Other Environmental Sciences Commons^™

Ecology Of An Isolated Muskrat Population During Regional Population Declines, Laken S. Ganoe, Matthew J. Lovallo, Justin D. Brown, W. David Walter

United States Geological Survey: Staff Publications

Evidence indicating a decline in Ondatra zibethicus (Muskrat) populations in the United States during the past 40 years has led to speculation regarding factors influencing Muskrat survival. In order to understand population dynamics and survival, it is important to first define the ecology of local populations. We investigated the dwelling structure use, movements, home range, and survival of radio-tagged Muskrats (n = 14) in an urban wetland complex in central Pennsylvania. We used locations collected from intensive radio-telemetry monitoring to determine number of lodging structures used, hourly movement, and size and percent area overlap of home ranges. Muskrats shared …

Quantifying Model Structural Uncertainty Using Airborne Electromagnetic Data, Burke J. Minsley, Nathan Leon Foks, Paul A. Bedrosian

United States Geological Survey: Staff Publications

The ability to quantify structural uncertainty in geological models that incorporate geophysical data is affected by two primary sources of uncertainty: geophysical parameter uncertainty and uncertainty in the relationship between geophysical parameters and geological properties of interest. Here, we introduce an open-source, trans-dimensional Bayesian Markov chain Monte Carlo (McMC) algorithm GeoBIPy—Geophysical Bayesian Inference in Python—for robust uncertainty analysis of time-domain or frequency-domain airborne electromagnetic (AEM) data. The McMC algorithm provides a robust assessment of geophysical parameter uncertainty using a trans-dimensional approach that lets the AEM data inform the level of model complexity necessary by allowing the number of model layers …

Elemental And Radionuclide Exposures And Uptakes By Small Rodents, Invertebrates, And Vegetation At Active And Post-Production Uranium Mines In The Grand Canyon Watershed, Danielle Cleveland, Jo Ellen Hinck, Julia S. Lankton

United States Geological Survey: Staff Publications

The effects of breccia pipe uranium mining in the Grand Canyon watershed (Arizona) on ecological and cultural resources are largely unknown. We characterized the exposure of biota to uranium and cooccurring ore body elements during active ore production and at a site where ore production had recently concluded. Our results indicate that biota have taken up uranium and other elements (e.g., arsenic, cadmium, copper, molybdenum, uranium) from exposure to ore and surficial contamination, like blowing dust. Results indicate the potential for prolonged exposure to elements and radionuclides upon conclusion of active ore production. Mean radium-226 in deer mice was up …

Terrestrial Ecological Risk Analysis Via Dietary Exposure At Uranium Mine Sites In The Grand Canyon Watershed (Arizona, Usa), Jo Ellen Hinck, Danielle Cleveland, Bradley E. Sample

United States Geological Survey: Staff Publications

The U.S. Department of the Interior recently included uranium (U) on a list of mineral commodities that are considered critical to economic and national security. The uses of U for commercial and residential energy production, defense applications, medical device technologies, and energy generation for space vehicles and satellites are known, but the environmental impacts of uranium extraction are not always well quantified. We conducted a screening-level ecological risk analysis based on exposure to miningrelated elements via diets and incidental soil ingestion for terrestrial biota to provide context to chemical characterization and exposures at breccia pipe U mines in northern Arizona. …

Metabarcoding Assays For The Detection Of Freshwater Mussels (Unionida) With Environmental Dna, Katy E. Klymus, Catherine A. Richter, Nathan Thompson, Jo Ellen Hinck, Jess W. Jones

United States Geological Survey: Staff Publications

Freshwater mussels of the order Unionida are a widely distributed taxon that are important in maintaining freshwater ecosystems and are also highly imperiled throughout the world. Monitoring of mussel populations with environmental DNA (eDNA) is an attractive alternative to traditional methods because it is noninvasive and requires less labor and taxonomic knowledge from field personnel. We developed eDNA metabarcoding assays specific to freshwater mussels and tested them at six sites in the Clinch River, located in the southeastern United States. Our objective was to determine the utility of eDNA metabarcoding for future monitoring of mussel populations and restoration efforts in …

