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At least 1,063 records · Page 59Linked to original sources
USGS2014

Disease and community structure: white-nose syndrome alters spatial and temporal niche partitioning in sympatric bat species

Aim Emerging infectious diseases present a major perturbation with apparent direct effects such as reduced population density, extirpation and/or extinction. Comparatively less is known about the potential indirect effects of disease that likely alter community structure and larger ecosystem function. Since 2006, white-nose syndrome (WNS) has resulted in the loss of over 6 million hibernating bats in eastern North America. Considerable evidence exists concerning niche partitioning in sympatric bat species in this region, and the unprecedented, rapid decline in multiple species following WNS may provide an opportunity to observe a dramatic restructuring of the bat community. Location We conducted our study at Fort Drum Army Installation in Jefferson and Lewis counties, New York, USA, where WNS first impacted extant bat species in winter 2007–2008. Methods Acoustical monitoring during 2003–2011 allowed us to test the hypothesis that spatial and temporal niche partitioning by bats was relaxed post-WNS. Results We detected nine bat species pre- and post-WNS. Activity for most bat species declined post-WNS. Dramatic post-WNS declines in activity of little brown bat ( Myotis lucifugus , MYLU), formerly the most abundant bat species in the region, were associated with complex, often species-specific responses by other species that generally favoured increased spatial and temporal overlap with MYLU. Main conclusions In addition to the obvious direct effects of disease on bat populations and activity levels, our results provide evidence that disease can have cascading indirect effects on community structure. Recent occurrence of WNS in North America, combined with multiple existing stressors, is resulting in dramatic shifts in temporal and spatial niche partitioning within bat communities. These changes might influence long-term population viability of some bat species as well as broader scale ecosystem structure and function.

New York↗
USGS2015

Establishing conservation baselines with dynamic distribution models for bat populations facing imminent decline

Aim Bat mortality rates from white-nose syndrome and wind power development are unprecedented. Cryptic and wide-ranging behaviours of bats make them difficult to survey, and population estimation is often intractable. We advance a model-based framework for making spatially explicit predictions about summertime distributions of bats from capture and acoustic surveys. Motivated by species-energy and life-history theory, our models describe hypotheses about spatio-temporal variation in bat distributions along environmental gradients and life-history attributes, providing a statistical basis for conservation decision-making. Location Oregon and Washington, USA. Methods We developed Bayesian hierarchical models for 14 bat species from an 8-year monitoring dataset across a ~430,000 km 2 study area. Models accounted for imperfect detection and were temporally dynamic. We mapped predicted occurrence probabilities and prediction uncertainties as baselines for assessing future declines. Results Forest cover, snag abundance and cliffs were important predictors for most species. Species occurrence patterns varied along elevation and precipitation gradients, suggesting a potential hump-shaped diversity–productivity relationship. Annual turnover in occurrence was generally low, and occurrence probabilities were stable among most species. We found modest evidence that turnover covaried with the relative riskiness of bat roosting and migration. The fringed myotis ( Myotis thysanodes ), canyon bat ( Parastrellus hesperus ) and pallid bat ( Antrozous pallidus ) were rare; fringed myotis occurrence probabilities declined over the study period. We simulated anticipated declines to demonstrate that mapped occurrence probabilities, updated over time, provide an intuitive way to assess bat conservation status for a broad audience. Main conclusions Landscape keystone structures associated with roosting habitat emerged as regionally important predictors of bat distributions. The challenges of bat monitoring have constrained previous species distribution modelling efforts to temporally static presence-only approaches. Our approach extends to broader spatial and temporal scales than has been possible in the past for bats, making a substantial increase in capacity for bat conservation.

Oregon, Washington↗
USGS2018

Phylogeny and species traits predict bird detectability

Avian acoustic communication has resulted from evolutionary pressures and ecological constraints. We therefore expect that auditory detectability in birds might be predictable by species traits and phylogenetic relatedness. We evaluated the relationship between phylogeny, species traits, and field‐based estimates of the two processes that determine species detectability (singing rate and detection distance) for 141 bird species breeding in boreal North America. We used phylogenetic mixed models and cross‐validation to compare the relative merits of using trait data only, phylogeny only, or the combination of both to predict detectability. We found a strong phylogenetic signal in both singing rates and detection distances; however the strength of phylogenetic effects was less than expected under Brownian motion evolution. The evolution of behavioural traits that determine singing rates was found to be more labile, leaving more room for species to evolve independently, whereas detection distance was mostly determined by anatomy (i.e. body size) and thus the laws of physics. Our findings can help in disentangling how complex ecological and evolutionary mechanisms have shaped different aspects of detectability in boreal birds. Such information can greatly inform single‐ and multi‐species models but more work is required to better understand how to best correct possible biases in phylogenetic diversity and other community metrics.

