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USGS2013

Approaches to setting organism-based ballast water discharge standards

As a vector by which foreign species invade coastal and freshwater waterbodies, ballast water discharge from ships is recognized as a major environmental threat. The International Maritime Organization (IMO) drafted an international treaty establishing ballast water discharge standards based on the number of viable organisms per volume of ballast discharge for different organism size classes. Concerns that the IMO standards are not sufficiently protective have initiated several state and national efforts in the United States to develop more stringent standards. We evaluated seven approaches to establishing discharge standards for the >50-μm size class: (1) expert opinion/management consensus, (2) zero detectable living organisms, (3) natural invasion rates, (4) reaction–diffusion models, (5) population viability analysis (PVA) models, (6) per capita invasion probabilities (PCIP), and (7) experimental studies. Because of the difficulty in synthesizing scientific knowledge in an unbiased and transparent fashion, we recommend the use of quantitative models instead of expert opinion. The actual organism concentration associated with a “zero detectable organisms” standard is defined by the statistical rigor of its monitoring program; thus it is not clear whether such a standard is as stringent as other standards. For several reasons, the natural invasion rate, reaction–diffusion, and experimental approaches are not considered suitable for generating discharge standards. PVA models can be used to predict the likelihood of establishment of introduced species but are limited by a lack of population vital rates for species characteristic of ballast water discharges. Until such rates become available, PVA models are better suited to evaluate relative efficiency of proposed standards rather than predicting probabilities of invasion. The PCIP approach, which is based on historical invasion rates at a regional scale, appears to circumvent many of the indicated problems, although it may underestimate invasions by asexual and parthenogenic species. Further research is needed to better define propagule dose–responses, densities at which Allee effects occur, approaches to predicting the likelihood of invasion from multi-species introductions, and generation of formal comparisons of approaches using standardized scenarios.

Ecological Applications↗

USGS2006

Gila monster (Heloderma suspectum)

Like the saguaro cactus (Carnegia gigantea) and the rattlesnake, the Gila monster is emblematic of the desert Southwest. The Gila monster is not only the largest lizard native to the United States, but also one of only two known species of venomous lizard in the Americas. This stout-bodied lizard can grow to 50 cm (20 in) and is covered with black and pink or orange markings and bead-like scales. The Gila monster's range is centered in western and southern Arizona, continuing south to Sonora, Mexico. Despite public fascination with the species, relatively little is known about the ecology and behavior of the Gila monster in the wild. For this reason, managers at Tonto National Monument, Arizona, contacted the U.S. Geological Survey (USGS) to investigate why Gila monsters were being seen in developed areas of the park, particularly crossing the main road. Managers were concerned about possible lizard-human conflicts and the risk of vehicle traffic killing Gila monsters. USGS scientists initiated a research effort in Tonto National Monument beginning in 2004 to provide information needed to make management decisions and improve scientific understanding of the species. Specifically, USGS scientists examined the movement patterns, range requirements, dietary habits, and use of developed areas by Gila monsters within the park. The 2004 research effort also extended a program begun in Tonto National Monument in 1994 to recognize individual Gila monsters based on unique dorsal patterns identified from photographs.

Fact Sheet↗

USGS2000

Interim report on the scientific investigations in the Animas River watershed, Colorado to facilitate remediation decisions by the U.S. Bureau of Land Management and the U.S. Forest Service, March 29, 2000 meeting, Denver, Colo.