The Marine Terraces Of Santa Cruz Island, California: Implications For Glacial Isostatic Adjustment Models Of Last-Interglacial Sea-Level History, Daniel R. Muhs, R. Randall Schumann, Lindsey T. Groves, Kathleen R. Simmons, Christopher R. Florian

United States Geological Survey: Staff Publications

Glacial isostatic adjustment (GIA) models hypothesize that along coastal California, last interglacial (LIG, broadly from ~130 to ~115 ka) sea level could have been as high as +11 m to +13 m, relative to present, substantially higher than the commonly estimated elevation of +6 m. Areas with low uplift rates can test whether such models are valid. Marine terraces on Santa Cruz Island have previously been reported to occur at low (<10 m) elevations, but ages of many such localities are not known. Using lidar imagery as a base, marine terraces on Santa Cruz Island were newly mapped, elevations were measured, fossils were collected for U-series dating (corals), strontium isotope compositions and amino acid geochronology (mollusks), and paleozoogeography (all taxa). Sr isotope compositions of mollusks from the highest of three marine terraces give ages of ~2.5 Ma to 1.9 Ma, along with Pliocene ages, fromshells interpreted to be reworked. U-series ages of corals fromthewestern part of the island indicate that low-elevation terraces north of the Santa Cruz Island fault correlate to the LIG. Where corals are lacking, amino acid ratios and faunal aspects support terrace correlation to the LIG high stand of sea. Elevations of most terrace localities north of the east-west trending Santa Cruz Island fault, in both thewestern and eastern parts of the island, range from5.75mto 8mabove sea level, well belowthe modeled paleo-sealevel range. Subsidence is ruled out as a mechanism for explaining the lower-than-modeled elevations, because higher-elevation terraces are present alongmuch of the Santa Cruz Island coast north of the fault, indicating longterm tectonic uplift. The low elevations of the LIG terrace fragments are, however, consistent with a low rate of uplift derived from the higher, ~2.5–1.9 Ma terrace. A number of other localities on the Pacific Coast, also dated to the LIG, have marine terrace elevations below the modeled level. GIA models may have overestimated last interglacial sea level by a substantial amount and need to be revised if used for forecasts for future sea-level rise.

Impacts Of Environmental Conditions On Fleas In Black-Tailed Prairie Dog Burrows, Julia E. Poje, Tonie Rocke, Michael D. Samuel

United States Geological Survey: Staff Publications

Sylvatic plague, caused by the bacterium Yersinia pestis and transmitted by fleas, occurs in prairie dogs of the western United States. Outbreaks can devastate prairie dog communities, often causing nearly 100% mortality. Three competent flea vectors, prairie dog specialists Oropsylla hirsuta and O. tuberculata, and generalist Pulex simulans, are found on prairie dogs and in their burrows. Fleas are affected by climate, which varies across the range of black-tailed prairie dogs (Cynomys ludovicianus), but these effects may be ameliorated somewhat due to the burrowing habits of prairie dogs. Our goal was to assess how temperature and precipitation …

Implementation Of An Occupancy-Based Monitoring Protocol For A Widespread And Cryptic Species, The New England Cottontail (Sylvilagus Transitionalis), Colin P. Shea, Mitchell J. Eaton, Darryl I. Mackenzie

United States Geological Survey: Staff Publications

Context. Designing effective long-term monitoring strategies is essential for managing wildlife populations. Implementing a cost-effective, practical monitoring program is especially challenging for widespread but locally rare species. Early successional habitat preferred by the New England cottontail (NEC) has become increasingly rare and fragmented, resulting in substantial declines from their peak distribution in the mid-1900s. The introduction of a possible competitor species, the eastern cottontail (EC),may also have played a role. Uncertainty surrounding how these factors have contributed to NEC declines has complicated management and necessitated development of an appropriate monitoring framework to understand possible drivers of distribution and dynamics.

