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At least 1,261 records · Page 70Linked to original sources
USGS2024

Examining inter-regional and intra-seasonal differences in wintering waterfowl landscape associations among Pacific and Atlantic flyways

The Central Valley of California (CVC) and Mid-Atlantic (MA) in the U.S. are both critical sites for nationwide food security (California Poultry Federation 2016, Prosser et al. 2017), and many waterfowl species annually, especially during the winter, providing feeding and roosting locations for a variety of species. Mapping waterfowl distributions, using NEXRAD, may aid in the adaptive management of important waterfowl habitat and allow various government agencies to better understand the interface between wild and domestic birds and commercial agricultural practices. We used 9 years (2014–2023) of data from the US NEXRAD network to model winter waterfowl relative abundance in the CVC and MA as a function of weather, temporal period, environmental conditions, and landcover characteristics using Boosted Regression Tree modelling. We were able to quantify the variability in effect size of 28 different covariates across space and time within two geographic regions which are critical to nationwide waterfowl management and host a high density of nationally important commercial agriculture. In general, weather, geographic (distance to features), and landcover condition (wetness index) predictors had the strongest relative effect on predicting wintering waterfowl relative abundance in both regions, while effects of land cover composition were more regionally and temporally specific. Increased daily mean temperature was a major predictor of increasing relative waterfowl abundance in both regions throughout the winter. Increasing precipitation had differing effects within regions, increasing relative waterfowl abundance in the MA, while decreasing in general within the CVC. Increasing relative waterfowl abundance in the CVC are strongly tied to the flooding of the landscape and rice availability, whereas waterfowl in the MA, where water is less limiting, are generally governed by waste grain availability and emergent wetland on the landscape. Waterfowl relative abundance in the MA was generally higher nearer to the Atlantic coast and lakes, while in the CVC they were higher nearer to lakes. Our findings promote a better understanding of spatial associations of waterfowl to landscape features and may aid in conservation and biosecurity management protocols.

Authorea↗
USGS1989

Retention and transport of nutrients in a third-order stream in northwestern California; hyporheic processes

Chloride and nitrate were coinjected into the surface waters of a third—order stream for 20 d to examine solute retention, and the fate of nitrate during subsurface transport. A series of wells (shallow pits) 0.5—10 m from the adjacent channel were sampled to estimate the lateral interflow of water. Two subsurface return flows beneath the wetted channel were also examined. The conservative tracer (chloride) was hydrologically transported to all wells. Stream water was >88% of flow in wells <4 m from the wetted channel. The lowest percentage of stream water was 47% at a well 10 m perpendicular to the stream. Retention of solutes was greater in the hyporheic zone than in the channel under summer low—flow conditions. Nominal travel time (the interval required for chloride concentration to reach 50% of the plateau concentration) was variable by well location, indicating different flow paths and presumably permeability differences in subsurface gravels. Nominal travel time was M 24 h for wells <5 m from the wetted channel. Coinjected nitrate was not conservative. Two wells were significantly (P < .05) higher in nitrate—N than would be predicted from chloride, while four were significantly lower. Wells 2.0—4.0 m from the wetted channel tended to have higher nitrate concentration than predicted, whereas nitrate sink locations tended to have transport distances >4.3 m. The capacity of the hyporheic zone for transient solute storage and as potential biological habitat varies with channel morphology, bed roughness, and permeability. A conceptual model that considers the groundwater—stream water interface as the fluvial boundary is proposed. Emerging paradigms of the riverine network should consider the hyporheic zone and associated nutrient cycling as an integral component of fluvial structure and function.

Ecology↗
USGS1996

Spatial partitioning of environmental correlates of avian biodiversity in the conterminous United States

Classification and regression tree (CART) analysis was used to create hierarchically organized models of the distribution of bird species richness across the conterminous United States. Species richness data were taken from the Breeding Bird Survey and were related to climatic and land use data. We used a systematic spatial grid of approximately 12,500 hexagons, each approximately 640 square kilometres in area. Within each hexagon land use was characterized by the Loveland et al. land cover classification based on Advanced Very High Resolution Radiometer (AVHRR) data from NOAA polar orbiting meteorological satellites. These data were aggregated to yield fourteen land classes equivalent to an Anderson level II coverage; urban areas were added from the Digital Chart of the World. Each hexagon was characterized by climate data and landscape pattern metrics calculated from the land cover. A CART model then related the variation in species richness across the 1162 hexagons for which bird species richness data were available to the independent variables, yielding an R2-type goodness of fit metric of 47.5% deviance explained. The resulting model recognized eleven groups of hexagons, with species richness within each group determined by unique sequences of hierarchically constrained independent variables. Within the hierarchy, climate data accounted for more variability in the bird data, followed by land cover proportion, and then pattern metrics. The model was then used to predict species richness in all 12,500 hexagons of the conterminous United States yielding a map of the distribution of these eleven classes of bird species richness as determined by the environmental correlates. The potential for using this technique to interface biogeographic theory with the hierarchy theory of ecology is discussed. ?? 1996 Blackwell Science Ltd.