INTRODUCTION The joint U.S. Department of the Interior and U.S. Department of Agriculture Abandoned Mine Lands Initiative (AMLI) was developed as a collaborative effort between the Federal land management agencies (FLMA, that is the U.S. Bureau of Land Management and the U.S. Forest Service) and the U.S. Geological Survey (USGS) in 1996. The stated goal of the AML Initiative was to develop a strategy for gathering and communicating the scientific information needed to develop effective and cost-efficient remediation of abandoned mines within the framework of a watershed. Four primary objectives of the AMLI are to: 1. Provide the scientific information needed (in the short-term) by the FLMAs to make decisions related to the design and implementation of cleanup actions, 2. Develop a multi-disciplined, multi-division approach that integrates geologic, hydrologic, geochemical and ecological information into a knowledge base for sound decision making, 3. Transfer technologies developed within the scientific programs of the USGS to the field and demonstrate their suitability to solve real, practical problems, and 4. Establish working relationships among involved members of land management and regulatory agencies within the framework of a watershed approach to the cleanup of abandoned mines. Long-term process-based research, including development of analytical tools, is recognized as being critical to the long-term success in remediating watersheds impacted by historical mining activities (AML 5-year plan, http://amli.usgs.gov/amli). In a meeting of Federal agencies (U.S. Bureau of Land Management [BLM], U.S. Bureau of Reclamation [BOR], U.S. National Park Service [NPS], U.S. Forest Service [USFS], the U.S. Environmental Protection Agency [EPA], the U.S. Fish and Wildlife Service [F&WS]), and State agencies (Colorado Division of Public Health and Environment, Colorado Division of Mines and Geology), several watersheds were examined within the state whose water quality was presumed to be impacted by historical mining activities. The Animas River watershed (fig. 1) was selected by the State and Federal agencies as one of two watersheds in the U.S. to be studied in detail by the USGS in the AML Initiative. Beginning in October 1997, each of the four Divisions of the USGS (Water Resources, Geologic, Biological Resources, and National Mapping) initiated a collaborative integrated science study of the watershed. Funds were provided from USGS base funding to each of the four Divisions in response to the priorities set by Congressional action and within the flexibility provided by the budgetary framework funding individual research programs. The AML Initiative provides for a five-year focused scientific effort in the two watersheds with final synthesis of the scientific results from each to be published in 2001. Publications are released on the AML web site on a regular basis (http://amli.usgs.gov/amli). On March 29, 2000, the USGS hosted a meeting for the BLM and USFS to discuss remediation options that were under consideration for the summer of 2000. The purpose of this report is to provide an overview of the scientific rational provided by the USGS to meet objective one above, and to summarize our preliminary interpretations of our data. Additional information from sites on private lands have been collected by the State of Colorado, EPA, and the ARSG. Unfortunately, these data have not been fully supplied to the USGS so our conclusions are based only upon our data. These interpretations provide science-based constraints on possible remediation options to be considered by the FLMA, the State, and local property owners in the Animas River watershed. The report is presented in outline format to facilitate discussion of remediation options at the March 29, 2000 meeting. Not all historical mining sites within the watershed are on public lands. This should not be construed to be a final report of the USGS

Denver↗

USGS2022

Murky waters: Divergent ways scientists, practitioners, and landowners evaluate beaver mimicry

Beaver mimicry is a fast-growing conservation technique to restore streams and manage water that is gaining popularity within the natural resource management community because of a wide variety of claimed socio-environmental benefits. Despite a growing number of projects, many questions and concerns about beaver mimicry remain. This study draws on qualitative data from 49 interviews with scientists, practitioners, and landowners, to explore the question of how beaver mimicry projects continue to be promoted and implemented, despite the lack of comprehensive scientific studies and unclear regulatory requirements. Specifically, we investigate how these three groups differentially assess the salience, credibility, and legitimacy of evidence for beaver mimicry and analyze how those assessments affect each group’s conclusions about the feasibility, desirability, and scalability of beaver mimicry. By highlighting the interaction between how someone assesses evidence and how they draw conclusions about an emerging natural resource management approach, we draw attention to the roles of experiential evidence and scientific data in debates over beaver mimicry. Our research emphasizes that understanding how different groups perceive salience, credibility, and legitimacy of scientific information is necessary for understanding how they make assessments about conservation and natural resource management strategies.

Ecology and Society↗

USGS2025

The value of reducing uncertainties to support the management of a high‐elevation endemic salamander

Many salamander populations are declining, and methods to determine how best to allocate limited resources to slow or reverse these declines could support land managers in their decision‐making processes. Multiple types of uncertainty may delay management decisions, including when (1) knowledge of a species' ecology is incomplete, (2) climate change effects on environmental covariates are uncertain, and (3) the efficacy of management alternatives is unknown. For management decisions, a value‐of‐information analysis can identify which uncertainties are critical to reduce in order to identify an optimal strategy from a set of possible management actions. If the same management action is optimal across the full range of uncertainties, then resources for research can be redirected toward active management. Using value‐of‐information analyses, we examine the effect of uncertainty on identifying optimal management to maximize the future expected occupancy of Plethodon shenandoah , a Federally Endangered high‐elevation endemic salamander that is threatened by climate change. Out of 11 management actions proposed by National Park Service managers, those that increase environmental moisture are expected to maximize occupancy, and we find that the selection of this action is robust to all the identified uncertainties. We show that, even in systems with multiple sources of large uncertainty, value of information analyses discriminate among investments in species management.

