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At least 73 records · Page 4Linked to original sources
USGS2025

Nocturnal flight call monitoring reveals in-flight behavioral alteration by avian migrants in response to artificial light at night

The world in which birds evolved to migrate has been drastically altered in the Anthropocene by artificial light. Sources of light such as urban centers or bright upward-facing lights attract migrants, altering their behavior, especially during inclement weather, often leading to mortality. Seemingly less extreme sources, such as pole-mounted floodlighting, ubiquitous throughout much of the world, have received comparatively less study, and migrant responses to such sources are poorly understood. We studied migrant behavior in relation to light at White Sands Missile Range (New Mexico, USA) by recording nocturnal flight calls at sites with and without lights during non-inclement weather. We collected 103,424 h of recordings and detected 2,851,863 calls over three fall migration seasons. We assessed how temporal, weather, and lighting variables explain variability in call rates between light and dark sites, and examined how different taxonomic groups behave in relation to light. Contrary to predictions, call rates were higher at dark sites than at light sites, and this difference was strongest early in the migration season. We found illuminated sites with a greater proportion of shielded lights, or with lights of higher dominant wavelengths (warmer color temperatures), had higher call rates (closely resembling dark sites) than other light sites, indicating that these factors may reduce impact to migrants. Our taxonomic analyses revealed consistent differences in call rate between light and dark sites for warblers, but no difference for most sparrows. Our findings indicate that lights alter behavior, but the use of “bird-friendly” lighting strategies may reduce this impact.

New Mexico↗
USGS2022

Quantitative SWOT analysis: A structured and collaborative approach to reintroduction site selection for the endangered Pacific pocket mouse

Species extinction and loss of biodiversity are major crises in the Anthropocene. Translocations of threatened and endangered species, the movement of individuals to augment existing or establish new populations, are increasingly important conservation tools, but have historically had limited success. Selection of a suitable receiver site is essential to translocation success, with poor site suitability cited as one of the most common reasons for relocation failure. We utilized a quantitative SWOT (Strengths, Weaknesses, Opportunities, Threats) analysis to evaluate and prioritize potential receiver sites for the Pacific pocket mouse ( Perognathus longimembris pacificus ), an endangered subspecies of heteromyid rodent endemic to coastal southern California. With only three remaining extant populations, a conservation breeding and reintroduction program is underway with the goal of creating additional wild populations in new or historic locations throughout its indigenous range. Here we describe our use of SWOT analysis and discuss the strengths of this approach as well as improvements that could be made to the evaluation process for other species. Overall, we found that using a structured, transparent, and collaborative process was a valuable tool for prioritizing receiver sites. SWOT analysis is a flexible, repeatable, and proactive approach for identifying receiver sites and the preparations necessary to improve species-specific suitability. This approach has the potential to result in successful relocation compared to less structured site selection processes where poor site suitability is ultimately identified as a major factor in failure to establish wild populations.

California↗
USGS2023

Physicochemical coastal groundwater dynamics between Kauhakō Crater lake and Kalaupapa settlement, Moloka‘i, Hawai‘i

Land-based sources of groundwater pollution can be a critical threat to coral reefs, and a better understanding of “ridge-to-reef” water movement is required to advance management and coral survival in the Anthropocene. In this study a more complete understanding of the geological, atmospheric, and oceanic drivers behind coastal groundwater exchange on the Kalaupapa peninsula, on Moloka‘i, Hawai‘i, is obtained by analyzing high resolution geochemical and geophysical time-series data. In concert with multiyear water level analyses, a tidally and precipitation-driven groundwater connection between Kauhakō Crater lake and submarine groundwater discharge (SGD) fluxes are demonstrated. Results include an average discharge rate of 190 cm d −1 and the detection of water-flow pathways past cesspools that likely contribute to higher nutrient loading near the SGD sites. This underlines the importance of managing anthropogenic nutrients that enter the shallow freshwater lens such as through cesspools and are consequently discharged via SGD onto coral reef habitats.

Hawai'i↗
USGS2024

New uses for ancient middens: Bridging ecological and evolutionary perspectives

Rodent middens provide a fine-scale spatiotemporal record of plant and animal communities over the late Quaternary. In the Americas, middens have offered insight into biotic responses to past environmental changes and historical factors influencing the distribution and diversity of species. However, few studies have used middens to investigate genetic or ecosystem level responses. Integrating midden studies with neoecology and experimental evolution can help address these gaps and test mechanisms underlying eco-evolutionary patterns across biological and spatiotemporal scales. Fully realizing the potential of middens to answer cross-cutting ecological and evolutionary questions and inform conservation goals in the Anthropocene will require a collaborative research community to exploit existing midden archives and mount new campaigns to leverage midden records globally.