Ecography↗
USGS2025

Does habitat or climate change drive species range shifts?

A primary prediction of climate change ecology is that species will track their climate niche poleward and upslope. However, studies have shown species responding in surprising ways. In this study, we aim to understand the impact of global change on species ranges by considering both climate and habitat changes. Using occupancy analysis of acoustic survey data in the mountains of the northeastern United States, we tested specific predictions of range responses to warming (shifting upslope), precipitation change (shifting downslope), and forest composition change (shifting downslope). We found that American red squirrels Tamiasciurus hudsonicus , key nodes in northern North American food webs, are not tracking increasing temperatures upslope, despite substantial warming in recent decades. Structural equation modeling indicates that red squirrel abundance is primarily influenced by red-spruce forest cover, which has shifted downslope with recovery from historical logging and acid deposition. Accounting for the multiple dimensions of global change will enable better predictions and more effective conservation strategies.

Connecticut, Maine, Massachusetts, New Hampshire, ↗
USGS2015

Sex-biased survivorship and differences in migration of wild steelhead (Oncorhynchus mykiss) smolts from two coastal Oregon rivers

In salmonids with partial migration, females are more likely than males to undergo smoltification and migrate to the ocean (vs. maturing in freshwater). However, it is not known whether sex affects survivorship during smolt migration (from fresh water to entry into the ocean). We captured wild steelhead ( Oncorhynchus mykiss) smolts in two coastal Oregon rivers (USA) and collected fin tissue samples for genetic sex determination (2009; N = 70 in the Alsea and N = 69 in the Nehalem, 2010; N = 25 in the Alsea). We implanted acoustic tags and monitored downstream migration and survival until entry in to the Pacific Ocean. Survival was defined as detection at an estuary/ocean transition array. We found no effect of sex on smolt survivorship in the Nehalem River in 2009, or in the Alsea River in 2010. However, males exhibited significantly lower survival than females in the Alsea River during 2009. Residency did not influence this result as an equal proportion of males and females did not reach the estuary entrance (11% of males, 9% of females). The sexes did not differ in timing or duration of migration, so those variables seem unlikely to explain sex-biased survivorship. Larger males had higher odds of survival than smaller males in 2009, but the body size of females did not affect survivorship. The difference in survivorship between years in the Alsea River could be due to flow conditions, which were higher in 2010 than in 2009. Our findings suggest that sex may affect steelhead smolt survival during migration, but that the difference in survivorship may be weak and not a strong factor influencing adult sex ratios.

Oregon↗
USGS2016

Do intracoelomic telemetry transmitters alter the post-release behaviour of migratory fish?

Electronic tags have become a common tool in fish research, enhancing our understanding of how fish interact with their environment and move among different habitats, for estimating mortality and recording internal physiological states. An often-untested assumption of electronic tagging studies is that tagged fish are representative of untagged conspecifics and thus show ‘normal’ behaviour (e.g. movement rates, swimming activity, feeding). Here, we use a unique data set for potamadromous walleye (Sander vitreus) in Lake Huron and Lake Erie tributaries to assess whether the lack of appropriate controls in electronic tagging could seriously affect behavioural data. We used fish tagged in previous years and compared their migratory behaviour during the spawning season to fish tagged in a current year at the same location. The objective of the study was to determine whether intracoelomic acoustic tag implantation altered downstream movement of walleye after spawning. Fish tagged in a given season travelled slower downstream from two river spawning sites than fish tagged in previous years. Fish tagged one or two years earlier showed no differences between each other in downstream travel time, in contrast to fish tagged in a given year. Our results support notions that standard collection and intracoelomic tagging procedures can alter short-term behaviour (i.e. days, weeks, months), and as such, researchers should use caution when interpreting data collected over such time periods. Further, whenever possible, researchers should also explicitly evaluate post-tagging effects on behaviour as part of their experimental objectives.

