USGS Science⌕ Search

SEARCH · USGS Science

Results for “Proceedings”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,315 records · Page 73Linked to original sources
USGS2008

Microhabitat use by brook trout inhabiting small tributaries and a large river main stem: Implications for stream habitat restoration in the central Appalachians

Brook trout (Salvelinus fontinalis) habitat restoration is needed across a range of stream sizes; however, studies quantifying brook trout habitat preferences in streams of differing sizes are rare. We used radio-telemetry to quantify adult brook trout microhabitat use in a central Appalachian watershed, the upper Shavers Fork of the Cheat River in eastern West Virginia. Our objectives were to: 1) quantify non-random microhabitat use by adult brook trout in the Shavers Fork main stem (drainage area = 32 km2) and an adjacent tributary, Rocky Run (drainage area = 7 km2); and 2) construct stream-specific habitat suitability curves (HSCs) for four important microhabitat variables (depth, average current velocity, maximum current velocity within one meter, and distance to cover). Brook trout used a subset of available microhabitats in both the main stem and Rocky Run: trout tended to occupy microhabitats that were deeper, higher velocity, and closer to cover than expected by chance alone. Although specific microhabitat values differed between the main stem and tributary populations, the overall patterns in brook trout microhabitat use were consistent regardless of stream size. Habitat suitability curves were constructed based on brook trout microhabitat use and will be used to design and monitor the effectiveness of future habitat restoration efforts in the Shavers Fork watershed. Our results suggest that habitat enhancement projects that increase the availability of deep, high velocity microhabitats adjacent to cover would benefit brook trout in both small tributaries and larger river main stems.

Proceedings of the Southeastern Association of Fis↗
USGS2011

Dispersal and dam passage of sonic-tagged juvenile lake sturgeon in the upper Tennessee River

More than 90,000 state-endangered lake sturgeon (Acipenser fulvescens) have been stocked into the French Broad River, Holston River, and Fort Loudoun Lake in the upper Tennessee River system. Although incidental reports of anglers catching these fish have increased, little is known about their fate after stocking. Therefore, this study was conducted to evaluate lake sturgeon dispersal throughout the system. Seven submersible ultrasonic receivers were deployed in the upper Tennessee River system and 37 juvenile fish (mean fork length = 660 mm) were surgically implanted with ultrasonic transmitters in the fall of 2007. These fish were stocked at two sites in the headwaters of Fort Loudoun Lake. The receivers logged 1,345 detections of tagged fish and manual tracking located 32 of the 37 tagged lake sturgeon over 21 months. Ten (31%) tagged fish passed through Fort Loudoun Dam and were located downstream in the headwaters of Watts Bar Reservoir; the other tagged fish were still at large above Fort Loudoun Dam when tracking ceased in 2009. Of all fish stocked, three (9%) were last located in the French Broad River and none were located in the Holston River.

Tennessee↗
USGS2015

Reasons anglers did not respond to an internet survey and evaluation of data quality

Natural resource management agencies have traditionally used statewide mail surveys to gather information from anglers, but cost savings and faster returns occur using the internet. This study examined mail or internet fishery survey return rates and associated data by license type of South Dakota resident anglers. Junior anglers (ages 16-18; Junior Combination license) had the lowest internet and mail survey return rates (20% and 28%, respectively), followed by adult anglers (ages 19-64; Adult Fishing and Adult Combination licenses; 30% and 39%, respectively), and senior anglers (ages 65+; Senior Fishing and Senior Combination licenses; 42% and 66%, respectively). The three age groups were significantly different on three email use characteristics (shared email, frequency of use, and comfort level). The primary reason for not responding to the internet survey was not receiving or noticing the email request, and secondarily, being too busy to respond. Although having a relatively low response rate, data collected by the internet compared to follow-up mail surveys of internet non-respondents were similar.

