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No abstract available....

There is value in understanding the past and how it has affected the present. Science focuses on empirical findings, and we know that our prior experiences and those of our predecessors play important roles in determining how we interpret the present. We learn from accomplishments and foibles of predecessors and...

For the past 20 years or so, a commonly used explanation in the scientific literature for higher polychlorinated biphenyl (PCB) concentrations in male fish than in female fish has been that females lose a high proportion of their PCB body burden by releasing eggs at spawning time, and therefore the...

Muskellunge anglers desire to catch large fish, and release rates by recreational anglers often approach 100% (Isermann et al. 2011). Muskellunge are also a culturally significant fish for Chippewa tribes and support a subsistence spearing fishery in Wisconsin’s Ceded Territory (Erickson 2007). Although Muskellunge populations within the state’s Ceded Territory...

No abstract available....

The familiar domestic cat is not native to southern California and is considered an invasive spe-cies by biologists and conservation organizations. When owners abandon their cats, wild or feral populations may arise, as they have in San Diego County. Cats’ pelage color, tail length, and hair thickness vary widely, given...

Many biologists use digital images for estimating ages of fish, but the use of images could lead to differences in age estimates and precision because image capture can produce changes in light and clarity compared to directly viewing structures through a microscope. We used sectioned sagittal otoliths from 132 Largemouth...

Ecology has a rich history of studying ecosystem dynamics across time and space that has been motivated by both practical management needs and the need to develop basic ideas about pattern and process in nature. In situations in which both spatial and temporal observations are available, similarities in temporal behavior...

Although numerous studies have assessed retention and survival of passive integrated transponder (PIT) tags, data are scattered and information gaps remain for many diminutive fishes. Our study objectives were to 1) systematically review PIT tag studies and summarize retention, growth, and survival data for warmwater fishes; and 2) conduct a...

The National Park Service, Natural Resource Stewardship and Science office in Fort Collins, Colorado, publishes a range of reports that address natural resource topics. These reports are of interest and applicability to a broad audience in the National Park Service and others in natural resource management, including scientists, conservation and...

Widespread deployment of carbon capture and storage (CCS) is likely necessary to be able to satisfy baseload electricity demand, to maintain diversity in the energy mix, and to achieve climate and other objectives at the lowest cost. If all of the carbon dioxide (CO2) emissions from stationary sources (such as...

Determining the chemical and mineralogical variability within fine-grained mudrocks poses analytical challenges but is potentially useful for documenting subtle stratigraphic differences in physicochemical environments that may influence petroleum reservoir properties and behavior. In this study, we investigate the utility of combining principal component analysis (PCA) of X-ray diffraction (XRD) data...

BACKGROUNDMigratory waterfowl have often been implicated in the movement of troublesome agronomic and wetland weed species. However, minimal research has been conducted to investigate the dispersal of agronomically important weed species by waterfowl. The two objectives for this project were to determine what weed species are being...

A thermal tolerance study mimicking different stream environments could improve our ecological understanding of how increasing water temperatures affect stream ectotherms and improve our ability to predict organism responses based on river classification schemes. Our objective was to compare the thermal tolerances of stream fishes of different habitat guilds among...

Weathered samples from naturally exposed outcrops of troctolite associated with a magmatic Ni-Cu sulphide deposit were characterized by synchrotron-based micro-X-ray fluorescence mapping (µ-XRF) and X-ray absorption spectroscopy (XAS), as well as by lab-based X-ray diffraction, electron microscopy, Raman spectroscopy and wet chemical methods. Metal mobility in weathered samples was assessed using a sequential leach...

A major challenge of wildlife telemetry is choosing an attachment technique that maximizes transmitter retention while minimizing negative side effects. For waterbirds, attachment of transmitters with subcutaneous anchors has been an effective and well-established technique, having been used on >40 species. This method was recently modified to include a second...

Freshwater ecosystems provide many ecosystem services; however, they are often degraded as a result of human activity. To address ecosystem degradation in the Laurentian Great Lakes, Canada and the United States of America established the Great Lakes Water Quality Agreement (GLWQA). In 1987, 43 highly polluted and impacted areas were...

Sharp‐shinned Hawks (Accipiter striatus) are forest raptors that are widely distributed in the Americas. A subspecies endemic to Puerto Rico (A. s. venator) is listed as endangered and restricted to mature and old secondary montane forests and shade coffee plantations. However, recent information about the population status and distribution of Puerto Rican...

The evolutionary trajectory of populations through time is influenced by the interplay of forces (biological, evolutionary, and anthropogenic) acting on the standing genetic variation. We used microsatellite and mitochondrial loci to examine the influence of population declines, of varying severity, on genetic diversity within two Hawaiian endemic waterbirds, the Hawaiian...

Relocation studies of animal movement have focused on directed versus area restricted movement, which rely on correlations between step-length and turn angles, along with a degree of stationarity through time to define behavioral states. Although these approaches may work well for grazing foraging strategies in a patchy landscape, species...

Lava extrusion at erupting volcanoes causes rapid changes in topography and morphology on the order of tens or even hundreds of meters. Satellite radar provides a method for measuring changes in topographic height over a given time period to an accuracy of meters, either by measuring the width of radar...

No abstract available....

Understanding how anthropogenic impacts on the landscape affect wildlife requires a knowledge of community assemblages. Species surveys are the first step in assessing community structure, and recent molecular applications such as metabarcoding and environmental DNA analyses have been proposed as an additional and complementary wildlife survey method. Here, we test...

Despite nearly a century of exploitation and scientific study, predicting growth and mortality rates of the eastern oyster (Crassostrea virginica) as a means to inform local harvest and management activities remains difficult. Ensuring that models reflect local population responses to varying salinity and temperature combinations requires locally appropriate models. Using...

Habitat use can be complex, as tradeoffs among physiology, resource abundance, and predator avoidance affect the suitability of different environments for different species. Green sturgeon (Acipenser medirostris), an imperiled species along the west coast of North America, undertake extensive coastal migrations and occupy estuaries during the summer and...