Maumee Bay, Saginaw Bay↗
USGS2017

Spawning site fidelity and apparent annual survival of walleye (Sander vitreus) differ between a Lake Huron and Lake Erie tributary

Fidelity to spawning habitats can maximise reproductive success of fish by synchronising movements to sites of previous recruitment. To determine the role of reproductive fidelity in structuring walleye Sander vitreus populations in the Laurentian Great Lakes, we used acoustic telemetry combined with Cormack–Jolly–Seber capture–recapture models to estimate spawning site fidelity and apparent annual survival for the Tittabawassee River in Lake Huron and Maumee River in Lake Erie. Walleye in spawning condition were tagged from the Tittabawassee River in Lake Huron and Maumee River in Lake Erie in 2011–2012. Site fidelity and apparent annual survival were estimated from return of individuals to the stream where tagged. Site fidelity estimates were higher in the Tittabawassee River (95%) than the Maumee River (70%) and were not related to sex or fish length at tagging. Apparent annual survival of walleye tagged in the Tittabawassee did not differ among spawning seasons but was higher for female than male walleye and decreased linearly as fish length increased. Apparent annual survival of walleye tagged in the Maumee River did not differ among spawning seasons but was higher for female walleye than male walleye and increased linearly as fish length increased. Greater fidelity of walleye tagged in the Tittabawassee River than walleye tagged in the Maumee River may be related to the close proximity to the Maumee River of other spawning aggregations and multiple spawning sites in Lake Erie. As spawning site fidelity increases, management actions to conserve population structure require an increasing focus on individual stocks.

Lake Erie, Lake Huron↗
USGS2018

Multiple metrics provide context for the distribution of a highly mobile fish predator, the blue catfish

Data sets with increased spatial and temporal resolution can help researchers and resource managers quantify representative distributional patterns of mobile sportfish. In this research, first, we illustrate patterns of sportfish distribution using individual ( percent of population, residence time, number of movements ) and combined distributional metrics. Second, we apply these metrics to one highly mobile fish species, the blue catfish ( Ictalurus furcatus ), across a range of spatial (whole reservoir, region, site) and temporal (year, month, diel period) scales. Specifically, we tracked 123 acoustically tagged blue catfish with a 20-receiver array in Milford Reservoir, KS, USA. When we integrated metrics, four site-specific distributional patterns emerged: (a) a large, active multi-site fish aggregation, (b) localised site fidelity, (c) transitional sites and (d) rarely used locations. These patterns would not have been detected using a single metric as each measurement revealed a different piece of the distribution story. For example, if we had only quantified percent of population, we could identify fish location, but not whether individual fish spent time at a location or were just passing through. Our examination of multiple scales also provided a novel context for interpreting site-specific patterns. As an illustration of this insight, using conventional approaches, we would have observed heterogeneity, but we would not have detected fish aggregations, in which individual fish either remained or repeatedly returned to a site. In summary, our results show the advantage of setting the entire ecosystem as the study boundary to integrate multiple responses using a spatially and temporally extensive data set.

Kansas↗
USGS2026

A conceptual framework and methods for studying the connectivity of fishes

Connectivity is a multifaceted concept that has important implications for the management and conservation of marine and freshwater fishes. We developed a conceptual framework that encompasses multiple, interrelated categories of connectedness, including landscape (e.g., structural, functional) connectivity and ecological (e.g., trophic, genetic, demographic) connectivity, that together shape the flow of organisms, energy and information across ecosystems. We also synthesised six key methods that can be used to study connectivity of fishes: (1) telemetry, including satellite, acoustic, radio and passive integrated transponders (PIT), (2) mark-recapture, (3) environmental tracers, including stable isotopes and otolith-microchemistry, (4) genetics, (5) community structure analysis and (6) emerging technologies and tools (e.g., remote sensing and artificial intelligence). For each method, we describe the categories of connectivity it can assess and provide real-world examples where they have been effectively used. We also identify limitations of each method. This article highlights the diverse and evolving toolbox of methods used to assess fish connectivity, underscoring the need for continued collaboration, innovation and integration of new approaches to refine our understanding and address remaining challenges in this critical area of aquatic ecology and fisheries management.

