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At least 1,099 records · Page 61Linked to original sources

USGS2026

Low streamflows in Massachusetts: Variability over space and time and relations with climatic and basin variables

Streamflows in Massachusetts have set record lows in recent years despite generally wetter conditions than during the drought of the 1960s, and the reasons for this are not known. To analyse potential drivers of low streamflows in Massachusetts, six low-flow metrics were computed at 107 streamgages. These metrics represent low-flow magnitude, magnitude normalized to median flows, and duration. Multiple linear regressions were used to analyse the variability of low flows over space and time. Potential explanatory variables were computed using climatic, land use, water use, and basin data. For all low-flow metrics, the ratio of precipitation to potential evapotranspiration (P/PET) in July–August explained the most variability, with decreasing P/PET largely explained by lower precipitation. Water/wetland area was a significant explanatory variable in all the normalized-magnitude and duration models, with greater area associated with lower normalized magnitudes and with shorter durations of low flows. Human influence (characterized by development, population, water use, and artificial water storage) had mixed effects. Trends from 1983 to 2022 in summer P/PET and human influence have been strongest in the eastern part of the state where the strongest decreases in flows are observed. Low flows in Massachusetts seem to be driven by a combination of low summer precipitation and human effects, though the specific mechanisms of human influence on flow likely vary between basins.

Massachusetts↗

USGS2026

Ecovoltaic solar energy development creates novel microclimate, temperature, and soil moisture patterns under solar panels in a warm desert

Background: As solar energy development expands in desert regions, new installation practices and solar technologies seek to balance ecosystem conservation and energy generation (ecovoltaics). The Gemini Solar Project, a large ecovoltaic facility located in the northeastern Mojave Desert, employed low impact installation methods to reduce disturbance of the desert ecosystem within arrays of bifacial panels mounted on solar tracking systems. We evaluated microclimate and environmental conditions across five locations: four within-facility microsites (underneath solar panels, east and west panel driplines, and interspaces between panel rows) and one in the undisturbed desert outside the facility. Results: Under panel microsites experienced lower solar radiation and evaporative demand than panel driplines, and driplines experienced lower solar radiation and evaporative demand than interspaces and undisturbed desert outside the facility. Air temperature was similar among microsites, whereas soil surface temperature was highest in interspaces and lower in under-panel and dripline microsites due to diurnal panel shading. Soil temperature was higher under panels compared to interspaces from March to September and lower in other months, and higher during daytime and lower at nighttime periods. Panel tracking and the more frequent occurrence of afternoon precipitation promoted higher soil moisture in west driplines. Water redistribution was also influenced by soil hydraulic conductivity—deep soils experienced greater west dripline soil moisture, whereas shallow soils experienced surface water pooling and greater soil moisture in the west dripline and under solar panels. Conclusions: Gemini’s ecovoltaic design promotes microclimate heterogeneity, moderating some environmental conditions while intensifying others, and often differing from fixed panel facilities with higher disturbance. This research provides critical information to balance renewable energy expansion and ecological function in warm deserts.

Nevada↗

USGS2026

Making many out of one: Synthetic geologic deformation model distributions for use in USGS NSHM25‐PRVI Puerto Rico-U.S. Virgin Island update

A key use‐case of geologic slip rates is within deformation models used in probabilistic seismic hazard analyses. Field‐derived geologic slip rates have formed the cornerstone of deformation models in such applications for decades. Recent advancements in seismic hazard analyses have expanded the use of faults for which geologic slip rates are not well constrained using categorical slip rate estimates. Because of these advancements, application of a geologic deformation model for use in 2025 U.S. Geological Survey National Seismic Hazard Model Puerto Rico‐U.S. Virgin Islands (NSHM25‐PRVI) proved challenging due to: (1) a lack of field‐based geologic slip rates, and (2) a lack of epistemic uncertainty distributions within a broad range of estimated slip rates. Preliminary versions of the NSHM25‐PRVI model sampled these slip rate bins in a coincident manner along preferred and extreme value branches, which yielded untenable correlations in mean hazard results. To minimize the influence of correlated uncertainties amid these challenges, we develop a synthetic epistemic uncertainty distribution for deformation rate on each crustal fault. Each fault has a weighting schema across four possible distribution shapes: uniform, normal, triangular favoring local minima, and triangular favoring local maxima. The synthetic distributions are then sampled several times for each logic tree branch. The results provide a more realistic distribution of rates across the study region as compared with using correlated extrema sampling. This exploration of our method in a small region like PRVI can pave the way for larger‐scale, more complicated applications (e.g., western United States).

