based analytical tools to improve the selection, design, and management of protected areas. In this project, several conservation concessions will be compared using an economic optimization technique. The forest land use portfolio model is an integrated assessment that measures investment in different land uses in a forest. The case studies of individual tropical ecosystems are developed as forest (land) use and preservation portfolios in a geographic information system (GIS). Conservation concessions involve a private organization purchasing development and resource access rights in a certain area and retiring them. Forests are put into conservation, and those people who would otherwise have benefited from extracting resources or selling the right to do so are compensated. Concessions are legal agreements wherein the exact amount and nature of the compensation result from a negotiated agreement between an agent of the conservation community and the local community. Funds are placed in a trust fund, and annual payments are made to local communities and regional/national governments. The payments are made pending third-party verification that the forest expanse and quality have been maintained.

Open-File Report↗

USGS2005

Effectiveness of a confinement strategy for reducing campsite impacts in Shenandoah National Park

The expansion and proliferation of backcountry campsites is a persistent problem in many parks and protected areas. Shenandoah National Park (SNP) has one of the highest backcountry overnight use densities in the USA national parks system. SNP managers implemented a multi-option backcountry camping policy in 2000 that included camping containment with established campsites. These actions were intended to reduce the number of campsites and the area of camping disturbance at each site. This paper describes a longitudinal adaptive management assessment of the new campsite policies, applying quantitative measures of campsite conditions to evaluate the efficacy of management interventions. Physical campsite measurements combined with qualitative visitor interviews indicated SNP had successfully reduced the number of campsites and aggregate measures of camping-related disturbance in the Park, while minimizing the use of regulations, site facilities and staff resources. Implications for managers of other protected areas are that an established site camping policy can minimize camping disturbance, including the number and size of campsites, provided managers can sustain rehabilitation efforts to close and restore unneeded campsites. Experiential attributes, such as the potential for solitude, can also be manipulated through control over the selection of established campsites. Integrating resource and social science methods also provided a more holistic perspective on management policy assessments. Adaptive management research provided a timely evaluation of management success while facilitating effective modifications in response to unforeseen challenges. Conclusions regarding the effectiveness of a visitor impact containment strategy involving an established site camping option are offered.

Virginia↗

USGS2015

Age, growth rates, and paleoclimate studies of deep sea corals

Deep-water corals are some of the slowest growing, longest-lived skeletal accreting marine organisms. These habitat-forming species support diverse faunal assemblages that include commercially and ecologically important organisms. Therefore, effective management and conservation strategies for deep-sea corals can be informed by precise and accurate age, growth rate, and lifespan characteristics for proper assessment of vulnerability and recovery from perturbations. This is especially true for the small number of commercially valuable, and potentially endangered, species that are part of the black and precious coral fisheries (Tsounis et al. 2010). In addition to evaluating time scales of recovery from disturbance or exploitation, accurate age and growth estimates are essential for understanding the life history and ecology of these habitat-forming corals. Given that longevity is a key factor for population maintenance and fishery sustainability, partly due to limited and complex genetic flow among coral populations separated by great distances, accurate age structure for these deep-sea coral communities is essential for proper, long-term resource management.

Report↗

USGS2020

Potential impacts of future urbanization and sea level rise on Florida’s natural resources

As urban development continues to encroach into natural systems, these ecosystems experience increasing degradation to their form and function. Losses in biodiversity and ecosystem function are further compounded by changing climatic conditions. The State of Florida is known for its biodiversity but has experienced declines in species populations and habitats because of urbanization and sea level rise. These declines are particularly challenging in an economy that benefits from a multibillion-dollar income from natural resources tourism. In this study, we assessed the potential future impacts of urbanization and sea level rise on a suite of conservation targets that have been set for the State. We developed six scenarios of all combinations of intermediate and high sea level rise paired with two types of urbanization (sprawling and compact) in both 2040 and 2070 to examine the potential future threats to conservation targets in High Pine and Scrub, Coastal Uplands, and Freshwater Aquatics ecosystems. Our results show projected decreases in extent and area of these priority ecosystems into the future. Florida's current trend in urbanization practices are projected to have a greater impact on conservation targets than if sprawl reduction practices are implemented. Coastal Uplands are projected to experience the greatest loss in area, at up to 47%. Conservation-focused urban planning and climate adaptation strategies can help protect Florida's natural resources with benefits to Florida's tourism economy as well as critical ecosystem functions and services such as coastal flood protection and storm surge risk reduction.