Fish and Fisheries↗
USGS2024

Utility of an instantaneous salt dilution method for measuring streamflow in headwater streams

Streamflow records are biased toward large streams and rivers, yet small headwater streams are often the focus of ecological research in response to climate change. Conventional flow measurement instruments such as acoustic Doppler velocimeters (ADVs) do not perform well during low-flow conditions in small streams, truncating the development of rating curves during critical baseflow conditions dominated by groundwater inflow. We revisited an instantaneous solute tracer injection method as an alternative to ADVs based on paired measurements to compare their precision, efficiency, and feasibility within headwater streams across a range of flow conditions. We show that the precision of discharge measurements using salt dilution by slug injection and ADV methods were comparable overall, but salt dilution was more precise during the lowest flows and required less time to implement. Often, headwater streams were at or below the depth threshold where ADV measurements could even be attempted and transects were complicated by coarse bed material and cobbles. We discuss the methodological benefits and limitations of salt dilution by slug injection and conclude that the method could facilitate a proliferation of streamflow observation across headwater stream networks that are highly undersampled compared to larger streams.

Virginia↗
USGS2010

Diversity in destinations, routes and timing of small adult and sub-adult striped bass Morone saxatilis on their southward autumn migration

Almost three-quarters of the 46 young adult and sub-adult striped bass Morone saxatilis that were acoustically tagged in Plum Island Estuary, Massachusetts, U.S.A., in the summer of 2006 were detected in one or more southern coastal arrays during their autumn migration. On the basis of the trajectories along which these M. saxatilis moved from feeding to overwintering areas, three migratory groups emerged. After leaving Plum Island Estuary, about half of the fish were detected only in a mid-latitude array, Long Island Sound. The other half of the tagged fish were detected during autumn and winter in a more southern array, the Delaware Estuary. This latter group of fish may have used two routes. Some travelled to the Delaware Estuary through Long Island Sound while other fish may have taken a second, more direct, coastal route that did not include Long Island Sound. Consequently, a seemingly homogeneous group of fish tagged at the same time in the same non-natal feeding location exhibited a diversity of southward movement patterns that could affect population-level processes. These three groups that differed in overwintering location and migration route could be movement contingents with migratory connectivity.

Massachusetts↗
USGS1973

Critically refracted waves in a spherically symmetric radially heterogeneous Earth model

A theoretical analysis of acoustic waves refracted by a spherical boundary across which velocity and density increase abruptly and below which velocity and density may either increase or decrease continuously with depth is formulated in terms of waves generated at a harmonic point source and scattered by a radially heterogeneous spherical body. Through the application of an Earth-flattening transformation on the radial solution and the Watson transform on the sum over eigenfunctions, the solution to the spherical problem for high frequencies is expressed as an integral for the corresponding half-space problem in which the effect of boundary curvature maps into an effective positive velocity gradient with depth. The results of both analytical and numerical evaluation of this integral can be summarized as follows for body waves in the crust and upper mantle: (1) In the special case of a critical velocity gradient (a gradient equal and opposite to the effective curvature gradient), waves interacting with the boundary at the critical angle of incidence have the same form as the classical head wave for flat, homogeneous layers. (2) For gradients more negative than critical, the amplitude of waves incident at the critical angle decay more rapidly with distance than the classical head wave. (3) For gradients that are positive, null, and less negative than critical, the amplitude of waves near the critical angle decays less rapidly with distance than the classical head wave, and at sufficiently large distances, the refracted wave field can be adequately described in terms of ray-theoretical diving waves. At intermediate distances from the critical point, the spectral amplitude of the refracted wave is scalloped due to multiple diving wave interference.

Geophysical Journal of the Royal Astronomical Soci↗
USGS2005

Source process of a long-period event at Kilauea volcano, Hawaii

We analyse a long-period (LP) event observed by a dense seismic network temporarily operated at Kilauea volcano, Hawaii, in 1996. We systematically perform spectral analyses, waveform inversions and forward modeling of the LP event to quantify its source process. Spectral analyses identify two dominant spectral frequencies at 0.6 and 1.3 Hz with associated Q values in the range 10-20. Results from waveform inversions assuming six moment-tensor and three single-force components point to the resonance of a horizontal crack located at a depth of approximately 150 m near the northeastern rim of the Halemaumau pit crater. Waveform simulations based on a fluid-filled crack model suggest that the observed frequencies and Q values can be explained by a crack filled with a hydrothermal fluid in the form of either bubbly water or steam. The shallow hydrothermal crack located directly above the magma conduit may have been heated by volcanic gases leaking from the conduit. The enhanced flux of heat raised the overall pressure of the hydrothermal fluid in the crack and induced a rapid discharge of fluid from the crack, which triggered the acoustic vibrations of the resonator generating the LP waveform. The present study provides further support to the idea that LP events originate in the resonance of a crack. 2005 RAS.