Aims. …

Repetitive Sampling And Control Threshold Improve 16s Rrna Gene Sequencing Results From Produced Waters Associated With Hydraulically Fractured Shale, Jenna L. Shelton, Elliott P. Barnhart, Leslie Ruppert, Aaron M. Jubb, Madalyn S. Blondes, Christina A. Devera

United States Geological Survey: Staff Publications

Sequencing microbial DNA from deep subsurface environments is complicated by a number of issues ranging from contamination to non-reproducible results. Many samples obtained from these environments – which are of great interest due to the potential to stimulate microbial methane generation – contain low biomass. Therefore, samples from these environments are difficult to study as sequencing results can be easily impacted by contamination. In this case, the low amount of sample biomass may be effectively swamped by the contaminating DNA and generate misleading results. Additionally, performing field work in these environments can be difficult, as researchers generally have limited access …

Evaluating Airsoft Electric Guns For Control Of Invasive Brown Treesnakes, Adam J. Knox, Björn Lardner, Amy Yackel Adams, Robert N. Reed

United States Geological Survey: Staff Publications

Firearms are often used in lethal control of invasive vertebrates, but safety and regulatory aspects limit the circumstances under which they can be used. During August 2016 at the Brown Treesnake Project laboratory on Guam, we evaluated hobby‐grade Airsoft Electric Guns (AEGs; a lower powered, less‐hazardous, and less‐regulated alternative to firearms) for capture and control of small animals, with specific emphasis on invasive brown treesnakes (Boiga irregularis). Tests of AEGs differing in power with ammunition (plastic pellets) masses ranging from 0.20 to 0.39 g, fired at gelatin blocks from distances of 4, 8, and 12 m, showed that …

Adjusting The Lens Of Invasion Biology To Focus On The Impacts Of Climate-Driven Range Shifts, Piper D. Wallingford, Toni Lyn Morelli, Jenica M. Allen, Evelyn M. Beaury, Dana M. Blumenthal, Bethany A. Bradley, Jeffrey S. Dukes, Regan Early, Emily J. Fusco, Deborah E. Goldberg, Inés Ibáñez, Brittany B. Laginhas, Montserrat Vilà, Cascade J.B. Sorte

United States Geological Survey: Staff Publications

As Earth’s climate rapidly changes, species range shifts are considered key to species persistence. However, some range-shifting species will alter community structure and ecosystem processes. By adapting existing invasion risk assessment frameworks, we can identify characteristics shared with high-impact introductions and thus predict potential impacts. There are fundamental differences between introduced and range-shifting species, primarily shared evolutionary histories between range shifters and their new community. Nevertheless, impacts can occur via analogous mechanisms, such as wide dispersal, community disturbance and low biotic resistance. As ranges shift in response to climate change, we have an opportunity to develop plans to facilitate advantageous …

Increased Drought Severity Tracks Warming In The United States’ Largest River Basin, Justin T. Martin, Gregory T. Pederson, Connie A. Woodhouse, Edward R. Cook, Gregory J. Mccabe, Kevin J. Anchukaitis, Erika K. Wise, Patrick J. Erger, Larry Dolan, Marketa Mcguire, Subhrendu Gangopadhyay, Katherine J. Chase, Jeremy S. Litell, Stephen T. Gray, Scott St. George, Jonathan M. Friedman, David J. Sauchyn, Jeannine-Marie St-Jacques, John King

United States Geological Survey: Staff Publications

Across the Upper Missouri River Basin, the recent drought of 2000 to 2010, known as the “turn-of-the-century drought,” was likely more severe than any in the instrumental record including the Dust Bowl drought. However, until now, adequate proxy records needed to better understand this event with regard to long-term variability have been lacking. Here we examine 1,200 y of streamflow from a network of 17 new tree-ring–based reconstructions for gages across the upper Missouri basin and an independent reconstruction of warm-season regional temperature in order to place the recent drought in a long-term climate context. We find that temperature has …