Ecosphere↗

USGS2011

Ecoregional-scale monitoring within conservation areas, in a rapidly changing climate

Long-term monitoring of ecological systems can prove invaluable for resource management and conservation. Such monitoring can: (1) detect instances of long-term trend (either improvement or deterioration) in monitored resources, thus providing an early-warning indication of system change to resource managers; (2) inform management decisions and help assess the effects of management actions, as well as anthropogenic and natural disturbances; and (3) provide the grist for supplemental research on mechanisms of system dynamics and cause-effect relationships (Fancy et al., 2009). Such monitoring additionally provides a snapshot of the status of monitored resources during each sampling cycle, and helps assess whether legal standards and regulations are being met. Until the last 1-2 decades, tracking and understanding changes in condition of natural resources across broad spatial extents have been infrequently attempted. Several factors, however, are facilitating the achievement of such broad-scale investigation and monitoring. These include increasing awareness of the importance of landscape context, greater prevalence of regional and global environmental stressors, and the rise of landscape-scale programs designed to manage and monitor biological systems. Such programs include the US Forest Service's Forest Inventory and Analysis (FIA) Program (Moser et al., 2008), Canada's National Forest Inventory, the 3Q Programme for monitoring agricultural landscapes of Norway (Dramstad et al., 2002), and the emerging (US) Landscape Conservation Cooperatives (USDOI Secretarial Order 3289, 2009; Anonymous, 2011). This Special Section explores the underlying design considerations, as well as many pragmatic aspects associated with program implementation and interpretation of results from broad-scale monitoring systems, particularly within the constraints of high-latitude contexts (e.g., low road density, short field season, dramatic fluctuations in temperature). Although Alaska is the focus of most papers in this Special Section, we posit that many of the issues that characterize the remote, relatively undisturbed ecosystems of high northern latitudes are widespread and thus applicable to natural-resource management and conservation across northern portions of the Holarctic ecozone and indeed anywhere broad-scale monitoring is contemplated.

Biological Conservation↗

USGS2017

Evaluation of genetic population structure of smallmouth bass in the Susquehanna River basin, Pennsylvania

The Smallmouth Bass Micropterus dolomieu was introduced into the Susquehanna River basin, Pennsylvania, nearly 150 years ago. Since introduction, it has become an economically and ecologically important species that supports popular recreational fisheries. It is also one of the most abundant top predators in the system. Currently, there is no information on the level of genetic diversity or genetic structuring that may have occurred since introduction. An understanding of genetic diversity is important for the delineation of management units and investigation of gene flow at various management scales. The goals of this research were to investigate population genetic structure of Smallmouth Bass at sites within the Susquehanna River basin and to assess genetic differentiation relative to Smallmouth Bass at an out-of-basin site (Allegheny River, Pennsylvania) located within the species’ native range. During spring 2015, fin clips ( n = 1,034) were collected from adults at 11 river sites and 13 tributary sites in the Susquehanna River basin and at one site on the Allegheny River. Fin clips were genotyped at 12 polymorphic microsatellite loci. Based on our results, adults sampled throughout the Susquehanna River basin did not represent separate genetic populations. There were only subtle differences in genetic diversity among sites (mean pairwise genetic differentiation index F ST = 0.012), and there was an overall lack of population differentiation ( K = 3 admixed populations). The greatest genetic differentiation was observed between fish collected from the out-of-basin site and those from the Susquehanna River basin sites. Knowledge that separate genetic populations of Smallmouth Bass do not exist in the Susquehanna River basin is valuable information for fisheries management in addition to providing baseline genetic data on an introduced sport fish population.