Hawaii↗
USGS2007

White sturgeon (Acipenser transmontanus) passage at the Dalles Dam, Columbia River, USA

White sturgeon (Acipenser transmontanus) ???95 cm TL were monitored using acoustic and radio telemetry at a large hydroelectric dam (the Dalles Dam) on the Columbia River, during March 2004 through November 2005 to determine timing and routes of passage and to characterize general movements. Transmitters were surgically implanted into 148 fish during the study; 90 were released into the tailrace and 58 into the forebay. We documented 26 passage events by 19 tagged fish: eight upstream via fish ladders and 18 downstream, mostly through open spill gates. During the study 17 fish entered the two ladders one or more times; 11 entered only the east ladder, three entered only the north ladder, and three entered both ladders at sometime. Residence time within the ladders by individual fish was variable, ranging from about 1 min to nearly 6 months (median = 7.7 h). Only six fish successfully ascended the east ladder, one fish twice. We could not unequivocally determine which fish ladder one fish used to pass upstream. Differences in construction between the north and east fish ladders may account for the greater success of the east fish ladder in passing sturgeon upstream. Changes to operations at hydroelectric dams to benefit migrating anadromous salmonids may influence upstream or downstream passage by white sturgeon. Altering patterns and timing of spill discharge, altering fish ladder entrance attraction flows, and the use of lights, sound, and partial barriers to direct other species of fish to preferred passage routes have unknown effects on sturgeon passage. A better understanding of the consequences to the metapopulation of increasing or precluding upstream or downstream passage is needed. ?? 2007 The Authors.

Journal of Applied Ichthyology↗
USGS2011

Microhabitat use and seasonal movements of hatchery-reared and wild shortnose sturgeon in the Savannah River, South Carolina--Georgia

Radio and acoustic telemetry were used to monitor the seasonal movement of hatchery-reared and wild shortnose sturgeon (622-927 mm total length) in the Savannah River. Diploid, and sterile hatchery-reared shortnose sturgeon, and wild shortnose sturgeon showed apparent similar seasonal patterns of movement within the river. We were unable to detect any significant differences in the seasonal mean river location, minimum daily distance moved, absolute distance moved, displacement or mean territory size among treatments. Fish moved throughout the brackish and freshwater interface area of the Savannah River during the summer months. Coinciding with decreasing fall temperatures, fish of all treatment groups moved downriver into brackish areas of the upper estuary, residing in the Front, Middle, and Back Rivers, where they remained through winter. Upriver movements of some hatchery-reared and wild groups began in early February as river temperatures began to increase. Shortnose sturgeon from each group selected apparent similar thermal, salinity and water depth conditions throughout the year. Hatchery-reared fish may be useful as surrogates for wild fish in behavioural studies. Triploid or surgically-sterilized fish may be used in situ behavioural studies where genetic contamination is a concern. It may be possible to monitor habitats used by released hatchery-reared fish to locate or verify remnant populations of rare or endangered species in systems where they are thought to be extirpated.

Journal of Applied Ichthyology↗
USGS2012

Evidence of autumn spawning in Suwannee River Gulf sturgeon, Acipenser oxyrinchus desotoi (Vladykov, 1955)

Evidence of autumn spawning of Gulf sturgeon Acipenser oxyrinchus desotoi in the Suwannee River, Florida, was compiled from multiple investigations between 1986 and 2008. Gulf sturgeon are known from egg collections to spawn in the springtime months following immigration into rivers. Evidence of autumn spawning includes multiple captures of sturgeon in September through early November that were ripe (late-development ova; motile sperm) or exhibited just-spawned characteristics, telemetry of fish that made >175 river kilometer upstream excursions to the spawning grounds in September–October, and the capture of a 9.3 cm TL age-0 Gulf sturgeon on 29 November 2000 (which would have been spawned in late September 2000). Analysis of age-at-length data indicates that ca. 20% of the Suwannee River Gulf sturgeon population may be attributable to autumn spawning. However, with the very low sampling effort expended, eggs or early life stages have not yet been captured in the autumn, which would be the conclusive proof of autumn spawning. More sampling, and sampling at previously unknown sites frequented by acoustic telemetry fish, would be required to find eggs.