Biodiversity Letters↗
USGS1999

Water and sediment characteristics associated with avian botulism outbreaks in wetlands

Avian botulism kills thousands of waterbirds annually throughout North America, but management efforts to reduce its effects have been hindered because environmental conditions that promote outbreaks are poorly understood. We measured sediment and water variables in 32 pairs of wetlands with and without a current outbreak of avian botulism. Wetlands with botulism outbreaks had greater percent organic matter (POM) in the sediment (P = 0.088) and lower redox potential in the water (P = 0.096) than paired control wetlands. We also found that pH, redox potential, temperature, and salinity measured just above the sediment-water interface were associated (P ≤ 0.05) with the risk of botulism outbreaks in wetlands, but relations were complex, involving nonlinear and multivariate associations. Regression models indicated that the risk of botulism outbreaks increased when water pH was between 7.5 and 9.0, redox potential was negative, and water temperature was >20°C. Risk declined when redox potential increased (>100), water temperature decreased (10-15°C), pH was <7.5 or >9.0, or salinity was low (<2.0 ppt). Our predictive models could allow managers to assess potential effects of wetland management practices on the risk of botulism outbreaks and to develop and evaluate alternative management strategies to reduce losses from avian botulism.

Journal of Wildlife Management↗
USGS1963

Hypervelocity impact of steel into Coconino Sandstone

Impact of a 0.4019-g steel sphere at 4.27 km/sec into Coconino Sandstone [Permian] from Meteor Crater, Arizona, produced a crater 11-12 cm across and 2.45 cm deep. The ejecta consist of sandstone fragments, disaggregated sand, splinters of sand grains, strongly shocked aggregates of crushed sandstone grains, and chips, splinters, small amounts of silica glass, and minute spheres of steel. Part of the shocked steel was melted, and some of the melted and unmelted steel occurs as impregnations in the strongly shocked sandstone. Small amounts of glass, which were produced by shock from the sandstone, were found. The fusion of the steel cannot be due to compressive heating alone but can be partly accounted for by conduction of heat from the shocked sandstone and by production of heat by viscous drag and friction along the sandstone-projectile interface and along shear planes in the projectile.