Trends in Ecology and Evolution↗
USGS2023

Climate change as a global amplifier of human–wildlife conflict

Climate change and human–wildlife conflict are both pressing challenges for biodiversity conservation and human well-being in the Anthropocene. Climate change is a critical yet underappreciated amplifier of human–wildlife conflict, as it exacerbates resource scarcity, alters human and animal behaviours and distributions, and increases human–wildlife encounters. We synthesize evidence of climate-driven conflicts occurring among ten taxonomic orders, on six continents and in all five oceans. Such conflicts disrupt both subsistence livelihoods and industrial economies and may accelerate the rate at which human–wildlife conflict drives wildlife declines. We introduce a framework describing distinct environmental, ecological and sociopolitical pathways through which climate variability and change percolate via complex social–ecological systems to influence patterns and outcomes of human–wildlife interactions. Identifying these pathways allows for developing mitigation strategies and proactive policies to limit the impacts of human–wildlife conflict on biodiversity conservation and human well-being in a changing climate.

Nature Climate Change↗
USGS2020

The Great Acceleration of fragrances and PAHs archived in an ice core from Elbrus, Caucasus

The Great Acceleration of the anthropogenic impact on the Earth system is marked by the ubiquitous distribution of anthropogenic materials throughout the global environment, including technofossils, radionuclides and the exponential increases of methane and carbon dioxide concentrations. However, personal care products as direct tracers of human domestic habits are often overlooked. Here, we present the first research combining fragrances, as novel personal care products, and Polycyclic Aromatic Hydrocarbons (PAHs) as combustion and industrial markers, across the onset of the Great Acceleration in the Elbrus, Caucasus, ice core. This archive extends from the 1930s to 2005, spanning the profound changes in the relationship between humans and the environment during the 20th century. Concentrations of both fragrances and PAHs rose throughout the considered period, reflecting the development of the Anthropocene. However, within this rising trend, remarkable decreases of the tracers track the major socioeconomic crises that occurred in Eastern Europe during the second half of the 20th century.

Mt. Elbrus, Caucasus↗
USGS2021

Climate and the latitudinal limits of subtropical reef development

Climate plays a central role in coral-reef development, especially in marginal environments. The high-latitude reefs of southeast Florida are currently non-accreting, relict systems with low coral cover. This region also did not support the extensive Late Pleistocene reef development observed in many other locations around the world; however, there is evidence of significant reef building in southeast Florida during the Holocene. Using 146 radiometric ages from reefs extending ~ 120 km along Florida’s southeast coast, we test the hypothesis that the latitudinal extent of Holocene reef development in this region was modulated by climatic variability. We demonstrate that although sea-level changes impacted rates of reef accretion and allowed reefs to backstep inshore as new habitats were flooded, sea level was not the ultimate cause of reef demise. Instead, we conclude that climate was the primary driver of the expansion and contraction of Florida’s reefs during the Holocene. Reefs grew to 26.7° N in southeast Florida during the relatively warm, stable climate at the beginning of the Holocene Thermal Maximum (HTM) ~ 10,000 years ago, but subsequent cooling and increased frequency of winter cold fronts were associated with the equatorward contraction of reef building. By ~ 7800 years ago, actively accreting reefs only extended to 26.1° N. Reefs further contracted to 25.8° N after 5800 years ago, and by 3000 years ago reef development had terminated throughout southern Florida (24.5–26.7° N). Modern warming is unlikely to simply reverse this trend, however, because the climate of the Anthropocene will be fundamentally different from the HTM. By increasing the frequency and intensity of both warm and cold extreme-weather events, contemporary climate change will instead amplify conditions inimical to reef development in marginal reef environments such as southern Florida, making them more likely to continue to deteriorate than to resume accretion in the future.