Puerto Rico, US Virgin Islands↗

USGS2026

Earthquake ground-motion model adjustments for the San Francisco Bay area

We develop adjustments to ergodic ground‐motion models (GMMs) to improve their performance in the San Francisco Bay Area (SFBA). GMMs are widely used in hazard assessments to estimate characteristics of ground shaking based on known properties of the source, path, and site. Such models are often developed using datasets containing records from various regions, resulting in models that represent median ground‐motion behavior, which may not adequately represent ground motions within subregions. This is true for the SFBA, where ground motions attenuate more rapidly with distance than in many other parts of California that dominate GMM databases. To support improved seismic hazard estimates in the SFBA, we calculate regional constants and anelastic attenuation coefficient adjustments relative to two commonly used ergodic GMMs: BSSA14 ( Boore et al. , 2014 ) and ASK14 ( Abrahamson et al. , 2014 ). These adjustments are obtained for a suite of ground‐motion intensity measures (peak ground acceleration, peak ground velocity, and 5%‐damped pseudospectral acceleration at oscillator periods ranging from 0.075 to 10 s) using mixed‐effects regression. Use of the regionally adjusted models reduces the overall bias by up to 0.5 natural log units for BSSA14 and up to 0.6 natural log units for ASK14. We demonstrate one application of our attenuation adjustments and their implications in an earthquake early warning case study of the 2014 M 6.0 South Napa earthquake. The predicted extent of shaking using the adjusted models better matches observed shaking at large source‐to‐site distances, especially for lower shaking intensities, thus potentially reducing overalerting. We encourage the use of our model adjustments when ergodic models are considered for seismic hazard studies in the SFBA.

California↗

USGS2026

Only very strong shaking can break a tree

A handful of credible accounts, both recent and historical, describe trees being broken during earthquakes. Apart from landslides and tsunamis, such accounts are uncommon, suggesting that trees break only when ground acceleration is extreme or when trees are especially vulnerable to breakage. Here, I consider the question: what ground acceleration is required to break a living tree? I present simplified first‐principles calculations, considering the properties of common trees, focusing on tall, thin trees that can be approximated as uniform vertical cantilevers. The results suggest that, possibly excepting tall trees with heavy canopies, standing trees can only be broken by shaking approaching or exceeding 1 g , as anticipated by the rarity of documented accounts of snapped trees. I briefly consider several well‐documented instances of tree damage during strong earthquakes, drawing inferences about local ground motions.

The Seismic Record↗

USGS2026

Post-hatch ecology, diet, and first migration of juvenile Alaskan Bar-tailed Godwits

Life stages between hatching and adult recruitment are poorly described for most migratory shorebird species and represent a critical knowledge gap in understanding long-term population dynamics. We conducted a pilot study on the Seward Peninsula, Alaska, to assess the feasibility of following juvenile Bar-tailed Godwits Limosa lapponica baueri from their breeding grounds to their non-breeding grounds in New Zealand and Australia. Radio-tracked broods were highly mobile and moved hundreds to thousands of meters per day. They used low-elevation wetlands with dense shrub cover when younger, and more open, tundra-dominated ridgetops when older. Using DNA metabarcoding analysis of fecal samples, we found that chick diet consisted largely of flying insects (e.g. Tenthredinidae and Ichneumonidae) and small gastropods and appeared to increase in diversity with chick age. We followed one brood to near-fledging (ca. 26 days old) and deployed 5-g satellite transmitters on three chicks. One of these subsequently moved to the Yukon-Kuskokwim Delta, from where it flew 11 days and an estimated 13,391 km to Tasmania, which is the longest non-stop flight recorded for landbirds. These results provide the first information on the ecology of pre- and post-fledging young Bar-tailed Godwits in Alaska, and will inform future efforts to study this important life stage.