Arizona↗
USGS2022

Great Lakes spatial priorities study

Spatial data about the bathymetry, habitat characteristics, underlying geology, and other features of the ocean and inland seas are essential for decision-making. Marine research and management organizations use these data to help ensure safe navigation, promote sustainable fisheries, extract energy, and protect marine habitats in the coastal and ocean waters of the U.S. Exclusive Economic Zone (EEZ) and Laurentian Great Lakes. Many of these organizations may have overlapping or shared mapping interests without knowing it. In a multi-jurisdictional planning environment, it can be challenging and cumbersome to determine where other entities have shared or overlapping mapping interests, especially across a transnational region such as the Great Lakes. State and provincial governments, federal governments, academia, tribes and First Nations, and other stakeholders from both the U.S. and Canada all have mapping interests across Great Lakes waters. Identifying and communicating target geographies for new data collection that are shared among multiple organizations can both help to avoid redundancy of new mapping efforts, and create opportunities for greater efficiency through collaboration. To address this issue, a spatial priorities study was conducted using a geospatial tool developed by the National Ocean Services National Centers for Coastal and Ocean Science (NCCOS). The tool provided an easy-to-use online interface in which programs can identify their priorities in a simple and straightforward way. This study asked representatives of Great Lakes management and science organizations to identify the areas for which they needed maps of lakebed features on a near-term, mid-term, and long-term timeframe, and why. Then, the responses were analyzed and overlaid to determine areas of shared mapping need and opportunity and to determine the types of map products needed. The analysis revealed high interest among multiple organizations in discrete geographies including the Minnesota and Wisconsin shoreline from Duluth to the eastern extent of the Bayfield Peninsula, Green Bay in Lake Michigan, and the southern coastlines of Lake Erie and Lake Ontario, the St. Marys River, and the northern Lake Superior coastal waters near Grand Portage, MN. Lower priority mapping interest were distributed widely across all lakes, but tended to be concentrated in nearshore areas (<30 m depth). The analysis also indicated that the top mapping justifications were Habitat/biota/natural area, Benthic exploration, Commercial and recreational fishing, and Scientific research. The top desired map product types were Elevation, Substrate/sub-bottom geologic characterization, and Habitat map/characterization, although participants on some lakes noted other less prevalent product types. Following from previously conducted NOAA and non-NOAA Federal spatial prioritization exercises, the results of this regional focus can help mapping organizations better understand how their priorities align with the needs of regional organizations, allow for more efficient coordination and funding, and enable partners to leverage assets and resources to fill their most pressing data and information gaps across Great Lakes waters. The U.S. Mapping Coordination Site hosts the results of this study and other spatial prioritization studies. Through this website, one can interact with the study results along with recent and planned mapping efforts. NOAA intends to update their spatial priorities on a three- to five-year basis. Future studies should strive to expand participation of federal agencies, state and local governments, federally-recognized tribes, academia, and private industry (among other stakeholders) to seek out ocean mapping partnerships in conjunction with the National Ocean Mapping, Exploration and Characterization (NOMEC) goals map once, use many times.”

Great Lakes↗
USGS2021

A rapid assessment function to estimate common raven population densities: Implications for targeted management

Common raven ( Corvus corax ; raven) populations have increased over the past 5 decades within the western United States. Raven population increases have been largely attributed to growing resource subsidies from expansion of human enterprise. Concomitantly, managers are becoming increasingly concerned about elevated adverse effects on multiple sensitive prey species, damage to livestock and agriculture, and human safety. Managers could benefit from a rapid but reliable method to estimate raven densities across spatiotemporal scales to monitor raven populations more efficiently and inform targeted and adaptive management frameworks. However, obtaining estimates of raven density is data- and resource-intensive, which renders monitoring within an adaptive framework unrealistic. To address this need, we developed a rapid survey protocol for resource managers to estimate site-level density based on the average number of ravens per survey. Specifically, we first estimated raven densities at numerous field sites with robust distance sampling procedures and then used regression to investigate the relationship between those density estimates and the number of ravens per survey, which revealed a strong correlation ( R 2 = 0.86). For management application, we provide access to R function software through a web-based interface to estimate density using number of ravens per survey, which we refer to as a Rapid Assessment Function (RAF). Then, using a simulation analysis of data from sites with abundant surveys and the RAF, we estimated raven density based on different numbers of surveys to help inform how many surveys are needed to achieve reliable estimates within this rapid assessment. While more robust procedures of distance sampling are the preferred methods for estimating raven densities from count surveys, the RAF tool presented herein provides a reliable approximation for informing management decisions when managers are faced with resource and small sample size constraints.

California, Idaho, Nevada, Oregon↗
USGS2026

CRESCENT earthquake dynamic rupture, earthquake cycle, and tsunami code verification platform

Physics-based simulations are critical for understanding natural hazards. The increasing complexity of numerical codes requires benchmark exercises to verify that different computational methods yield consistent results when solving the same governing equations. Here, we present an open-access web platform designed for the verification of earthquake dynamic rupture, seismic cycle, and tsunami simulations. The platform architecture utilizes a modular, serverless backend on Amazon Web Services (AWS) to provide scalable file processing and visualization. A lightweight static web application provides a secure interface for uploading and managing results, while the browser-based data visualization enables interactive analysis of time series and surface grid data. By using structured JavaScript Object Notation (JSON) text files to define benchmark structures, the system remains fully extensible, allowing the addition of new scenarios without modifying the underlying software logic. The platform hosts the "The Tsunami Problem Versions" (TTPV) 1 & 2, two benchmarks for 3D fully coupled earthquake dynamic rupture and tsunami generation, and provides a framework for earthquake cycle models. This community resource aims to build trust in numerical simulations and facilitate long-term collaborative code verification as modeling software continues to evolve.