Pennsylvania↗

USGS2021

Riverscape approaches in practice: Perspectives and applications

Landscape perspectives in riverine ecology have been undertaken increasingly in the last 30 years, leading aquatic ecologists to develop a diverse set of approaches for conceptualizing, mapping and understanding ‘riverscapes’. Spatiotemporally explicit perspectives of rivers and their biota nested within the socio-ecological landscape now provide guiding principles and approaches in inland fisheries and watershed management. During the last two decades, scientific literature on riverscapes has increased rapidly, indicating that the term and associated approaches are serving an important purpose in freshwater science and management. We trace the origins and theoretical foundations of riverscape perspectives and approaches and examine trends in the published literature to assess the state of the science and demonstrate how they are being applied to address recent challenges in the management of riverine ecosystems. We focus on approaches for studying and visualizing rivers and streams with remote sensing, modelling and sampling designs that enable pattern detection as seen from above (e.g. river channel, floodplain, and riparian areas) but also into the water itself (e.g. aquatic organisms and the aqueous environment). Key concepts from landscape ecology that are central to riverscape approaches are heterogeneity, scale (resolution, extent and scope) and connectivity (structural and functional), which underpin spatial and temporal aspects of study design, data collection and analysis. Mapping of physical and biological characteristics of rivers and floodplains with high-resolution, spatially intensive techniques improves understanding of the causes and ecological consequences of spatial patterns at multiple scales. This information is crucial for managing river ecosystems, especially for the successful implementation of conservation, restoration and monitoring programs. Recent advances in remote sensing, field-sampling approaches and geospatial technology are making it increasingly feasible to collect high-resolution data over larger scales in space and time. We highlight challenges and opportunities and discuss future avenues of research with emerging tools that can potentially help to overcome obstacles to collecting, analysing and displaying these data. This synthesis is intended to help researchers and resource managers understand and apply these concepts and approaches to address real-world problems in freshwater management.

Biological Reviews↗

USGS2016

Resource subsidies between stream and terrestrial ecosystems under global change

Streams and adjacent terrestrial ecosystems are characterized by permeable boundaries that are crossed by resource subsidies. Although the importance of these subsidies for riverine ecosystems is increasingly recognized, little is known about how they may be influenced by global environmental change. Drawing from available evidence, in this review we propose a conceptual framework to evaluate the effects of global change on the quality and spatiotemporal dynamics of stream–terrestrial subsidies. We illustrate how changes to hydrological and temperature regimes, atmospheric CO 2 concentration, land use and the distribution of nonindigenous species can influence subsidy fluxes by affecting the biology and ecology of donor and recipient systems and the physical characteristics of stream–riparian boundaries. Climate-driven changes in the physiology and phenology of organisms with complex life cycles will influence their development time, body size and emergence patterns, with consequences for adjacent terrestrial consumers. Also, novel species interactions can modify subsidy dynamics via complex bottom-up and top-down effects. Given the seasonality and pulsed nature of subsidies, alterations of the temporal and spatial synchrony of resource availability to consumers across ecosystems are likely to result in ecological mismatches that can scale up from individual responses, to communities, to ecosystems. Similarly, altered hydrology, temperature, CO 2 concentration and land use will modify the recruitment and quality of riparian vegetation, the timing of leaf abscission and the establishment of invasive riparian species. Along with morphological changes to stream–terrestrial boundaries, these will alter the use and fluxes of allochthonous subsidies associated with stream ecosystems. Future research should aim to understand how subsidy dynamics will be affected by key drivers of global change, including agricultural intensification, increasing water use and biotic homogenization. Our conceptual framework based on the match–mismatch between donor and recipient organisms may facilitate understanding of the multiple effects of global change and aid in the development of future research questions.

Global Change Biology↗

USGS2021

A global ecological classification of coastal segment units to complement marine biodiversity observation network assessments

A new data layer provides Coastal and Marine Ecological Classification Standard (CMECS) labels for global coastal segments at 1 km or shorter resolution. These characteristics are summarized for six US Marine Biodiversity Observation Network (MBON) sites and one MBON Pole to Pole of the Americas site in Argentina. The global coastlines CMECS classifications were produced from a partitioning of a 30 m Landsat-derived shoreline vector that was segmented into 4 million 1 km or shorter segments. Each segment was attributed with values from 10 variables that represent the ecological settings in which the coastline occurs, including properties of the adjacent water, adjacent land, and coastline itself. The 4 million segments were classified into 81,000 coastal segment units (CSUs) as unique combinations of variable classes. We summarize the process to develop the CSUs and derive summary descriptions for the seven MBON case study sites. We discuss the intended application of the new CSU data for research and management in coastal areas.