Alaska↗

USGS2026

Geologic map of the Emmons Lake volcanic center, Alaska

Introduction The Emmons Lake volcanic center is a spatially clustered group of stratovolcanoes and calderas in the southwestern part of the Alaska Peninsula, Alaska. The volcanic center is characterized by several ice- and snow-clad stratovolcanoes located within and along the margins of a nested-caldera complex that includes Emmons Lake. A shieldlike ancestral edifice (ancestral Mount Emmons) is truncated by the caldera complex and forms a broad volcanic platform around the center. The main stratovolcanoes of the Emmons Lake volcanic center are Pavlof Sister, Pavlof Volcano, Little Pavlof, Double Crater, Mount Hague, and Mount Emmons. Several small unnamed cinder cones and vents also are located within Emmons Lake volcanic center and on the east flank of Pavlof Volcano. Many of these cones and vents have been the source of the young lava flows that mantle the floor of the caldera. Pavlof Volcano, in the northeastern part of the Emmons Lake volcanic center, is one of the most historically (that is, the past about 300 years) active volcanoes in Alaska, and eruptions from Pavlof Volcano pose the greatest hazards to the region. Volcanic rocks of the Emmons Lake volcanic center overlie continental and marine sedimentary rocks of chiefly Late Jurassic to early Tertiary age. The oldest rocks in the area are those of the Naknek Formation, consisting of volcaniclastic sandstone, siltstone, and conglomerate of Late Jurassic age. The southern part of the area includes rocks of the Belkofski Formation, a thick sequence of volcaniclastic sandstone, siltstone, and conglomerate of middle Tertiary age. Lava flows, volcanic breccia, and fluvial volcaniclastic rocks of late Miocene age, which unconformably overlie the Belkofski Formation south of the Emmons Lake volcanic center, are primarily exposed on the islands just south of the Alaska Peninsula. The Emmons Lake volcanic center was affected multiple times by glaciation associated with the glacier expansion that characterized the Quaternary. Glaciation has played a key role in shaping the present-day landscape, and much of the eruptive history of the Emmons Lake volcanic center has involved interactions with glacier ice. Thus, a brief review of the Quaternary glacial history of the area is provided to establish the physical context for Emmons Lake volcanic center eruptive activity.

Alaska↗

USGS2026

Thickness and other characteristics of overbank sediment deposited during an extreme flood in May 1978 along the Powder River, Montana

An extreme flood on the Powder River in southeastern Montana in May 1978 inundated its valley and deposited sediment on the floodplains and terraces at multiple heights. The recurrence interval for this flood was less than 1 percent in the reach between Moorhead and Broadus, Montana. Peak discharges at the U.S. Geological Survey streamgages at Moorhead and Broadus were 779 and 711 cubic meters per second (m 3 /s), respectively, the difference reflecting the water and sediment stored on the valley surfaces. Bankfull discharge depended on the height of the bank at the start of the valley transect and varied from 243 to 713 m 3 /s. Sediment-thickness and particle-size data were collected and analyzed in the autumn of 1978 by U.S. Geological Survey scientists at about 900 sites along 20 valley transects between Moorhead and Broadus, Mont. These transects were approximately orthogonal to the floodflow across the floodplain from near the edge of the channel to the high-water mark. Estimated maximum flood depths along these transects ranged from 0.9 to 4.2 meters. Contrary to theory and controlled laboratory experiments, the distribution of sediment thickness and particle sizes along valley transects did not decrease systematically with distance from the main channel but were affected by the distribution of vegetation. Additionally, some water and sediment—primarily muds and silts—were conveyed by subsidiary channels (often connected to the main channel downriver from the valley transect) during the early stages of the flood before water overtopped the banks at the start of the valley transect. The vegetation created natural sediment traps in the recirculation and wake zones in the lee of trees and shrubs. Sediment that accumulated in these traps formed dunes and thus an undulating surface with many local maximums and minimums in sediment thicknesses. Sediment in the traps are referred to as lee dunes, which recorded flow conditions and a predominance of coarsening-upward sequence of particle sizes (mud to silt to sands) starting at the preflood surface. These sequences were associated with the rising limb of the hydrograph, and later as the flood began to recede, the lee dunes recorded a fining-upward sequence associated with the falling limb of the hydrograph.