Seismica↗
USGS2013

Fire history, effects and management in southern Nevada

Fire can be both an ecosystem stressor (Chapter 2) and a critical ecosystem process, depending on when, where, and under what conditions it occurs on the southern Nevada landscape. Fire can also pose hazards to human life and property, particularly in the wildland/urban interface (WUI). The challenge faced by land managers is to prevent fires from occurring where they are likely to threaten ecosystem integrity or human developments, while allowing fires to occur where they will provide ecosystem benefits. The Southern Nevada Agency Partnership (SNAP) Science and Research Strategy summarizes this desired outcome with Sub-goal 1.1, which is to manage wildland fire to sustain Southern Nevada’s ecosystems (table 1.3; Chapter 1). This chapter provides information that will help land managers develop strategies to achieve this goal. It begins with a background section on fire history, spatial and temporal patterns of fire, and fire effects for the major ecosystem types of southern Nevada, (table 1.1; Chapter 1). Potential fire management actions are then discussed, the overall implications of the information to fire management are summarized, and the major knowledge gaps are described.

Nevada↗
USGS2021

Living with wildfire in Chalk Creek, Chaffee County, Colorado: 2019 data report

Wildfire affects many types of communities and is a particular concern for communities in the wildland urban interface (WUI), such as Chalk Creek in Chaffee County. The core intent of this project was to provide evidence to support Colorado State Forest Service (CSFS) Salida Field Office’s wildfire mitigation and education program. This report analyzes existing wildfire risk data collected in late 2017 through 2019 and pairs it with social data collected in the summer of 2019, in order to better understand Chalk Creek residents’ knowledge, experiences, and perceptions about wildfire risk. This greater understanding will help CSFS focus its programs and outreach and ultimately promote increased mitigation and reduced wildfire risk in Chalk Creek.

Colorado↗
USGS2022

Living with wildfire in Teton County, Wyoming: 2021 data report

Wildfire affects many types of communities and is a particular concern for communities in the wildland urban interface (WUI), such as those of Teton County, Wyoming. The core intent of this project was to provide evidence to support the Teton Area Wildfire Protection Coalition (TAWPC) and affiliated organizations in their wildfire mitigation and education programming. This report analyzes existing wildfire risk data collected in fall 2020 and pairs it with social data collected in the winter and spring of 2021, in order to better understand residents’ knowledge, experiences, and perceptions about wildfire risk. This greater understanding will help TAWPC focus its programs and outreach and ultimately promote increased mitigation and reduced wildfire risk in Teton County. The results of the wildfire risk assessment, covering 725 private residential properties in the study area, suggest that 89% face high, very high, or extreme risk of wildfire. In comparison, only 41% of residents estimated their risk of wildfire to be high, very high, or extreme. This suggests a “gap” between rapid assessment and survey estimates.

Wyoming↗
USGS2022

Living with wildfire in Grand County, Colorado: 2021 data report

Wildfire affects hundreds of wildland-urban interface communities each year, and yet most communities lack data reflecting the conditions before an event. This study was conducted before the devastating 2020 East Troublesome Fire1, which spread across 193,812 acres and resulted in two lives lost and 366 homes and 214 other structures burned. The fire’s dramatic run threatened over 7,000 structures and led to a mandatory evacuation of over 35,000 people in Grand and Larimer Counties. The data reported here serve as baseline data to aid in understanding the parcel and social conditions before the fire. This report presents results from WiRē Rapid Wildfire Risk Assessment (WiRē RA) data, collected from 1,162 private residential properties in six communities in five fire protection districts (FPDs), the majority (72%) of which were characterized as high, very high, or extreme risk. This report also presents results from household surveys sent to homeowners in the study area. Household survey respondents underestimated their risk compared to the conditions observed through the professional risk assessment. Respondents consistently overestimated the amount of defensible space and the distance from their homes to nonvegetative combustibles. Respondents also overestimated the availability of driveway clearance that would enable access for response vehicles and for safe passing of residents evacuating and responders arriving to their homes.

Colorado↗
USGS2023

Living with wildfire in Park County, Colorado 2021 data report

Wildfire affects many types of communities and is a particular concern for communities in the wildland urban interface (WUI), such as those of Park County, Colorado. The core intent of this project was to provide evidence to support the Platte Canyon Fire Protection District (PCFPD) and Fire Adapted Bailey in their wildfire mitigation and education programming. This report describes wildfire risk data collected in fall 2020 and pairs it with social data collected in the fall and winter of 2020-2021, in order to better understand residents’ knowledge, experiences, and perceptions about wildfire risk in the communities of the Burland Ranchettes Homeowners Association (HOA) area and surrounding neighborhoods. This greater understanding will help PCFPD focus its programs and outreach and ultimately promote increased mitigation and reduced wildfire risk in Park County.