Florida↗

USGS2018

Drain tiles and groundwater resources: Understanding the relations

Executive Summary Drainage for agricultural production over the past 150 years has been an integral component of human-driven change to Minnesota’s rural landscapes. Benefits of drainage Historically, poorly drained soils across much of the State would often remain saturated or flooded after spring snowmelt, preventing timely farm operations such as tilling and planting crops (Arneman, 1963). Installation of agricultural drainage, both surface ditches and subsurface drainage, accelerated transport of water off farm fields and imparted producers higher crop yields (Beauchamp, 1987; Stoner and others, 1993). Agricultural drainage offered many other benefits such as preventing crop drown out, aerating the soil profile for improved plant growth, limiting surface runoff and soil erosion, and allowing farmers better access to croplands (Fausey and others, 1987). Without agricultural drainage on much of Minnesota’s croplands, it would have been difficult to realize high enough crop yields to remain economically viable. Environmental concerns While drainage of Minnesota croplands provided the benefits mentioned above, several environmental concerns result. These include wetland loss, degradation of downstream water quality, and reduced [potential for] recharge. Early agricultural drainage efforts (pre-20th century) led to the disappearance of much of Minnesota’s natural wetlands. Increased focus on preventing or mitigating wetland loss over the last 50 years has helped curtail further losses, even as agricultural drainage proceeds. Prior to establishment of Minnesota statehood, wetlands accounted for more than 10 million acres in Minnesota, including prairie wetlands, peatlands, and forest wetlands that comprised approximately 19 percent of the total land area (Palmer, 1915; King, 1980). In 2018, only half of Minnesota’s pre-settlement wetlands remain, mostly in parts of the State that have not experienced widespread drainage, such as northern Minnesota. Water-quality monitoring has shown that agricultural drainage, in particular the practice of subsurface drainage, provides a direct flow path for nutrient (nitrogen and soluble phosphorus) losses to surface water resources. The negative consequences of agricultural drainage on surface water quality are well documented (for example, Dinnes and others, 2002; Kladivko and others, 2004; Richards and others, 2008; Rozemeijer and others, 2010; Schottler and others, 2013). Agricultural basins with a high percentage of agricultural drainage have been implicated as part of the cause of the Gulf of Mexico hypoxia zone due to excessive nitrogen export (Goolsby and Battaglin, 2001; Randall and Mulla, 2001). The connection of hydrological effects of agricultural subsurface drainage on groundwater recharge and aquifers, on the other hand, has not been well-established. Agricultural subsurface drainage intercepts infiltrating water below croplands and directly discharges the water to nearby surface waters. However, the size of the water balance shift from drained water that would have evapotranspired or run off the land to drained water that would recharge underlying aquifers has been poorly characterized (Schuh, 2008). Drain Tiles and Groundwater Given the poor accounting of subsurface drainage effects on groundwater resources, the Minnesota Ground Water Association (MGWA) deemed it imperative that we document these effects so that groundwater resources in agricultural regions with substantial drainage can be effectively managed. This white paper documents the relations of drain tiles and groundwater resources and discusses the historical significance of agricultural drainage practices, the recognized positive benefits and potential negative consequences of agricultural drainage practices, and the gaps in understanding of the connections between agricultural drainage and groundwater resources. The major messages emerged from the findings of this white paper are: Complex history. Minnesota has a long history of agricultural drainage, spanning over 150 years. Agricultural drainage, and the eventual widespread usage of subsurface drainage, can be separated into at least four distinct periods of time: (a) early drainage to get water off the land, pre-20th century; (b) the boom and bust era (1900-1945); (c) postwar resurgence of subsurface drainage and early conservation efforts (1945-1960); and, (d) emergence of the environmental movement (1960 to present). The State’s regulatory framework that both allowed for drainage and controlled its usage during these periods is complicated and has been governed by a patchwork of both State and Federal statutes. Drainage Provinces. This white paper advances the concept of tile drainage provinces to aid in the discussion of regional differences in subsurface drainage and its overall effect on groundwater resources. Built upon the concept of groundwater provinces (Minnesota Department of Natural Resources, 2001), three distinct tile drainage provinces were conceptualized: (1) the Southeastern Province; (2) the SouthCentral Province; and, (3) the Western Province. The distinct geology and the soils that developed in these regions have implications for each region’s subsurface drainage density and the potential implications for groundwater. Knowledge gaps. Several critical knowledge gaps are identified in this paper, creating opportunities for further research to improve our understanding for better managed water resources: Extent of drainage is unknown. Direct estimates of the extent of subsurface drainage do not exist in Minnesota. However, several indirect methods have been utilized to estimate subsurface drainage, from the field-scale to countylevel through the use of geographic information system (GIS) analysis and aerial photography. Based on a 2012 U.S. Geological Survey estimate of subsurface drainage extent (Nakagaki and Wieczorek, 2016), about 21% of the land area in Minnesota has some density of subsurface drainage. Effect of drainage on underlying aquifers is unknown. A basic understanding of unconfined and confined aquifers and their recharge is necessary to connect any hydrological effects from agricultural drainage to groundwater. The basic goal of subsurface drainage to efficiently drain saturated soils clearly alters the water balance in croplands. However, its overall effect on groundwater resources has been poorly characterized, and is in large part determined by the geology below drained areas and the arrangement of underlying aquifers. Water balance shifts. An improved understanding of historical water balance shifts from pre- to post-drainage periods is necessary to understand long-term implications on net groundwater recharge. Also, more direct field-scale studies and indirect modeling studies are needed to characterize water budgets for fields with subsurface drainage.