Oceanography↗

USGS2003

Status of Alabama shad and skipjack herring in Gulf of Mexico drainages

Gulf of Mexico drainages are inhabited by two alosine species, the anadromous Alabama shad Alosa alabamae and the skipjack herring A. chrysochloris. Although their distributions are reasonably well documented, the life history and ecology of both species has been incompletely investigated. Infrequent literature references suggest populations of both species have been adversely affected by river management activities throughout parts of their ranges. This purpose of this paper is to summarize available information concerning past and present distributions, population characteristics, spawning and fecundity, age and growth, and population trends of both species as well as threats to the species. Areas of research are suggested to maintain and possibly recover existing populations. ?? 2003 by the American Fisheries Society.

American Fisheries Society Symposium↗

USGS1993

Managing biological diversity

Biological diversity is the variety of life and accompanying ecological processes (Off. Technol. Assess. 1987, Wilcove and Samson 1987, Keystone 1991). Conservation of biological diversity is a major environmental issue (Wilson 1988, Counc. Environ. Quality 1991). The health and future of the earth's ecological systems (Lubchenco et al. 1991), global climate change (Botkin 1990), and an ever-increasing rate in loss of species, communities, and ecological systems (Myers 1990) are among issues drawing biological diversity to the mainstream of conservation worldwide (Int. Union Conserv. Nat. and Nat. Resour. [IUCN] et al. 1991). The legal mandate for conserving biological diversity is now in place (Carlson 1988, Doremus 1991). More than 19 federal laws govern the use of biological resources in the United States (Rein 1991). The proposed National Biological Diversity Conservation and Environmental Research Act (H.R. 585 and S.58) notes the need for a national biological diversity policy, would create a national center for biological diversity research, and recommends a federal interagency strategy for ecosystem conservation. There are, however, hard choices ahead for the conservation of biological diversity, and biologists are grappling with how to set priorities in research and management (Roberts 1988). We sense disillusion among field biologists and managers relative to how to operationally approach the seemingly overwhelming charge of conserving biological diversity. Biologists also need to respond to critics like Hunt (1991) who suggest a tree farm has more biological diversity than an equal area of old-growth forest. At present, science has played only a minor role in the conservation of biological diversity (Weston 1992) with no unified approach available to evaluate strategies and programs that address the quality and quantity of biological diversity (Murphy 1990, Erwin 1992). Although actions to conserve biological diversity need to be clearly defined by viewing issues across biological, spatial, and temporal scales (Knopf and Smith 1992), natural resource managers find much conflicting information in the literature on strategies and programs for the conservation of biological diversity (Ehrlich 1992). Moreover, recommendations provided in much of the published information available for planning or decisions not only can be debated but may prove counterproductive if implemented. Current operational efforts beg for clearer focus on fundamental concepts central to daily decisions that impact native biological diversity. Recognizing that many biologists would provide different council and at the risk of oversimplification, we offer the following 4 topical issues as fundamental guidance to wise conservation action. These recommendations are based on our collective experiences working within conservation agencies since our original, collaborative essay (Samson and Knopf 1982). They are offered as initial, rather than authoritative, steps to better align research and management decisions with what we perceive as the critical issues in conserving biological diversity at the landscape and ecosystem levels of resolution.