Proceedings of the South Dakota Academy of Science↗
USGS2017

Wildlife value orientation stability among South Dakota residents: Setting the stage for a longitudinal analysis

The concept of wildlife value orientations (WVOs) has been useful for understanding the diversity of public interests in wildlife management and has been shown to be a strong predictor of public attitudes towards a wide range of wildlife management actions and policies. WVOs consist of two predominant value orientations (domination and mutualism) defined by how people view their relationship with wildlife. WVO assessment, which analyzes response patterns on a series of scaled agree/disagree statements representing these two orientations, has led to the identification of four distinct types of people: a) utilitarian (high score on domination and low score on mutualism); (b) mutualist (low score on domination and high score on mutualism); (c) pluralist (high score on both WVO scales); and (d) distanced (low score on both WVO scales). The theoretical framework of WVOs is based on evidence that changing lifestyles arising from modernization contribute to a gradual shift away from domination toward mutualism. This theory suggests a longitudinal process of change that was tested in 2004 by cross-sectional analyses in 19 western states. More recent replications of WVO assessment in South Dakota in 2012 measured relatively similar proportions of WVO types (50% and 49% utilitarian, 15% and 16% mutualist, 29% and 25% pluralist, and 6% and 10% distanced in 2004 and 2012, respectively). Also, we identified similar proportions of WVO types and recreation participation comparing two counties with the largest urban populations (Minnehaha and Pennington) to the remainder of the state. Our results illustrate opportunities for continuing longitudinal analyses of WVO with an additional focus on within state changes.

Proceedings of the South Dakota Academy of Science↗
USGS2016

A comparison of lead lengths for mini-fyke nets to sample age-0 gar species

Mini-fyke nets are often used to sample small-bodied fishes in shallow (<1 m depth) water, especially in vegetated shoreline habitats where seines are ineffective. Recent interest in gar (Lepisosteidae) ecology and conservation led us to explore the use of mini-fyke nets to capture age-0 gar and specifically how capture is affected by lead length of the fyke net. In the summers of 2012, 2013, and 2015, mini-fyke nets with two different lead lengths (4.57 m and 9.14 m) were set at random sites in backwaters and coves of the Red River arm of Lake Texoma, Oklahoma. Mean CPUE (catch-per-unit-effort; number per net night) was significantly lower for mini-fyke nets with short leads (0.52) compared to those with long leads (1.51). Additionally, Spotted Gar ( Lepisosteus oculatus ) were captured at a higher rate than the other three gar species present in Lake Texoma, although this could have been an artifact of sampling location. We found that differences in length-frequency of captured gar between gear types were nearly significant, with total length ranging from 47mm to 590mm. Mini-fyke nets with longer leads increased the efficiency of sampling for age-0 gar by increasing catch rate without affecting estimates of other population parameters and appear to be useful for this purpose.

Proceedings of the Oklahoma Academy of Science↗
USGS2017

Importance of fishing as a segmentation variable in the application of a social worlds model

Market segmentation is useful to understanding and classifying the diverse range of outdoor recreation experiences sought by different recreationists. Although many different segmentation methodologies exist, many are complex and difficult to measure accurately during in-person intercepts, such as that of creel surveys. To address that gap in the literature, we propose a single-item measure of the importance of fishing as a surrogate to often overly- or needlesslycomplex segmentation techniques. The importance of fishing item is a measure of the value anglers place on the activity or a coarse quantification of how central the activity is to the respondent’s lifestyle (scale: 0 = not important, 1 = slightly, 2 = moderately, 3 = very, and 4 = fishing is my most important recreational activity). We suggest the importance scale may be a proxy measurement for segmenting anglers using the social worlds model as a theoretical framework. Vaske (1980) suggested that commitment to recreational activities may be best understood in relation to social group participation and the social worlds model provides a rich theoretical framework for understanding social group segments. Unruh (1983) identified four types of actor involvement in social worlds: strangers, tourists, regulars, and insiders, differentiated by four characteristics (orientation, experiences, relationships, and commitment). We evaluated the importance of fishing as a segmentation variable using data collected by a mixed-mode survey of South Dakota anglers fishing in 2010. We contend that this straightforward measurement may be useful for segmenting outdoor recreation activities when more complicated segmentation schemes are not suitable. Further, this index, when coupled with the social worlds model, provides a valuable framework for understanding the segments and making management decisions.