Minnesota↗

USGS2020

Development of microsatellite markers for three at risk tiger beetles Cicindela dorsalis dorsalis, C. d. media, and C. puritana

Objective Tiger beetles inhabiting sandy beaches and cliffs along the east coast of the United States are facing increasing habitat loss due to erosion, urbanization, and sea level rise. The northeastern beach tiger beetle Cicindela dorsalis dorsalis and Puritan tiger beetle Cicindela puritana are both listed as threatened under the Endangered Species Act of 1973, while the white beach tiger beetle Cicindela dorsalis media is not listed but has been declining. Extirpation of these beetles, in some cases from entire states, has isolated many populations reducing gene flow and elevating the risk for the loss of genetic variation. To facilitate investigations of population genetic structure, we developed suites of microsatellite loci for conservation genetic studies. Results Shotgun genomic sequencing of all species identified thousands of candidate microsatellite loci, among which 17 loci were optimized and verified to cross-amplify within C. d. media and C. d. dorsalis , and eight separate loci were optimized for C. puritana . Most loci conformed to Hardy–Weinberg equilibrium, showed no evidence of linkage disequilibrium or null alleles, and revealed population genetic characteristics informative for natural resource managers among the populations tested.

BMC Research Notes↗

USGS2007

Land Cover Applications, Landscape Dynamics, and Global Change

The Land Cover Applications, Landscape Dynamics, and Global Change project at U.S. Geological Survey (USGS) Center for Earth Resources Observation and Science (EROS) seeks to integrate remote sensing and simulation models to better understand and seek solutions to national and global issues. Modeling processes related to population impacts, natural resource management, climate change, invasive species, land use changes, energy development, and climate mitigation all pose significant scientific opportunities. The project activities use remotely sensed data to support spatial monitoring, provide sensitivity analyses across landscapes and large regions, and make the data and results available on the Internet with data access and distribution, decision support systems, and on-line modeling. Applications support sustainable natural resource use, carbon cycle science, biodiversity conservation, climate change mitigation, and robust simulation modeling approaches that evaluate ecosystem and landscape dynamics.

Fact Sheet↗

USGS2020

Population and habitat analyses for greater sage-grouse (Centrocercus urophasianus) in the bi-state distinct population segment—2018 update