Wildlife Society Bulletin↗

USGS2018

Final report for climate effects on the culture and ecology of sugar maple

Maple syrup is produced from the sap of sugar maple trees collected in the late winter and early spring. Native American tribes have collected and boiled down sap for centuries, and the tapping of maple trees is a cultural touchstone for many people in the northeast and Midwest. Because the tapping season is dependent on weather conditions, there is concern about the sustainability of maple sugaring as climate changes throughout the region. At the same time the demand for this natural sweetener and the production of maple syrup are increasing rapidly. Our research addressed the impact of climate on the quality of maple sap used to make maple syrup. We examined yields coupled with the sugar and biochemical composition of sap collected throughout the geographic range of sugar maple in the northeastern USA and Canada, and related this to historical and projected variation in climate. This is the first study to document potential climate related changes in sap production and sap quality across the full geographic range of sugar maple. Declines, as well as increased variability, in sap flow near the southern range limit and increased sap flow at the northern range limit suggest long term range shifts toward the north, as well as geographic variation in expected syrup production over the next several decades. Survey results highlighted that producers do perceive changes in climate variables and concomitant shifts in sap production. Many producers are willing to shift sap harvesting practices in response to changing climate scenarios, but producers are split in their perceptions about the importance of individual variables and their level of concern about future impacts on the industry. Overall, our results can be applied to design more effective extension programming and adaptation plans to mitigate the risk of climate in maple systems.

Indiana, Kentucky, Massachusetts, New Hampshire, Q↗

USGS2018

Patterns and correlates of giant sequoia foliage dieback during California’s 2012–2016 hotter drought

Hotter droughts – droughts in which unusually high temperatures exacerbate the effects of low precipitation – are expected to increase in frequency and severity in coming decades, challenging scientists and managers to identify which parts of forested landscapes may be most vulnerable. In 2014, in the middle of California’s historically unprecedented 2012–2016 hotter drought, we noticed apparently drought-induced foliage dieback in giant sequoias ( Sequoiadendron giganteum Lindl. [Buchholz]) in Sequoia and Kings Canyon national parks, California. Characteristics of the dieback were consistent with a controlled process of drought-induced senescence: younger (distal) shoots remained green while older (proximal) shoots were preferentially shed. As part of an ongoing interdisciplinary effort to understand and map sequoia vulnerability to hotter droughts, we reviewed historical records for evidence of previous foliage dieback events, surveyed dieback along trail corridors in eight sequoia groves, and analyzed tree-ring data from a high- and a low-foliage-dieback area. In sharp contrast to the greatly elevated mortality of other coniferous species found at low and middle elevations, we estimate that <1% of sequoias died during the drought. Foliage dieback was notably elevated in 2014 – the most severe single drought year in our 122-year record – but much lower in subsequent years. We found no historical records of similar foliage dieback during previous droughts. Dieback in 2014 was highly variable both within and among groves, ranging from virtually no dieback in some areas to nearly 50% in others. Dieback was highest (1) at low elevations, probably due to higher temperatures, reduced snowpack, and earlier snowmelt; (2) in areas of low adult sequoia densities, which likely reflect intrinsically more stressful sites; and (3) on steep slopes, probably reflecting reduced water availability. Average sequoia ring widths were narrower at the high-dieback than the low-dieback tree-ring site, but for reasons that remain unclear the sites did not differ in their proportional ring-width responses to past droughts. Collectively, our results suggest that giant sequoia vulnerability to hotter droughts may be spatially quite variable, and that at least some of that variability can be explained by metrics related to site water balance. Future research will focus on integrating our results with physiological and remote-sensing data, including tracking sequoias as they recover from the drought.

California↗

USGS2021

At-sea feeding ecology of parasitic lampreys

This paper synthesizes information on the at-sea ecology of ten anadromous lampreys, with emphasis on trophic ecology. The at-sea ecology of these lampreys concerns the juvenile stage, in which growth is most rapid. Anadromous lampreys can be categorized into four groups, based on feeding modalities: 1) scavenger (Caspian lamprey, Caspiomyzon wagneri ); 2) parasite-predator (Pacific lamprey, Entosphenus tridentatus ); 3) predators (western river lamprey, Lampetra ayresii ; European river lamprey, L. fluviatilis ; Arctic lamprey, Lethenteron camtschaticum ; pouched lamprey, Geotria australis ; and Argentinian pouched lamprey, G. macrostoma ); and 4) parasites (sea lamprey, Petromyzon marinus ; Chilean lamprey, Mordacia lapicida ; and short-headed lamprey, M. mordax ). This paper discusses direct evidence for lamprey feeding ecology, as observed through lamprey-induced wounds on hosts and prey, and lamprey attachments on hosts and prey; and indirect evidence for feeding ecology, via analyses of fatty acids, stable isotopes, contaminants, and bioenergetics modelling. A part of the information presented on feeding ecology is from landlocked sea lamprey, and in some instances this information can be generalizable to anadromous populations. For most anadromous lampreys, but particularly for Southern Hemisphere taxa, little is known about their feeding ecology at sea. Duration of the trophic marine phase and habitat use are still subjects of debate. Species identified as lamprey hosts can be demersal or pelagic, possibly reflecting marine habitat preferences. To unlock understanding of the marine phase of anadromous lampreys, direct evidence of feeding ecology should be coupled with natural (i.e., biomarkers) and artificial (e.g., biologgers) markers to identify habitat use, movement patterns and dispersal.