Montana↗

USGS2026

Multiscale resource selection for a reintroduced elk population

Patterns of resource selection are driven by the decision-making processes of animals occurring at multiple scales from where to establish a home range (i.e., second order selection) to which resource patches to use within the home range (i.e., third order selection). Elk ( Cervus canadensis ) were reintroduced to southwestern Virginia, USA, from 2012 to 2014 following successful translocations onto reclaimed surface coal mines in the region. We sought to understand how elk have acclimated following their translocation using location data from GPS-collared adult female elk ( n = 33) collected from 2019 to 2022 along with remotely sensed terrain and land cover data. We utilized continuous-time movement models paired with generalized linear mixed-effects modeling to describe seasonal resource selection at second and third orders. At both scales of selection and throughout the year, female elk selected reclaimed surface mines, conifer forests, ridgetops, and areas with lower terrain roughness, while avoiding mixed hardwood and oak ( Quercus spp.) forests. Unmined open land was only selected at the third order during periods of forage scarcity (i.e., winter) and increased metabolic requirements (i.e., late gestation). Although surface coal mining leaves legacy environmental impacts on the landscape, management of these sites provides benefits to elk and maintains open habitat that is otherwise limited.

Virginia↗

USGS2026

Distribution and threats to the Arizona toad in Clark County

The Arizona Toad ( Anaxyrus microscaphus ) has been petitioned for protection under the U.S. Endangered Species Act (ESA) and is under evaluation for inclusion as a Covered Species under the Clark County Multi Species Habitat Conservation Plan Amendment (Clark County Department of Comprehensive Planning and USFWS, 2001; USFWS, 2015b). Although the species is locally abundant in some parts of its range, Arizona Toads have not been confirmed in Clark County since at least the 1980s. Extensive amphibian surveys in the late 1990s and examination of museum specimens reported no incidence of nonhybridized Arizona Toads in Clark County (Bradford et al., 2005), indicating a need to assess the current distribution of the species and availability of potential habitat for recovery efforts at the western extent of its historical range. This document reports on the results of 2 years of Clark County Desert Conservation Program (DCP) funding to assess the status of Arizona Toad populations in the study area. This project supports data collection for an ongoing Species Status Assessment for the Arizona Toad by the U.S. Fish and Wildlife Service (USFWS) and provides data to support management actions to create or preserve suitable habitat for the Arizona Toad on Clark County Riparian Reserve properties.

Nevada↗

USGS2026

Early Miocene volcanic rocks and associated tectonics, Lava Hills and southern Bristol Mountains, California

Volcanic rocks of latest Oligocene to early Miocene age form an east-west belt across part of the central eastern Mojave Desert from the Whipple Mountains on the east to the Rosamond Hills on the west. We term this the central belt because it is separated from northern and southern belts by swaths with no volcanic rocks. Limited geochronologic data indicate that much of the belt is latest Oligocene and early Miocene in age, about 24 to 19 Ma, a finding that is consistent with these rocks being overlain by the 18.8 Ma Peach Spring Tuff in many places. We describe Miocene geology in a central area of the belt, in the Lava Hills, southern Bristol Mountains, and southern Old Dad Mountains. Sedimentary basins formed coeval with early andesite to rhyolite volcanism, progressing from fluvial and lacustrine tuffaceous sandstone to volcanic lavas, tuffs, and breccias, indicating that early basins formed proximal to volcanic edifices. Higher strata are fluvial and lacustrine with lavas punctuating the sequence. Although basins may partly have been formed within topographic lows bounded by volcanic domes, plateaus, and stratovolcanoes, consistent stratigraphic sections over wide areas indicate that tectonic basin evolution affected broad areas. The volcanic section is capped by local basalt flows and the regional Peach Spring Tuff. Limited data on normal faults support interpretations of early extensional basin development caused by northeast-southwest oriented stretching. Later extension caused stratal rotations, tilting early deposits down to the southwest. This tilted and subsequently beveled basin architecture was overlain by the youngest volcanic deposits, primarily rhyolite and basalt. The Peach Spring Tuff, 18.8 Ma, lies within this upper unit. Similar stratigraphic and structural relations are exposed in the nearby Marble Mountains and Van Winkle Mountain sections, reinforcing that a broad area underwent similar volcanism and tectonism. In our study area the upper unit is only very gently tilted except near dextral strike-slip faults of the eastern California shear zone. These late Miocene to Recent faults are represented as four main fault zones spaced about 5 km apart, representing distributed shear north of the Bristol Lake basin.