Executive Summary The Bi-State Distinct Population Segment (Bi-State DPS) of greater sage-grouse ( Centrocercus urophasianus , hereinafter “sage-grouse”) represents a genetically distinct and geographically isolated population that straddles the border between Nevada and California. The primary threat to these sage-grouse populations is the expansion of single-leaf pinyon ( Pinus monophylla ) and Utah juniper ( Juniperus osteosperma ) into sagebrush ecosystems, which fragments and reduces population connectivity and survival. Other important threats include low water availability during brood-rearing, particularly during drought, and increased predation by common ravens ( Corvus corax ), a generalist predator often associated with anthropogenic resource subsidies. Although the Bi-State DPS occurs at high elevations relative to sage-grouse range-wide, changes in historical wildfire cycles and the conversion of native shrubs to invasive annual grasslands still threaten these populations. The Bi-State DPS has undergone multiple federal status assessments and associated litigation. For example, in October of 2013, the Bi-State DPS was proposed for listing as threatened under the Endangered Species Act of 1973 by the U.S. Fish and Wildlife Service (USFWS), then withdrawn in April 2015. The withdrawal decision was challenged, and in May 2018, a Federal district court ordered the withdrawal decision to be vacated, and USFWS was required to re-open the October 2013 listing evaluation. In response, the U.S. Geological Survey (USGS), with State and Federal collaborators, embarked on a multipronged analysis to provide current and best available science regarding population status of sage-grouse within the Bi-State DPS. Using data from a long-term monitoring program, we carried out four analytical study objectives, and here, we provide preliminary results of these analyses. First, we used integrated population modeling (IPM) to predict annual population abundance and annual finite rate of population change for the Bi-State DPS, as a whole, and for each subpopulation between 1995 and 2018. Because sage-grouse exhibit population cycles (periodic increases and decreases in abundance across approximately 6- to 10-year wavelengths), we estimated trends across three nested temporal scales that represent one (11 years), two (18 years), and three (24 years) complete population cycles. These estimates of relatively long-term averaged population change account for temporal (that is, interannual) variation. Our model predicted population abundance for the Bi-State DPS during 2018 at 3,305 individuals (2,247–4,683), with the majority occupying Bodie Hills and Long Valley. The model also predicted cyclic dynamics in abundance through time with evidence of 24-year population growth and slight trends of decline over the past 18 years. Specifically, across the Bi-State DPS as a whole, we estimated annual average at 0.99, 0.99, and 1.02 over the one, two, and three population cycles, which equated to a 10.5 percent, 16.6 percent decrease, and 60.0 percent increase in abundance over the 11-, 18-, and 24-year cycles. Estimated abundance in 2018 had not reached numbers lower than those predicted during 1995. However, we found spatial variation in population trends across the three cycles. Bodie Hills subpopulation comprised the greatest (1,521) and exhibited average annual greater than 1.0 across all periods resulting in average annual increases of 7 percent. This relatively large subpopulation has grown 5 times larger than what was predicted in 1995 while experiencing cyclical dynamics within that period. Conversely, other smaller subpopulations within the Bi-State DPS exhibited average annual equal to or less than 1.0 resulting in estimated 10-year risks of extirpation ranging from 2.0 to 76.1 percent. In general, evidence of decline among smaller subpopulations was greatest for the most recent period (2008–18) compared to a period that encompassed three full population cycles (24-year). This difference coincides with an intense period of drought that began in 2012. For comparative purposes as part of this first objective, we conducted a similar analysis for populations of sage-grouse within Nevada and California but outside the Bi-State DPS. We developed a region-wide and distance-weighted IPM using lek count from Nevada Department of Wildlife (NDOW) and California Department of Fish and Wildlife (CDFW) databases and with telemetry data collected by USGS across 12 sage-grouse subpopulations. Our models predicted similar patterns in population cycling outside the Bi-State DPS but with much stronger evidence of long-term declines across 24 years. Specifically, median averaged across each year of the 11-, 18-, and 24-year periods resulted in average annual values of 0.94, 0.97, and 0.99, respectively. These values equate to 41.0 percent, 38.5 percent, and 21.3 percent declines over the corresponding periods. Second, we used lek count data in a state-space modeling framework to compare trends in population abundance across different spatial scales (that is, leks versus Bi-State DPS). This hierarchical framework allowed us to disentangle declines associated with climate conditions as opposed to other local level factors that might signal the need for management intervention. Specifically, we identified 7 leks that were both declining and recently decoupled from larger spatial scale trends, typically governed by climatic conditions (referred to as soft or hard signals). The goal of this analysis was to provide an early warning system that might have implications for conservation actions at local scales. Third, we developed phenological (spring, summer–fall, and winter) and reproductive life stage (nesting, early brood-rearing, and late-brood rearing) based resource selection functions using various environmental covariates. We report rankings of variable importance for each season and life stage, developed maps of habitat selection indices (HSI), binned categories representing low, moderate, and high classes of quality (where any category greater than or equal to low indicated selected habitat) for each phenological season and life stage, and produced composite maps by selected phenological and reproductive stage to estimate annual habitat. Fourth, we used for each lek within the Bi-State DPS to carry out a spatial analysis that quantified substantial changes in the distribution of occupied habitat across long- (24-year) and short- (11-year) term periods. Owing to differences among available datasets, the long-term analysis primarily reflected spatial shifts among subpopulations comprising the majority of the Bi-State DPS (that is, Bodie Hills and Long Valley) while the short-term analysis also quantified changes among subpopulations along the periphery. Over long and short-term periods, the overall distribution of occupied habitat (as measured by 99 percent utilization distributions intersecting any quantified habitat) was reduced by 20,573 ha and 55,492 ha, respectively. Occupied core areas (as measured by 50 percent utilization distributions intersecting any quantified habitat) over long-term periods were solely located in Bodie Hills and Long Valley. Although nearly all subpopulations experienced contractions in occupied overall and core distribution, Bodie Hills experienced spatial expansion that occurred with concomitant spatial contraction at Long Valley over both periods. Subpopulations at the northern (Pine Nuts), central (Sagehen) and southern (White-Mountains) extents of the Bi-State DPS also experienced spatial contraction over the short-term period. These findings, coupled with those of population trends, indicate long-term patterns in redistribution of sage-grouse from Long Valley and peripheral subpopulations to Bodie Hills. That is, sage-grouse subpopulations at the periphery are declining while the largest population at the core is increasing, which could have meaningful impacts on overall metapopulation persistence. We provide evidence for loss of occupied habitat (reduced distribution) given local extirpation of subpopulations. Fifth, we calculated percentages of selected phenological, life stage, and annual habitat that each subpopulation contributed to the Bi-State DPS. We then intersected these maps with a composite estimate of occupied habitat from the fourth objective and calculated percentages of selected habitat likely occupied by sage-grouse that each subpopulation contributed to the Bi-State DPS. These values provide evidence for loss of occupied habitat and subsequent reductions in spatial distribution given reductions in abundance and, in some cases, extirpation of leks within subpopulations. Lastly, we carried out an initial in-depth analysis of selection for irrigated pastures and wet meadows during the brood-rearing stage for the Long Valley subpopulation. We chose this subpopulation because it represents a population core, representing 26.5 percent of total sage-grouse within the Bi-State DPS, and has exhibited long-term declines in abundance and distribution. This subpopulation is highly sensitive to precipitation and other factors that influence water availability. Models predicted higher use of the interior portions of irrigated pastures and wet meadows during late brood-rearing period, which represented a potentially risky use of habitat that was exacerbated during periods of low moisture (for example, drought, reduced water delivery, or both). Sage-grouse typically used edges of riparian areas and pastures, largely because the interior of these mesic areas consisted of considerably less overhead concealment cover (for example, shrubs) that likely resulted in a higher risk of mortality. We found that a lack of water delivery to pastures in the form of overwinter precipitation or diversion ditches increased the movements of sage-grouse to the interior of pastures. Although further investigation of water delivery impacts on chick survival are warrented, our initial findings regarding resource selection may explain recent declines in population growth at Long Valley.