David Quentin Bowen: A Memorial, John T. Andrews, David R. Bridgland, Peter U. Clark, Thomas M. Cronin, Claude Hillaire-Marcel, Darrel Maddy, Gifford H. Miller, Daniel R. Muhs, Colin V. Murray-Wallace

United States Geological Survey: Staff Publications

The Quaternary community lost a giant and a leader on October 5, 2020, when David Quentin Bowen, known to many as “DQ” and founding editor of Quaternary Science Reviews, passed away in Cardiff. Born on February 14, 1938 in Llanelli, SouthWales, he received his PhD at University College London. David’s 50 years of contributions to our science cannot be adequately summarized in a brief memorial but past, present, and future generations of Quaternary scientists will long remember his landmark achievements in publishing, his scientific contributions, and his personal and professional class in all his endeavors.

Testing Glacial Isostatic Adjustment Models Of Last-Interglacial Sea Level History In The Bahamas And Bermuda, Daniel R. Muhs, Kathleen R. Simmons, R. Randall Schumann, Eugene S. Schweig, Mark P. Rowe

United States Geological Survey: Staff Publications

Part of the spatial variation in the apparent sea-level record of the last interglacial (LIG) period is due to the diverse response of coastlines to glacial isostatic adjustment (GIA) processes, particularly where coastlines were close to the Laurentide Ice Sheet during the past two glacial periods. We tested modeled LIG paleo-sea levels on New Providence Island (NPI), Bahamas and Bermuda by investigating emergent coral patch reefs and oolitic/peloidal beach deposits. Corals with closed-system histories collected from patch reefs on NPI have ages of 128-118 ka and ooids/peloids from beach ridges have closed-system ages of 128-116 ka. Elevations of patch reefs …

Uptake, Metabolism, And Elimination Of Fungicides From Coated Wheat Seeds In Japanese Quail (Coturnix Japonica), Michael S. Gross, Thomas G. Bean, Michelle L. Hladik, Barnett A. Rattner, Kathryn M. Kuivila

United States Geological Survey: Staff Publications

Pesticides coated to the seed surface potentially pose an ecological risk to granivorous birds that consume incompletely buried or spilled seeds. To assess the toxicokinetics of seeds treated with current-use fungicides, Japanese quail ( Coturnix japonica) were orally dosed with commercially coated wheat seeds. Quail were exposed to metalaxyl, tebuconazole, and fludioxonil at either a low dose (0.0655, 0.0308, and 0.0328 mg/kg of body weight, respectively) or a high dose (0.196, 0.0925, and 0.0985 mg/kg of body weight, respectively). Fungicides were rapidly absorbed and distributed to tissues. Tebuconazole was metabolized into tert-butylhydroxy-tebuconazole. All compounds were eliminated to below detection limits …

Adjusting The Lens Of Invasion Biology To Focus On The Impacts Of Climate-Driven Range Shifts, Piper D. Wallingford, Toni Lyn Morelli, Jenica M. Allen, Evelyn M. Beaury, Dana M. Blumenthal, Bethany A. Bradley, Jeffrey S. Dukes, Regan Early, Emily J. Fusco, Deborah E. Goldberg, Inés Ibáñez, Brittany B. Laginhas, Montserrat Vilà, Cascade J.B. Sorte

United States Geological Survey: Staff Publications

As Earth’s climate rapidly changes, species range shifts are considered key to species persistence. However, some range-shifting species will alter community structure and ecosystem processes. By adapting existing invasion risk assessment frameworks, we can identify characteristics shared with high-impact introductions and thus predict potential impacts. There are fundamen- tal differences between introduced and range-shifting species, primarily shared evolutionary histories between range shifters and their new community. Nevertheless, impacts can occur via analogous mechanisms, such as wide dispersal, community disturbance and low biotic resistance. As ranges shift in response to climate change, we have an opportunity to develop plans to facilitate …

Uptake, Metabolism, And Elimination Of Fungicides From Coated Wheat Seeds In Japanese Quail (Coturnix Japonica), Michael S. Gross, Thomas G. Bean, Michelle L. Hladik, Barnett A. Rattner, Kathryn M. Kuivila