Journal of Great Lakes Research↗

USGS2016

Detecting the movement and spawning activity of bigheaded carps with environmental DNA

Bigheaded carps are invasive fishes threatening to invade the Great Lakes basin and establish spawning populations, and have been monitored using environmental DNA (eDNA). Not only does eDNA hold potential for detecting the presence of species, but may also allow for quantitative comparisons like relative abundance of species across time or space. We examined the relationships among bigheaded carp movement, hydrography, spawning and eDNA on the Wabash River, IN, USA. We found positive relationships between eDNA and movement and eDNA and hydrography. We did not find a relationship between eDNA and spawning activity in the form of drifting eggs. Our first finding demonstrates how eDNA may be used to monitor species abundance, whereas our second finding illustrates the need for additional research into eDNA methodologies. Current applications of eDNA are widespread, but the relatively new technology requires further refinement.

Molecular Ecology Resources↗

USGS2022

Increasing the efficiency and power of camera traps for EDRR & ecological monitoring

Invasive species are an ever-growing concern for Florida, especially in important environments like the Greater Everglades Ecosystem. One of the best ways to fight back against invasives is the use of the “Early Detection, Rapid Response” (EDRR) system. The earlier we can detect the presence of a nonnative species, and the faster we respond, the better our chance of stopping its spread. For years, USGS Fort Collins Science Center has been working closely with the National Park Service to use trail cameras to observe the presence of any nonnative species and to monitor research assets in remote locations. Currently, we are working in Everglades National Park to detect invading Black and White Tegu lizards as well as in Big Cypress National Preserve researching the invasive Burmese python and monitoring their nest sites (did you know bobcats eat python eggs!?).

Florida↗

USGS2009

A century of climate and ecosystem change in Western Montana: What do temperature trends portend?

The physical science linking human-induced increases in greenhouse gasses to the warming of the global climate system is well established, but the implications of this warming for ecosystem processes and services at regional scales is still poorly understood. Thus, the objectives of this work were to: (1) describe rates of change in temperature averages and extremes for western Montana, a region containing sensitive resources and ecosystems, (2) investigate associations between Montana temperature change to hemispheric and global temperature change, (3) provide climate analysis tools for land and resource managers responsible for researching and maintaining renewable resources, habitat, and threatened/endangered species and (4) integrate our findings into a more general assessment of climate impacts on ecosystem processes and services over the past century. Over 100 years of daily and monthly temperature data collected in western Montana, USA are analyzed for long-term changes in seasonal averages and daily extremes. In particular, variability and trends in temperature above or below ecologically and socially meaningful thresholds within this region (e.g., -17.8??C (0??F), 0??C (32??F), and 32.2??C (90??F)) are assessed. The daily temperature time series reveal extremely cold days (??? -17.8??C) terminate on average 20 days earlier and decline in number, whereas extremely hot days (???32??C) show a three-fold increase in number and a 24-day increase in seasonal window during which they occur. Results show that regionally important thresholds have been exceeded, the most recent of which include the timing and number of the 0??C freeze/thaw temperatures during spring and fall. Finally, we close with a discussion on the implications for Montana's ecosystems. Special attention is given to critical processes that respond non-linearly as temperatures exceed critical thresholds, and have positive feedbacks that amplify the changes. ?? Springer Science + Business Media B.V. 2009.

Climatic Change↗

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