California↗

USGS2026

Fisheries research and monitoring activities of the Lake Erie Biological Station, 2025

Lake Erie has the most populated watershed of all the Great Lakes and has undergone dramatic anthropogenic changes. Since the 1800s, overexploitation of fish populations, habitat destruction, non-native species proliferation, industrial contamination, and changes in nutrient loading have impacted the fish community including declines in or extirpation of many native species (Regier et al. 1969, Hartman 1973; Leach & Nepszy 1976; Ludsin et al. 2001). Implementation of the Clean Water Act and Great Lakes Water Quality Agreement in the 1970s improved habitat conditions (Reutter 2019), which contributed to several strong percid year-classes (Vandergoot et al. 2019). These strong year-classes also benefited from more restrictive management practices that reduced harvest, ultimately rehabilitating Lake Erie percid stocks (Kayle et al. 2015, STC 2020). Historically, Lake Erie supported a cool water fish community dominated by percids and salmonids. Recently updated FCOs set forth a vision that “Lake Erie will consist of diverse fish communities that support ongoing societal benefits, including thriving commercial and recreational fisheries, improved fish habitat and desirable ecosystem performance, and reduced adverse impacts from invasive fish” (Francis et al. 2020). Today, mixed fisheries resulting from seasonally changing cool and warm water habitats have developed in Lake Erie, and the new FCOs reflect a desire to manage both predator and prey fish communities within them. Although Lake Erie management agencies have traditionally focused on numerical indices of a few economically important species, aquatic ecosystem models are typically evaluated in terms of entire fish community biomass. As a result, our understanding of fish community structure and ecosystem dynamics from biomass-based models has been limited to short-term investigations and proxy measurements (e.g., length-weight conversion; FTG 2020). Therefore, many Lake Erie fish community databases are now incorporating biomass-based measurements. In response, USGS revised the Lake Erie trawl program to provide biomass-based measurements for all encountered species (Table 1). The survey design change occurred in 2012, coincident with commissioning of a new research vessel and a change in bottom trawl gear. These modifications already altered the existing time series; therefore, the survey design was also expanded to include greater spatial coverage and increased sample size generating a new time series. The purpose of this report is to develop a comprehensive understanding of the long-term changes and fish community dynamics including population dynamics of key fishes of interest to management agencies, such as native percids and their prey. Here, we summarize survey results for the most recent series of West Basin trawl data from 2013 through 2025. Note that a detailed description of the sampling process along with traditional numericallybased catch data (e.g., fish/ha) for individual species can be downloaded online (DuFour et al. 2026) or obtained for earlier years (https://doi.org/10.5066/F75M63X0; U.S. Geological Survey, Great Lakes Science Center 2019).

western Lake Erie↗

USGS2026

Chronic wasting disease reduces mule deer survival and hunter success in the Wind River Basin of Wyoming

Chronic wasting disease (CWD) is a fatal prion disease of cervids that has spread across much of North America and has recently become a global concern. Although CWD typically emerges gradually in new geographic regions, some areas experience rapid increases in prevalence for reasons that remain unclear. Herein, we describe the establishment of CWD in a mule deer (Odocoileus hemionus) population in the eastern portion of the Wind River Basin, WY, USA, where CWD prevalence in adult males (n=249) increased from 0% to 63% within a decade. We provide historical context, including a description of regional anthropogenic changes, and examine the epizootic’s impact on deer survival and hunting. From 2023 to 2025, we captured and monitored 96 adult mule deer. Annual survival was low: 0.38 for adult males (n=21) and 0.53 for adult females (n=75). Before CWD detection in 2012, mean hunter success was 72% (2000 to 2011). After detection, hunter success declined to 30% in 2022. We propose three hypotheses to explain the rapid rise in CWD prevalence, including food hotspots created by agriculture, increased agricultural dependency due to habitat degradation, and declining migratory behavior. Our case study highlights the potential effects of CWD and provides insights into possible drivers of transmission, to support more targeted management.