Florida↗
USGS2019

Widespread global peatland establishment and persistence over the last 130,000 y

Glacial−interglacial variations in CO 2 and methane in polar ice cores have been attributed, in part, to changes in global wetland extent, but the wetland distribution before the Last Glacial Maximum (LGM, 21 ka to 18 ka) remains virtually unknown. We present a study of global peatland extent and carbon (C) stocks through the last glacial cycle (130 ka to present) using a newly compiled database of 1,063 detailed stratigraphic records of peat deposits buried by mineral sediments, as well as a global peatland model. Quantitative agreement between modeling and observations shows extensive peat accumulation before the LGM in northern latitudes (>40°N), particularly during warmer periods including the last interglacial (130 ka to 116 ka, MIS 5e) and the interstadial (57 ka to 29 ka, MIS 3). During cooling periods of glacial advance and permafrost formation, the burial of northern peatlands by glaciers and mineral sediments decreased active peatland extent, thickness, and modeled C stocks by 70 to 90% from warmer times. Tropical peatland extent and C stocks show little temporal variation throughout the study period. While the increased burial of northern peats was correlated with cooling periods, the burial of tropical peat was predominately driven by changes in sea level and regional hydrology. Peat burial by mineral sediments represents a mechanism for long-term terrestrial C storage in the Earth system. These results show that northern peatlands accumulate significant C stocks during warmer times, indicating their potential for C sequestration during the warming Anthropocene.

PNAS↗
USGS2025

Chlorophyll trends are negative for lakes but positive for estuarine–coastal waters

Nutrient (nitrogen and phosphorus) pollution is an environmental problem of global concern because overenrichment of water bodies increases phytoplankton biomass and ecosystem metabolism, depletes oxygen in bottom waters, and increases the frequency and intensity of harmful algal blooms. These responses to nutrient pollution have motivated policies to reduce anthropogenic nutrient inputs. However, these policies have not been universally implemented and their success at reducing phytoplankton biomass is confounded by other components of global change that regulate the conversion of nutrients into biomass. These regulating processes themselves are changing in the Anthropocene. Our study is an assessment of changing phytoplankton biomass over the period 2000–2019, using chlorophyll a trends measured in 191 lakes and 159 estuarine-coastal sites. Our results show that phytoplankton biomass has decreased in most lakes, increased in most coastal sites, and the largest trends have been predominantly negative for lakes and positive for coastal sites. These results provide evidence of opposing directions of phytoplankton biomass change between lakes and coastal sites in this recent period of unprecedented global change. Nutrient pollution is a knotty environmental problem, and our study indicates that it might be a particularly challenging problem for ecosystems situated in densely populated landscapes where freshwater and sea water meet. Success at overcoming this challenge will require deeper scientific understanding of changes in processes that regulate the conversion of nutrients into phytoplankton biomass, substantial investments of time and resources to reduce nutrient inputs, and a flexible strategy designed to anticipate and adapt to a changing world.

PNAS↗
USGS2022

The not-so-dead of winter: Underwater light climate and primary productivity under snow and ice cover in inland lakes

As global surface temperatures continue to rise as a result of anthropogenic climate change, effects in temperate lakes are likely to be more pronounced than in other ecosystems. Decreases in snow and ice cover extent and duration, as well as extended periods of summer stratification have been observed in temperate lake systems throughout the Anthropocene. However, the effects of changing snow and ice cover upon lacustrine communities remain largely uninvestigated. Here, we examined underwater light climate and associated primary productivity patterns under snow-covered and clear lake ice in 6 inland lakes in Minnesota, USA, spanning gradients of water column optical properties (blue, green, brown) associated with trophic status and organic material content. In all lakes, snow cover influenced not only the intensity, but also the spectral signature of light penetrating into the water column. Specifically, the wavelength of maximum penetration was shifted towards longer wavelengths under snow cover in green (eutrophic) lakes, while it was shifted towards shorter wavelengths in blue and brown lakes. Volumetric primary productivity was often higher than anticipated (e.g. ∼1200 mg · m -3 · d -1 ; L. Minnetonka, snow-covered ice). Carbon assimilation rates were lower under snow-covered ice throughout the water column in all lake types, except immediately under cleared ice in eutrophic lakes, where it is likely that phytoplankton were photo-inhibited due to penetration of intense, short-wavelength light. These findings suggest that changing patterns of snow and ice cover under ongoing climate change scenarios can affect patterns of phytoplankton primary productivity in sensitive aquatic ecosystems.