Colorado↗
USGS2023

Living with wildfire in Emigration Canyon, Utah: 2022 data report

Located in North Central Utah, Emigration Canyon is a prominent and historic canyon that runs northeast from Salt Lake City into the higher elevations of the Wasatch Mountains. The Wasatch Range is characterized by steep, rocky slopes and 26-44 millimeters of annual rainfall, both of which contribute to a high threat of wildfire. The area’s landscape is diverse with oak woodland at the lower elevations up to a conifer forest type including ponderosa pine, Douglas-fir, and subalpine fir. The Utah Wildfire Risk Assessment Portal (UWRAP) rates the fire danger in Emigration Canyon as “Extreme.” Resultantly, the Utah Division of Forestry, Fire & State Lands, as well as adjacent land management agencies, have identified this wildland-urban interface (WUI) zone as a high priority. The Utah Division of Forestry, Fire & State Lands website describes WUI as “the zone where structures and other human development meet and intermingle with undeveloped wildland or vegetative fuels.”

Utah↗
USGS1974

Red Sea geochemistry

The Red Sea drillings reveal a number of new facets of the hot-brine-metalliferous system and other geochemical aspects of the sea, its sediments, and its past history as follows: 1) Dark shales rich in organic material, and containing enhanced Mo and V concentrations, are characteristic of Plio-Pleistocene strata in the Red Sea. Values as high as 1500 ppm V and 500 ppm Mo were obtained in sediments containing up to 8 percent organic carbon. 2) Metalliferous sediments in the hot brine deep (Site 226) are similar in composition in both solids and interstitial water to previously analyzed sediments. However, one site (228) well south of the known hot-brine deeps shows zinc mineralization reaching 5 percent Zn in late Miocene shale-anhydrite breccias. 3) Pore fluid studies show that near-saturated (NaCl) brines having similar total salt concentration to the hot-brine fluids are associated with Miocene evaporites at Sites 225, 227, and 228. However, their chemical and isotopic composition precludes such fluids being part of the "hot brine plumbing system." Hydrogen and oxygen isotope studies demonstrate that fluids trapped between and among the evaporitic rocks have a strong meteoric water component, presumed to have entered the rocks during or shortly after formation in shallow evaporating pans. The composition of pore fluid at Site 227 suggests the presence of late-stage evaporite minerals of the tachyhydrite CaMg 2 Cl 6 • 12H 2 O series in the in situ rocks. 4) Diffusivity measurements show that the pre-Miocene strata permit dissolved salt or gas diffusion to the extent of from 1/2 to about 1/10 the rate in free solution. However, in anhydrites diffusivity is reduced more than 100-fold, and no diffusion could be detected through halite rock. The rates applied to interstitial salt gradients at Site 225 suggest that less than 1 meter of rock salt is removed per million years by diffusion processes. The diffusion of salt can already be detected a few meters below the sediment-water interface, and based on the interstitial water studies, one can affirm the presence of salt at depth at Sites 228, 230, and possibly 229, where rock salt was not encountered by the drill. 5) Isotopic measurements on leads show that both leads from Site 228 and the hot brine deep (Site 226) require input from igneous or volcanic sources (e.g., volcanic ash). Elsewhere, however, leads of sedimentary-pelagic origin are noted. 6) Isotopic and other evidence indicates that the long-distance transport of subterranean brines advocated by Craig (1969) is unlikely. Instead, it is proposed that the source of the hot brines is subevaporite clastic or other aquifers of early to middle Miocene age that have been disrupted by rifting. These discharge in the deeps by virtue of hydrodynamic continuity with heavy brines at higher positions on the nearby flanks of the Red Sea. In this case, the waters might be fossil (middle Miocene) Red Sea waters of relatively normal salinity that have acquired greater salt concentration by diffusion from overlying late Miocene evaporites. The model is consistent with the isolated nature of the brine deeps and suggests that flow might have been enhanced by increased hydraulic gradients during periods of lowered Red Sea levels. 7) Interstitial water evidence indicates that Pleistocene lowerings of sea level did not cause evaporative conditions leading to actual gypsum or other evaporite deposition in the deeper water zones, as has been postulated. This in turn suggests that sill depths were greater than have been assumed.