United States Geological Survey: Staff Publications

Pesticides coated to the seed surface potentially pose an ecological risk to granivorous birds that consume incompletely buried or spilled seeds. To assess the toxicokinetics of seeds treated with current-use fungicides, Japanese quail ( Coturnix japonica) were orally dosed with commercially coated wheat seeds. Quail were exposed to metalaxyl, tebuconazole, and fludioxonil at either a low dose (0.0655, 0.0308, and 0.0328 mg/kg of body weight, respectively) or a high dose (0.196, 0.0925, and 0.0985 mg/kg of body weight, respectively). Fungicides were rapidly absorbed and distributed to tissues. Tebuconazole was metabolized into tert-butylhydroxy-tebuconazole. All compounds were eliminated to below detection limits …

Estimating Abiotic Thresholds For Sagebrush Condition Class In The Western United States, Stephen Boyte, Bruce K. Wylie, Yingxin Gu, Donald J. Major

United States Geological Survey: Staff Publications

Sagebrush ecosystems of the western United States can transition from extended periods of relatively stable conditions to rapid ecological change if acute disturbances occur. Areas dominated by native sagebrush can transition from species-rich native systems to altered states where non-native annual grasses dominate, if resistance to annual grasses is low. The non-native annual grasses provide relatively little value to wildlife, livestock, and humans and function as fuel that increases fire frequency. The more land area covered by annual grasses, the higher the potential for fire, thus reducing the potential for native vegetation to reestablish, even when applying restoration treatments. Mapping …

Acoustic Space Occupancy: Combining Ecoacoustics And Lidar To Model Biodiversity Variation And Detection Bias Across Heterogeneous Landscapes, Danielle I. Rappaport, J. Andrew Royle, Douglas C. Morton

United States Geological Survey: Staff Publications

There is global interest in quantifying changing biodiversity in human-modified landscapes. Ecoacoustics may offer a promising pathway for supporting multi-taxa monitoring, but its scalability has been hampered by the sonic complexity of biodiverse ecosystems and the imperfect detectability of animal-generated sounds. The acoustic signature of a habitat, or soundscape, contains information about multiple taxa and may circumvent species identification, but robust statistical technology for characterizing community-level attributes is lacking. Here, we present the Acoustic Space Occupancy Model, a flexible hierarchical framework designed to account for detection artifacts from acoustic surveys in order to model biologically relevant variation in acoustic space …

Human-Associated Species Dominate Passerine Communities Across The United States, Helen R. Sofaer, Curtis H. Flather, Catherine S. Jarnevich, Kristin P. Davis, Liba Pejchar

United States Geological Survey: Staff Publications

Aim: Human development and agriculture can have transformative and homogenizing effects on natural systems, shifting the composition of ecological communities towards non-native and native species that tolerate or thrive under human-dominated conditions. These impacts cannot be fully captured by summarizing species presence, as they include dramatic changes to patterns of species abundance. However, how human land use patterns and species invasions intersect to shape patterns of abundance and dominance within ecological communities is poorly understood even in well-known taxa.

Location: Conterminous United States.

Time period: 2010–2012.

Major taxa studied: Passeriformes.

Methods: We analyse continental-scale monitoring data to study the proportional …

Ecosystem Processes, Land Cover, Climate, And Human Settlement Shape Dynamic Distributions For Golden Eagle Across The Western Us, J.D. Tack, Barry R. Noon, Zachary Bowen, Brad C. Fedy

United States Geological Survey: Staff Publications

Species–environment relationships for highly mobile species outside of the breeding season are often highly dynamic in response to the collective effects of everchanging climatic conditions, food resources, and anthropogenic disturbance. Capturing dynamic space-use patterns in a model-based framework is critical as model inference often drives place-based conservation planning. We applied dynamic occupancy models to broad-scale golden eagle Aquila chrysaetos survey data collected annually from 2006 to 2012 during the late summer post-fledging period in the western US. We defined survey sites as 10 km transect segments with a 1 km buffer on either transect side (n = 3540). Derived estimates …