Minnesota↗
USGS2023

Critical stakeholder engagement: The road to actionable science Is paved with scientists’ good intentions

To help stakeholders such as planners, resource managers, policymakers, and decision makers address environmental challenges in the Anthropocene, scientists are increasingly creating actionable science—science that is useful, usable, and used. Critical physical geography encourages the engagement of stakeholders in the creation of scientific knowledge to conduct actionable science and produce outputs that are directly relevant to stakeholder plans, decisions, or actions. Many scientists, however, lack formal training in how to partner with stakeholders using effective and ethical practices. In this article, we use the core principles for ethical research of respect for persons, beneficence, and justice from the Belmont Report (1979) as a suggested framework to examine the perspectives of stakeholders engaged in climate adaptation science projects. We argue that this framework aligns with the principles of critical physical geography and provides guidance for scientists to make their research more actionable while placing necessary emphasis on ethical considerations. We also challenge scientists to consider the broader ethical implications of engaging with these partners.

Annals of the American Association of Geographers↗
USGS2018

Where have all the turtles gone, and why does it matter?

Of the 356 species of turtles worldwide, approximately 61% are threatened or already extinct. Turtles are among the most threatened of the major groups of vertebrates, in general, more so than birds, mammals, fishes or even the much besieged amphibians. Reasons for the dire situation of turtles worldwide include the familiar list of impacts to other species including habitat destruction, unsustainable overexploitation for pets and food, and climate change (many turtles have environmental sex determination). Two notable characteristics of pre-Anthropocene turtles were their massive population sizes and correspondingly high biomasses, the latter among the highest values (over 855 kilograms per hectare) ever reported for animals. As a result of their numerical dominance, turtles have played important roles as significant bioturbators of soils, infaunal miners of sea floors, dispersers and germination enhancers of seeds, nutrient cyclers, and consumers. The collapse of turtle populations on a global scale has greatly diminished their ecological roles.

BioScience↗
USGS2022

Using transcriptomics to predict and visualize disease status in bighorn sheep (Ovis canadensis)

Increasing risk of pathogen spillover coupled with overall declines in wildlife population abundance in the Anthropocene make infectious disease a relevant concern for species conservation worldwide. While emerging molecular tools could improve our diagnostic capabilities and give insight into mechanisms underlying wildlife disease risk, they have rarely been applied in practice. Here, employing a previously reported gene transcription panel of common immune markers to track physiological changes, we present a detailed analysis over the course of both acute and chronic infection in one wildlife species where disease plays a critical role in conservation, bighorn sheep ( Ovis canadensis ). Differential gene transcription patterns distinguished between infection statuses over the course of acute infection and differential correlation (DC) analyses identified clear changes in gene co-transcription patterns over the early stages of infection, with transcription of four genes—TGFb, AHR, IL1b and MX1—continuing to increase even as transcription of other immune-associated genes waned. In a separate analysis, we considered the capacity of the same gene transcription panel to aid in differentiating between chronically infected animals and animals in other disease states outside of acute disease events (an immediate priority for wildlife management in this system). We found that this transcription panel was capable of accurately identifying chronically infected animals in the test dataset, though additional data will be required to determine how far this ability extends. Taken together, our results showcase the successful proof of concept and breadth of potential utilities that gene transcription might provide to wildlife disease management, from direct insight into mechanisms associated with differential disease response to improved diagnostic capacity in the field.

Conservation Physiology↗
USGS2020

Pheromone pollution from invasive sea lamprey misguides a native confamilial

Animals living in the Anthropocene search for mates facing a barrage of pollutants. Few studies consider pheromones from invasive species as pollution, but their central role in the lives of many animals indicates cross-reaction among historically allopatric relatives has potentially damaging impacts. We hypothesized the sex pheromone of sea lamprey (Petromyzon marinus), an invasive fish in the Laurentian Great Lakes, misguides mate search in native chestnut lamprey (Ichthyomyzon castaneus). In a field test, 100 % of female I. castaneus chose male odourants from P. marinus over conspecifics. Chemical analysis of water in which males were held confirmed both species signal with 3-keto petromyzonol sulfate but revealed higher release rates in P. marinus. Our results indicate sex pheromones from invasive species can be an influential type of pollution and underscore the conservation implications of studies on pheromone evolution.

Current Zoology↗
USGS2021

The ecology and evolution of synchronized reproduction in long-lived plants

Populations of many long-lived plants exhibit spatially synchronized seed production that varies extensively over time, so that seed production in some years is much higher than on average, while in others, it is much lower or absent. This phenomenon termed masting or mast seeding has important consequences for plant reproductive success, ecosystem dynamics and plant–human interactions. Inspired by recent advances in the field, this special issue presents a series of articles that advance the current understanding of the ecology and evolution of masting. To provide a broad overview, we reflect on the state-of-the-art of masting research in terms of underlying proximate mechanisms, ontogeny, adaptations, phylogeny and applications to conservation. While the mechanistic drivers and fitness consequences of masting have received most attention, the evolutionary history, ontogenetic trajectory and applications to plant–human interactions are poorly understood. With increased availability of long-term datasets across broader geographical and taxonomic scales, as well as advances in molecular approaches, we expect that many mysteries of masting will be solved soon. The increased understanding of this global phenomenon will provide the foundation for predictive modelling of seed crops, which will improve our ability to manage forests and agricultural fruit and nut crops in the Anthropocene.