Initial reports of the Deep Sea Drilling Project↗
USGS1985

Environmental trends among Neogene benthic foraminifers at Deep Sea Drilling Project Site 548, Irish continental margin

An analysis of diversity and abundance trends among all benthic foraminiferal genera and species, and particularly among species of Bolivina, was carried out for 59 samples of Neogene sediment from DSDP-IPOD Site 548, Goban Spur. By correlating these census data with lithological, geophysical, geochemical, and other faunal and floral measurements in the same stratigraphic interval, a record of irregularly fluctuating cycles was compiled. We interpret them as indicators of relative sea level. High sea levels are characterized by pelagic sedimentation and by high generic and total species diversities. During low sea level, diversity values were lower, and the accumulation of terrigenous detritus was more prevalent at the site. A sequence recording five highstands and five lowstands is interrupted by four unconformities in a scenario remarkably similar to that postulated in the work of P. R. Vail and his colleagues. Bolivina species diversity also varied cyclically. We interpret diversity of Bolivina species as a measure of relative oxygen and nutrient content at the water/sediment interface; high diversity indicates the presence of an oxygen-minimum layer, accompanied by nutrient enrichment. Our data show that this property generally varied directly with sea level, but sometimes varied independently.

Initial reports of the Deep Sea Drilling Project↗
USGS2006

Data Report: Acetate and Hydrogen Concentrations in Pore Fluids Associated with a Large Gas Hydrate Reservoir, Southern Hydrate Ridge, offshore Oregon, USA

Acetate and hydrogen concentrations in pore fluids were measured in samples taken at seven sites from southern Hydrate Ridge (SHR) offshore Oregon, USA. Acetate concentrations ranged from 3.17 to 2515 µM. The maximum acetate concentrations occurred at Site 1251, which was drilled on a slope basin to the east of SHR at depths just above the bottom-simulating reflector (BSR) that marks the boundary of gas hydrate stability. Acetate maxima and localized high acetate concentrations occurred at the BSR at all sites and frequently corresponded with areas of gas hydrate accumulation, suggesting an empirical relationship. Acetate concentrations were typically at a minimum near the seafloor and above the sulfate/methane interface, where sulfate-reducing bacteria may consume acetate. Hydrogen concentrations in pressure core samples ranged from 16.45 to 1036 parts per million by volume (ppmv). In some cases, hydrogen and acetate concentrations were elevated concurrently, suggesting a positive correlation. However, sampling of hydrogen was limited in comparison to acetate, so any relationships between the two analytes, if present, were difficult to discern.

Oregon↗
USGS2021

Anthropogenic edge effects in habitat selection by sun bears in a protected area

Wildlife populations in southeast Asia are increasingly experiencing a broad array of anthropogenic threats, and mammalian carnivores are particularly vulnerable. Populations of the Malayan sun bear Helarctos malayanus are estimated to have declined by 30% over the last 30 years from forest conversion to industrial plantations and mortality associated with human–bear conflicts and illegal wildlife trade. However, the effects of industrial plantations on habitat selection and activity patterns of mammals that live at the protected area-plantation interface, including sun bears, are not well known. We investigated habitat selection and activity patterns of sun bears in Tabin Wildlife Reserve in Sabah, Malaysia. We deployed 83 remote camera sites to record sun bear detections during two sampling periods (2012–2013 and 2017). We used generalized linear models to examine relationships between sun bear presence and site covariates representing physical, environmental and anthropogenic elements of the landscape. Relative probability of sun bear presence was positively associated with distance to roads and elevation. Because most roads were on the reserve boundary and often associated with oil palm plantations, proximity to roads likely served as a surrogate measure of human accessibility and activity in peripheral areas of the reserve. Supporting that interpretation, sun bears close to the reserve boundary were primarily active at night, whereas daytime activity was more common for bears in the interior. Our findings indicate that sun bears alter behaviour and habitat selection likely in response to anthropogenic activities at the edges of Tabin Wildlife Reserve (112 200 ha). Because the ratio of edge to interior increases steeply with declining habitat area, smaller protected areas bordered by plantations are predicted to have greater impacts on sun bear behaviour and, potentially, population persistence. Effective conservation actions may benefit from management to improve the security of edge habitats for sun bears and other vulnerable species.

Tabin Wildlife Reserve↗