Florida↗
USGS2010

Growth rates of rainbow smelt in Lake Champlain: Effects of density and diet

We estimated the densities of rainbow smelt ( Osmerus mordax ) using hydroacoustics and obtained specimens for diet analysis and groundtruthed acoustics data from mid‐water trawl sampling in four areas of Lake Champlain, USA–Canada. Densities of rainbow smelt cohorts alternated during the 2‐year study; age‐0 rainbow smelt were very abundant in 2001 (up to 6 fish per m 2 ) and age‐1 and older were abundant (up to 1.2 fish per m 2 ) in 2002. Growth rates and densities varied among areas and years. We used model selection on eight area–year‐specific variables to investigate biologically plausible predictors of rainbow smelt growth rates. The best supported model of growth rates of age‐0 smelt indicated a negative relationship with age‐0 density, likely associated with intraspecific competition for zooplankton. The next best‐fit model had age‐1 density as a predictor of age‐0 growth. The best supported models ( N = 4) of growth rates of age‐1 fish indicated a positive relationship with availability of age‐0 smelt and resulting levels of cannibalism. Other plausible models were contained variants of these parameters. Cannibalistic rainbow smelt consumed younger conspecifics that were up to 53% of their length. Prediction of population dynamics for rainbow smelt requires an understanding of the relationship between density and growth as age‐0 fish outgrow their main predators (adult smelt) by autumn in years with fast growth rates, but not in years with slow growth rates.

New York, Vermont↗
USGS2005

Controls on 222Rn variations in a fractured crystalline rock aquifer evaluated using aquifer tests and geophysical logging

Concentrations of 222 Rn in ground water may vary considerably within megascopically homogeneous rocks over relatively short distances. Calculations indicate that different hydraulic apertures of water‐bearing fractures may account for variations in dissolved 222 Rn concentration measured in domestic water wells completed in fractured Pikes Peak Granite, assuming that all other factors influencing dissolved 222 Rn concentrations are constant. Concentrations of dissolved 222 Rn range from 124 to 840 kBq m ‐3 [3,360 to 22,700 picocuries per liter (pCi L ‐1 )] within a 2.5 km 2 well field. Aquifer tests show that transmissivities range from 0.072 to 160 m 2 day ‐1 within the well field. Acoustic televiewer and heat‐pulse flow meter logging of four wells reveals that, despite tens to hundreds of fractures that intersect each well, a single fracture supplies all the flow to three wells, and one fracture provides 65% of the flow to the fourth well. Aquifer tests indicate that two pairs of the four wells are hydraulically connected. Type‐curve interpretation of early‐time data from aquifer tests reveals classic half‐slope behavior on log‐log plots of drawdown versus time for two wells, suggesting linear flow to a single fracture. Drawdown versus time for the other two wells indicates radial or pseudo‐radial flow, which suggests a higher degree of fracture interconnectivity near those boreholes. Hydraulic apertures calculated using the cubic law are 0.024 and 0.038 cm for producing fractures in the first hydraulically connected well pair and 0.011 and 0.020 cm for flowing fractures in the second well pair. Assuming uniform distribution of 226 Ra along fracture walls and long residence time of water relative to 222 Rn decay, the ratio of fracture apertures should equal the inverse ratio of 222 Rn concentration in each well. Assuming 50% error in hydraulic aperture estimation and 10% analytical uncertainty in 222 Rn measurement, differences in 222 Rn concentration between wells in the hydraulically connected pairs can be attributed solely to differences in hydraulic aperture. Different hydraulic apertures, however, do not explain different 222 Rn concentrations between well pairs. Allowing for measurement error, a cubic meter of rock transfers from 1.3 to 20 times more 222 Rn to ground water in the first pair of wells than in the second pair. Nonuniform distribution of 226 Ra along fracture walls, heterogeneous emanating power in the rock‐water system, or short ground‐water residence time along the transmissive fracture network may account for the difference between well pairs.

Colorado↗