Wyoming↗

USGS2026

Creating usable science: A Southwest Climate Adaptation Science Center study

The southwestern United States consists of diverse ecosystems that are experiencing increasing pressures from rising temperatures, increasing aridity, and sea level rise. To prepare this region for future uncertainty, there is a need for strong partnerships among researchers and societal partners. The Southwest Climate Adaptation Science Center (SW CASC) acts to foster engaged scholarship from diverse perspectives to produce science relevant for management and policy decisions. Here, we synthesized a subset of SW CASC-funded projects and published manuscripts to illustrate how the combination of new scientific knowledge and the research and practice of engaged scholarship produce actionable science with direct societal impacts. In the SW CASC Contributions to Regional Science section, we touch on new research produced from funded projects on the most common topics: (1) Forest Ecosystems, (2) Coastal Ecosystems, (3) Hydrometeorology, and (4) Research on Engaged Scholarship. In the SW CASC Contributions to Regional Impacts section, we outline engaged scholarship activities to demonstrate how they created societal impacts: (1) the Keepers of the Flame course and workshops, (2) the Southwest Fire Climate Adaptation Partnership and the Southern California Montane Forests Project, (3) the Coastal Managers Workshop, (4) the Colorado River Basin Wiki, and (5) the Natural Resource Workforce Development Program. In the SW CASC Publications Cited in Policy section, we used a bibliometric analysis to assess the impact of the SW CASC-funded research on policy. We analyzed how often publications were used in policy documents, finding a citation rate of 27.6%. This is high compared to similar analyses that found peer-reviewed research articles cited at a rate of 3.9% in policy documents. We conclude that coproduced science makes unique and important contributions to the resilience of the Southwest, not only by generating new knowledge but by building capacity, creating lasting relationships, and informing policy and conservation and management decisions.

Arizona, California, Nevada, Utah↗

USGS2026

Investigating the influence of climate and volcanic surface aging on fluvial erosion: A case study of Réunion Island, Indian Ocean

Precipitation is one of the dominant drivers of landscape erosion and evolution; however, the effects of typical rainfall compared with less frequent, high-magnitude precipitation events on erosion remain unclear. Volcanic islands are ideal locations to study such phenomena due to their simple geometries, nontectonic construction, and strong spatiotemporal rainfall gradients. However, spatial variation in surface age, created during their construction, often complicates their degradation histories by introducing temporal changes in erosion rates as drainage networks develop. Réunion Island (western Indian Ocean) presents a clear example of this, with an east–west gradient in both surface age and mean annual precipitation, as well as infrequent cyclones that alter the background rainfall pattern. In this study, we analyze the effects of surface age, average rainfall, and rainfall variability on basin development and fluvial erosion across the island. We calculate basin-averaged values of basin morphology, age, precipitation, river discharge, eroded volumes, and erosion rates, and use these to analyze the dominant drivers of landscape evolution through a series of correlation analyses. Our results indicate a temporal dependence on the influence of precipitation, with young surfaces being dominantly eroded by high-rainfall events and older surfaces eroded by mean annual rainfall patterns. Furthermore, we show that drainage development of shield volcanoes follows similar trends to other volcano types, and suggest that surface permeability and groundwater structure are important controls on runoff-driven erosion on shield volcanoes. These results add new components to the question of how precipitation impacts erosion.

Réunion Island↗

USGS2026

Challenges and opportunities for national-scale projections of future coastal landscape change

Local to global scale projections of future coastal landscape change are essential to improve land and resource management decisions that aim to prepare for and reduce risk exposure to impending coastal hazards. However, the availability of actionable knowledge is often limited due to the complexity of drivers of change, their consequences, and uncertainties that span disciplines. Varying spatial and temporal scales of physical processes that occur on landscapes with differing levels of coastal development and modification complicate decision-making. This paper reviews advances in observational approaches, modeling, and quantification of uncertainty to support the next generation of coastal change projections. We also highlight transdisciplinary opportunities for making this information more accessible and useful to support decision-making in the coastal zone. This includes consideration of different levels of user engagement to address specific needs, as well as resources and mechanisms that can support knowledge transfer broadly. A central recommendation is the development of a coordinated framework to support research integration including three components: accounting for relevant drivers, processes, and feedbacks; working with users to identify their information needs; and generating meaningful projections and uncertainty. Actions that would support such frameworks include the evaluation of models through coordinated research approaches and multi-model comparisons; ongoing investments in observations and data-driven approaches necessary to understand this complex environment; expansion of modeling capabilities using novel techniques; prioritization of co-development efforts between researchers and users; and continued training and support for transdisciplinary research.