Proceedings of the South Dakota Academy of Science↗
USGS2018

United States bat species of concern: A synthesis

In 1994 the federal government designated 24 species or subspecies of bats in the United States (U.S.) and its territories as Category 2 candidates for listing as Endangered or Threatened under the U.S. Endangered Species Act. Category 2 was eliminated in 1996, but taxa previously receiving this designation were informally considered “species of concern”. Various state and federal agencies and conservation organizations assigned bat species of concern to more formal conservation categories. Some of the original 24 taxa designated as Category 2 candidates in 1994 were later listed as Endangered, whereas others were subject to refinements in knowledge of their taxonomy and distribution. The remaining 20 species of bats have the subjects of increased research efforts over the past two decades, and are the focus of this review. Two species occur in the U.S. Territories. All of the 18 mainland species ranges include areas west of the Mississippi River (15 are found primarily in western states), and 13 occur in California (72% of the 18 mainland species). In this review, we provide a comprehensive summary of the literature pertinent to the conservation designations, systematics, distribution, habitats, relative abundance, foraging, diet, roosting ecology, population ecology, and management of each of these 20 species. The species of concern are distributed among four families of bats. The Samoan flying fox (Pteropus samoensis) belong to the old-world family Pteropodidae. The California leaf-nosed bat (Macrotus californicus), red fruit bat (Stenoderma rufum), and Mexican long-tongued bat (Choeronycteris mexicana) are members of the new-world family Phyllostomidae. Three species belong to the cosmopolitan family Molossidae: the greater bonneted bat (Eumops perotis californicus), Underwood’s bonneted bat (Eumops underwoodi), and the big free-tailed bat (Nyctinomops macrotis). Most bat species of concern are in the globally distributed family Vespertilionidae: Townsend’s big-eared bat (Corynorhinus townsendii), Rafinesque’s big-eared bat (C. rafinesquii), spotted bat (Euderma maculatum), Allen’s big-eared bat (Idionycteris phyllotis), southeastern myotis (M. austroriparius), western small-footed myotis (Myotis ciliolabrum), long-eared myotis (M. evotis), eastern small-footed myotis (M. leibii), Arizona myotis (M. occultus), fringed myotis (M. thysanodes), cave myotis (M. velifer), long-legged myotis (M. volans), and Yuma myotis (M. yumanensis). An impressive amount of knowledge has accumulated about these species since their informal designation as species of concern, but this knowledge is unevenly distributed. Comparatively little research has been conducted on the Samoan flying fox and the red fruit bat over the past decade in tropical territories, nor on the Mexican long-tongued bat and Underwood’s mastiff bat in the southwestern U.S. Within temperate regions of the U.S., habitat use of two eastern species that roost in hollow trees or caves (southeastern myotis and Rafinesque’s big-eared bat) has been the focus of much research, as have aspects of the biology of cave-roosting and tree-roosting western species, particularly where information about management of forests, caves and abandoned mines can be used to benefit bat conservation. Comparatively less information has accrued about species that roost in rock crevices and high on cliff faces. Other major gaps in information are also identified. We anticipate that this review will help guide future research and conservation efforts directed at the bat species of concern.

Proceedings of the California Academy of Sciences,↗
USGS1992

Food preferences of spring-migrating blue-winged teal in southwestern Louisiana

We studied effects of pair status, molt intensity, and year on food selection by migrating male blue-winged teal (Anas discors) in southwestern Louisiana during springs 1990 and 1991. Diets consisted primarily of animal foods; but plant material, consisting mostly of seeds, comprised as much as 44%. There was no difference in animal food consumption by paired and unpaired males; however, the proportion of animal material in the male diet was greater in 1990 than in 1991. Animal food consumption was not positively correlated with mean molt intensity. Food preferences of paired and unpaired males were similar in both years. Animal foods, especially benthos and organisms associated with vegetative substrates, were preferred to seeds and freeswimming invertebrates. We recommend that habitat management for spring-migrating blue-winged teal focus on production of invertebrates, especially long-lived forms such as dragonflies, hemipterans (except water boatmen), midges, and other dipterans.