Human-Associated Species Dominate Passerine Communities Across The United States, Helen R. Sofaer, Curtis H. Flather, Catherine S. Jarnevich, Kristin P. Davis

United States Geological Survey: Staff Publications

Aim: Human development and agriculture can have transformative and homogenizing effects on natural systems, shifting the composition of ecological communities towards non-native and native species that tolerate or thrive under human-dominated conditions. These impacts cannot be fully captured by summarizing species presence, as they include dramatic changes to patterns of species abundance. However, how human land use patterns and species invasions intersect to shape patterns of abundance and dominance within ecological communities is poorly understood even in well-known taxa.

Location: Conterminous United States.

Time period: 2010–2012.

Major taxa studied: Passeriformes.

Methods: We analyse continental-scale monitoring data to study the proportional …

Acoustic Space Occupancy: Combining Ecoacoustics And Lidar To Model Biodiversity Variation And Detection Bias Across Heterogeneous Landscapes, Danielle I. Rappaport, J. Andrew Royle, Douglas C. Morton

United States Geological Survey: Staff Publications

There is global interest in quantifying changing biodiversity in human-modified landscapes. Ecoacoustics may offer a promising pathway for supporting multi-taxa monitoring, but its scalability has been hampered by the sonic complexity of biodiverse ecosystems and the imperfect detectability of animal-generated sounds. The acoustic signature of a habitat, or soundscape, contains information about multiple taxa and may circumvent species identification, but robust statistical technology for characterizing community-level attributes is lacking. Here, we present the Acoustic Space Occupancy Model, a flexible hierarchical framework designed to account for detection artifacts from acoustic surveys in order to model biologically relevant variation in acoustic space …

Characterization Of Pallid Sturgeon (Scaphirhynchus Albus) Spawning Habitat In The Lower Missouri River, Caroline M. Elliott, Aaron J. Delonay, Kimberly Chojnacki, Robert B. Jacobson

United States Geological Survey: Staff Publications

Acipenseriformes (sturgeons and paddlefish) globally have declined throughout their range due to river fragmentation, habitat loss, overfishing, and degradation of water quality. In North America, pallid sturgeon (Scaphirhynchus albus) populations have experienced poor to no recruitment, or substantial levels of hybridization with the closely related shovelnose sturgeon (S. platorynchus). The Lower Missouri River is the only portion of the species’ range where successful reproduction and recruitment of genetically pure pallid sturgeon have been documented. This paper documents spawning habitat and behavior on the Lower Missouri River, which comprises over 1,300 km of unfragmented river habitat. The …

Late Quaternary Sea-Level History Of Saipan, Commonwealth Of The Northern Mariana Islands, Usa: A Test Of Tectonic Uplift And Glacial Isostatic Adjustment Models, Daniel R. Muhs, Eugene S. Schweig, Kathleen R. Simmons

United States Geological Survey: Staff Publications

In 1979, S. Uyeda and H. Kanamori proposed a tectonic model with two end members of a subduction-boundary continuum: the “Chilean” type (shallow dip of the subducting plate, great thrust events, compression, and uplift of the overriding plate) and a “Mariana” type (steep dip of the subducting plate, no great thrust events, tension, and no uplift). This concept has been used to explain variable rates of Quaternary uplift around the Pacific Rim, yet no uplift rates have been determined for the Mariana Islands themselves, one of the end members in this model. We studied the late Quaternary Tanapag Limestone, which …

Evidence Of Limited Recruitment Of Pallid Sturgeon In The Lower Missouri River, Kirk D. Steffensen, Kimberly Chojnacki, Jeffrey A. Kalie, Meredith L. Bartron, Edward J. Heist, Kyle R. Winders, Nathan C. Loecker, Wyatt J. Doyle, Timothy L. Welker