Alaska, California, Florida, New York↗

USGS2026

Determining Volcanic Risk in Auckland (DEVORA) Research Programme—A transdisciplinary approach to address the challenge of distributed volcanism in an urban environment

The Determining Volcanic Risk in Auckland (DEVORA) Research Programme was launched in 2008 to address the challenges associated with monogenetic volcanism in an urban setting and to enhance volcanic risk management in Tāmaki Makaurau Auckland in Aotearoa New Zealand. It is a multi-agency, increasingly transdisciplinary (defined here as research that transcends traditional disciplinary boundaries by integrating diverse types of knowledge, perspectives, and methods from academic and non-academic participants to create novel solutions to complex problems), and collaborative research program jointly led by Waipapa Taumata Rau University of Auckland and Earth Sciences New Zealand (ESNZ; formerly GNS Science), with core funding from Natural Hazards Commission Toka Tū Ake (NHC; formerly the Earthquake Commission, EQC) and Te Kaunihera o Tāmaki Makaurau Auckland Council (AC). The primary research focus of DEVORA is to investigate the geologic history, volcanic hazards, and risk posed by the basaltic intraplate Auckland Volcanic Field. Disruption from ash fall and gas from other Aotearoa New Zealand volcanoes is also considered. DEVORA’s work to explore exposure and vulnerability in Tāmaki Makaurau Auckland is also useful for assessing risks from other non-volcanic natural hazards, such as seismic and tsunami hazards. The greater Tāmaki Makaurau Auckland region has an ethnically and socio-economically diverse population of approximately 1.7 million, representing about one-third of the Aotearoa New Zealand population, and hosts critical infrastructure of national significance. The size and nature of the populace, consequential economic base, and important infrastructure within Tāmaki Makaurau Auckland mean that the effects of a volcanic eruption would be felt nationally, including through the disruption of air travel to Aotearoa New Zealand. The hazards from such an eruption could potentially affect hundreds of thousands of people, businesses, and lifelines (critical infrastructure). A considerable challenge for emergency and risk managers is the monogenetic nature of the volcanic field. It is not known where or when the next eruption will occur, how much warning we may get before an eruption, nor how an eruption and its effects might unfold. In this contribution, we highlight the concept and collaborative intent of the DEVORA Programme and show how it has evolved over the 16 years since its inception. We describe how DEVORA has unified more than 100 researchers (including more than 50 graduate students) and numerous stakeholders to address key issues facing Tāmaki Makaurau Auckland and describe how research findings are being implemented into policy and communicated to stakeholder agencies and the public. We also illustrate the broader influence of the DEVORA Programme and provide some learnings that might benefit others embarking on similar integrated projects, especially those focused on distributed volcanism in and near populated areas.

Auckland↗

USGS2026

Status and trends in the Lake Superior fish community, 2025

The U.S. Geological Survey has conducted annual trawl surveys across Lake Superior since 1978 that describe trends in fish species occurrence and relative abundance to support fisheries science and management. In 2025, the Lake Superior fish community was sampled with daytime bottom and surface trawls at 72 nearshore stations in May and June and 36 offshore locations in July. Nearshore bottom trawls collected 63,005 fish represented by 30 species or morphotypes. The number of species collected at each location ranged from 1 to 13, with a median of 7.0 species. Estimated fish biomass density at individual stations ranged from <0.1 to 125.7 kg per ha with a lakewide mean of 7.6 kg per ha. Offshore bottom trawls collected 30,342 fish represented by 13 species or morphotypes. Estimated fish biomass density at individual stations ranged from 1.6 to 34.7 kg per ha with a lakewide mean of 9.1 kg per ha, which was the highest since the offshore survey began in 2011. Lakewide average numerical densities (fish per ha) of age-1 fish were 0.67 per ha for Bloater, 0.01 per ha for Cisco, 1.15 per ha for Kiyi, 0.95 per ha for Lake Whitefish, and 336.33 per ha for Rainbow Smelt. Surface trawling collected 1,562 larval Coregonus individuals which was the fewest Coregonus larvae collected in a whole lake survey since the larval fish survey began in 2014. Nearshore mean larval Coregonus numerical densities were 156 fish per ha in May and June 2025 and 21 fish per ha in July 2025. May mean surface water temperatures (6.1°C) were near the warmest for the period-of-record, while June (6.8°C) and July (10.0°C) were near average or below.

Lake Superior↗