Louisiana↗
USGS2018

Evaluation of internet surveys for conducting statewide angler surveys in South Dakota

Stakeholder information is critical for effective fisheries management. Agencies have traditionally used infrequent mail surveys to collect human dimensions data. Internet surveys provide cost savings, but are associated with caution due to data quality issues. To improve study validity, survey access can be controlled using email invitations, but because these addresses are voluntary, results may not be applicable to the entire population. Additionally, internet surveys typically have lower response rates than mail surveys, thus, a greater potential for nonresponse bias. To identify potential coverage and nonresponse biases in information typically collected by statewide angler surveys, we emailed a link to a web-based survey to all anglers who provided South Dakota Game, Fish and Parks (SDGFP) with an email address at the end of the 2011 and 2012 fishing seasons (December 31). Next, we mailed the same questionnaire to both a random sample of anglers not providing an email address and a sample of non-respondents to the internet survey. Internet survey results were similar to both mail surveys for variables SDGFP typically monitors via statewide angler surveys with the exception of slightly over representing male anglers and younger anglers; however, these slight biases can be adjusted by weighting procedures. Results from this study were used by SDGFP to design a web-based, annual statewide angler survey that would collect angler information statistically comparable to information collected by traditional statewide mail surveys.

South Dakota↗
USGS2019

Age, succesion planning & wildlife values of Upper Midwest landowners

It is well known that farmers are getting older; in the United States the average age of farmers is 58.3 years old and the rate of increase in age is accelerating. The average farmer age increased 10 years from 47.6 years old to 57.1 in a four year period (2003-2007). It is not necessarily a problem that farmers are getting older because farmers often retire later than workers in other parts of the labor force. The concern is that aging farmers are not being replaced by younger farmers since start-up costs have become insurmountable for many beginning farmers. Consequently, the age distribution of farmers has become highly skewed towards the older end of the spectrum. All the projections call for a massive transfer of land in the next decade which can have significant consequences as well as opportunities for wildlife management. For example, paid conservation programs may be especially attractive to older farmers who do not want to quit farming “cold turkey” by providing income for enrolling some land in these programs as well as reduce their work load. Our surveys of landowners in North Dakota, South Dakota and western Minnesota included questions asking landowners about their future plans for their land when they are no longer able to run their farm/ranch. About 54% of the landowners do not have any plans to change the size of their operations in the next 10 years, about 7% plan to decrease their operations and 31% plan to increase (8% undecided). These findings were strongly related to landowner age and current size of their farm/ranch. Most landowners (55%) have a strong desire to pass their farm/ranch operations on to family members and most (63%) were interested in conservation programs that would allow family members to continue with current farming/ranching operations. Most landowners’ future plans were not related to landowners’ land use and wildlife values, but for a small subset of landowners, land use and wildlife values were related to their succession plans.

Minnesota, North Dakota, South Dakota↗
USGS2005

Scanning electron microscope studies of some early Miocene diatoms from the equatorial Pacific Ocean with descriptions of two new species, Actinocyclus jouseae Barron and Actinocyclus nigriniae Barron

Scanning electron microscope (SEM) and light microscope (LM) studies are used to propose and describe two new species, Actinocyclus jouseae Barron , sp. nov. and Actinocyclus nigriniae Barron , sp. nov. from lower Miocene sediments from equatorial Pacific ODP Site 1219. Parallel SEM and LM studies reveal that Thalassiosira bukryi Barron should be transferred to Azpeitia and suggest that Actinocyclus barronii Radionova is likely to be a variety of A. radionovae Barron

Proceedings of the California Academy of Sciences ↗
USGS2021

Accelerating ecological sciences from above: Spatial contrastive learning for remote sensing

The rise of neural networks has opened the door for automatic analysis of remote sensing data. A challenge to using this machinery for computational sustainability is the necessity of massive labeled data sets, which can be cost-prohibitive for many non-profit organizations. The primary motivation for this work is one such problem; the efficient management of invasive species -- invading flora and fauna that are estimated to cause damages in the billions of dollars annually. As an ongoing collaboration with the New York Natural Heritage Program, we consider the use of unsupervised deep learning techniques for dimensionality reduction of remote sensing images, which can reduce sample complexity for downstream tasks and decreases the need for large labeled data sets. We consider spatially augmenting contrastive learning by training neural networks to correctly classify two nearby patches of a landscape as such. We demonstrate that this approach improves upon previous methods and naive classification for a large-scale data set of remote sensing images derived from invasive species observations obtained over 30 years. Additionally, we simulate deployment in the field via active learning and evaluate this method on another important challenge in computational sustainability -- landcover classification -- and again find that it outperforms previous baselines.

Proceedings of the AAAI Conference on Artificial I↗