United States Geological Survey: Staff Publications

Pallid Sturgeon Scaphirhynchus albus are endemic to the Missouri and Mississippi river basins and are rare throughout their range. The species was listed as federally endangered with little to no evidence of natural recruitment. Since population augmentation was initiated as a recovery objective in the early 1990s, thousands of hatchery-origin Pallid Sturgeon have been stocked in the lower Missouri River (Gavins Point Dam [river kilometer 1,305.1] to the confluence of the Mississippi River [river kilometer 0.0]). Efforts to discriminate natural reproduction and recruitment of wild-origin Pallid Sturgeon from hatchery-origin fish has been hampered by tag loss in hatchery-origin sturgeon, inconsistent …

Seismic Evidence For Significant Melt Beneath The Long Valley Caldera, California, Usa, Ashton F. Flinders, David R. Shelly, Philip B. Dawson, David P. Hill, Barbara Tripoli, Yang Shen

United States Geological Survey: Staff Publications

A little more than 760 ka ago, a supervolcano on the eastern edge of California (United States) underwent one of North America’s largest Quaternary explosive eruptions. Over this ~6-day-long eruption, pyroclastic flows blanketed the surrounding ~50 km with more than 1400 km3 of the now-iconic Bishop Tuff, with ashfall reaching as far east as Nebraska. Collapse of the volcano’s magma reservoir created the restless Long Valley Caldera. Although no rhyolitic eruptions have occurred in 100 k.y., beginning in 1978, ongoing uplift suggests new magma may have intruded into the reservoir. Alternatively, the reservoir could be approaching final crystallization, with present-day …

Little Islands Recording Global Events: Late Quaternary Sea Level History And Paleozoogeography Of Santa Barbara And Anacapa Islands, Channel Islands National Park, California, Daniel R. Muhs, Lindsey T. Groves

United States Geological Survey: Staff Publications

Marine terraces are common on the Pacific Coast of North America and record interglacial high-sea stands superimposed on either stable or tectonically rising crustal blocks. Despite many years of study of these landforms in southern California, little work on terraces has been conducted on the two smallest of the California Channel Islands, Santa Barbara Island (SBI) and Anacapa Island (ANA). Presented here are new field and laboratory data on the ages, paleontology, and sea level history of marine terraces of these two islands. On both islands, the lowest marine terraces have shoreline angle elevations of ~11 m above sea level. …

Promoting Change In Common Tern (Sterna Hirundo) Nest Site Selection To Minimize Construction Related Disturbance., Peter C. Mcgowan, Jeffery D. Sullivan, Carl R. Callahan, William Schultz, Jennifer L. Wall, Diann J. Prosser

United States Geological Survey: Staff Publications

Due to the many challenges facing waterbird populations (Jia et al. 2018, Wetlands International 2018), it has become common practice to limit disturbance to breeding colonies whenever possible to maximize reproductive success. While this may require often unpopular management techniques including beach closures (Jorgensen et al. 2015, Mayo et al. 2015) and predator removal (Neuman et al. 2004, Stocking et al. 2017), such actions are sometimes necessary for the success of the colony. However, there are instances when eliminating disturbance is not possible and birds must be attracted to a new site. A common method for attracting waterbirds to a …

Management Regime And Habitat Response Influence Abundance Of Regal Fritillary (Speyeria Idalia) In Tallgrass Prairie, K. Mccullough, G. Albanese, D.A. Haukos, A.M. Ricketts, S. Stratton

United States Geological Survey: Staff Publications

The >2,570,000-ha Flint Hills ecoregion of Kansas, USA, harbors the largest remaining contiguous tract of tallgrass prairie in North America, a unique system, as the remainder of North America’s tallgrass prairie has succumbed to development and conversion. Consequently, the loss and degradation of tallgrass prairie has reduced populations of many North American prairie-obligate species including the regal fritillary (Speyeria idalia) butterfly. Population abundance and occupied range of regal fritillary have declined >99%, restricting many populations to isolated, remnant patches of tallgrass prairie. Such extensive decline has resulted in consideration of the regal fritillary for protection under the Endangered Species Act. …