California, Nevada↗

USGS2022

Annual summer submersed macrophyte standing stocks estimated from long-term monitoring data in the Upper Mississippi River

System-scale restoration efforts within the Upper Mississippi River National Wildlife and Fish Refuge have included annual monitoring of submersed aquatic vegetation (SAV) since 1998 in four representative reaches spanning ∼ 440 river kilometers. We developed predictive models relating monitoring data (site-scale SAV abundance indices) to diver-harvested SAV biomass, used the models to back-estimate annual standing stock biomass between 1998 and 2018, and compared biomass estimates with previous abundance measures. We modeled two morphologically distinct groups of SAV with differing sampling efficiencies and estimated each separately: the first category included only wild celery Vallisneria americana, which has long, unbranched leaves and dominates lotic environments, while the second category included 17 branched morphology species (e.g., hornwort Ceratophyllum demersum and Canadian water weed Elodea canadensis ) and dominates lentic environments. Wild celery accounted for approximately half of total estimated total biomass in the four reaches, combined branched species accounted for half, and invasive species (Eurasian watermilfoil Myriophyllum spicatum and curly-leaf pondweed Potamogeton crispus ), a fraction of the branched species, accounted for < 1.5%. Site-scale SAV estimates ranged from 0 to 535 g·m −2 (dry mass). We observed increases in biomass in most areas between 1998 and 2009 and substantial increases (e.g., from < 10 g·m −2 to ∼ 125 g·m −2 ) in wild celery in extensive impounded areas between 2002 and 2007. Analyses also indicate a transitional period in 2007–2010 during which changes in biomass trajectories were evident in all reaches and included the start of a 9-y, ∼ 70% decrease in wild celery biomass in the southernmost impounded area. Biomass estimates provided new insights and illustrated scales of change that were not previously apparent using traditional metrics. The ability to estimate biomass from Long Term Resource Monitoring data improves conservation efforts through better understanding of changes in habitat and food resources for biota, improved goal setting for restoration projects and improved quantification of SAV-mediated structural effects such as anchoring of sediments and feedbacks with water quality.

Illinois, Iowa, Minnesota, Wisconsin↗