Philosophical Transactions of the Royal Society B:↗
USGS2022

The socioecology of fear: A critical geographical consideration of human-wolf-livestock conflict

Animal fear can be an important driver of ecological community structure: predators affect prey not only through predation, but by inducing changes in behavior and distribution—a phenomenon evocatively called the “ecology of fear.” The return of wolves to the western United States is a notable instance of such dynamics, yet plays out in a complex socio-ecological system where efforts to mitigate impacts on livestock rely on manipulating wolves’ fear of people. Examining Washington state’s efforts to affect wolf behavior to reduce livestock predation, we argue that this approach to coexistence with wolves is predicated on relations of fear: people, livestock, and wolves can arguably share landscapes with minimal conflict, as long as wolves are adequately afraid. We introduce the “socioecology of fear” as an interdisciplinary framework for examining the interwoven social and ecological processes of human-wildlife conflict management. Beyond frequently-voiced ideas about wolves’ “innate” fear, we examine how fear is (re)produced through human-wolf interactions and deeply shaped by human social processes. We contribute to the Critical Physical Geography project by integrating critical social analysis with ecological theory, conducted through collaborative interdisciplinary dialogue. Such integrative practice is essential for understanding the complex challenges of managing wildlife in the Anthropocene.

Washington↗
USGS2019

Integrating anthropogenic factors into regional-scale species distribution models — A novel application in the imperiled sagebrush biome

Species distribution models (SDM) that rely on regional-scale environmental variables will play a key role in forecasting species occurrence in the face of climate change. However, in the Anthropocene, a number of local-scale anthropogenic variables, including wildfire history, land-use change, invasive species, and ecological restoration practices can override regional-scale variables to drive patterns of species distribution. Incorporating these human-induced factors into SDMs remains a major research challenge, in part because spatial variability in these factors occurs at fine scales, rendering prediction over regional extents problematic. Here, we used big sagebrush (Artemisia tridentata Nutt.) as a model species to explore whether including human-induced factors improves the fit of the SDM. We applied a Bayesian hurdle spatial approach using 21,753 data points of field-sampled vegetation obtained from the LANDFIRE program to model sagebrush occurrence and cover by incorporating fire history metrics and restoration treatments from 1980 to 2015 throughout the Great Basin of North America.

Global Change Biology↗
USGS2023

Ecosystem resilience to invasion and drought: Insights after 24 years in a rare never-grazed grassland

Understanding the resilience of ecosystems globally is hampered by the complex and interacting drivers of change characteristic of the Anthropocene. This is true for drylands of the western US, where widespread alteration of disturbance regimes and spread of invasive non-native species occurred with westward expansion during the 1800s, including the introduction of domestic livestock and spread of Bromus tectorum , an invasive non-native annual grass. In addition, this region has experienced a multi-decadal drought not seen for at least 1200 years with potentially large and interacting impacts on native plant communities. Here, we present 24 years of twice-annual plant cover monitoring (1997–2021) from a semiarid grassland never grazed by domestic livestock but subject to a patchy invasion of B. tectorum beginning in ~1994, compare our findings to surveys done in 1967, and examine potential climate drivers of plant community changes. We found a significant warming trend in the study area, with more than 75% of study year temperatures being warmer than average (1966–2021). We observed a native perennial grass community with high resilience to climate forcings with cover values like those in 1967. In invaded patches, B. tectorum cover was greatest in the early years of this study (1997–2001; ~20%–40%) but was subsequently constrained by climate and subtle variation in soils, with limited evidence of long-term impacts to native vegetation, contradicting earlier studies. Our ability to predict year-to-year variation in functional group and species cover with climate metrics varied, with a 12-month integrated index and fall and winter patterns appearing most important. However, declines to near zero live cover in recent years in response to regional drought intensification leave questions regarding the resiliency of intact grasslands to ongoing aridification and whether the vegetation observations reported here may be a leading indicator of impending change in this protected ecosystem.

Utah↗