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Eastern redcedar (Juniperus virginiana) is a fire-intolerant tree species that has encroached into grassland ecosystems throughout central and eastern North America. Many land managers are interested in removing eastern redcedar to restore native grasslands. We surveyed small mammals using mark-recapture methods in eastern redcedar forest, warm-season grassland, and oldfield habitats...

No abstract available ...

Global climate change is altering freshwater ecosystems and affecting fish populations and communities. Underpinning changes in fish distribution and assemblage-level responses to climate change are individual-level physiological constraints. In this review, we synthesize the mechanistic effects of climate change on neuroendocrine, cardiorespiratory, immune, osmoregulatory, and reproductive systems of freshwater and...

Coastal ecosystems are dynamic and productive areas that are vulnerable to effects of global climate change. Despite their potentially limited spatial extent, submerged aquatic vegetation (SAV) beds function in coastal ecosystems as foundation species, and perform important ecological services. However, limited understanding of the factors controlling SAV distribution and abundance...

The Waihi district in the Hauraki Goldfield of New Zealand contains adularia-sericite epithermal gold-silver veins that have produced more than 7.7 Moz gold. The outermost veins of the district (Martha, Favona, Moonlight, and Cowshed) contain abundant colloform, cherty, and black quartz fill textures, with minor crustiform and massive quartz. The...

What skills and knowledge will a new graduate seeking employment need to work with introduced fishes? Clearly, success in introduced species management—similar to other disciplines in fisheries—requires a mixture of scientific and communication skills. However, specific abilities especially important to a biologist who manages introduced fishes should be highlighted. Unlike...

Burbot Lota lota is the sole freshwater representative of the cod-like fishes and supports subsistence, commercial, and recreational fisheries worldwide above approximately 40° N. It is a difficult species to manage effectively due to its preference for deep-water habitats and spawning activity under the ice in winter. Like other gadiform...

Closed-circuit rebreathers have been used for underwater biological research since the late 1960s, but have only started to gain broader application within scientific diving organizations within the past two decades. Rebreathers offer certain specific advantages for such research, especially for research involving behavior and surveys that depend on unobtrusive observers...

In February 2016, the Great Lakes Executive Committee, which oversees the implementation of the Great Lakes Water Quality Agreement (GLWQA) between the U.S. and Canada, approved phosphorus loading targets for Lake Erie to reduce the size of harmful algal blooms (HABs), reduce the presence of the low oxygen zone in...

Soils on many of the outwash plains in southwestern Michigan have loamy upper profiles, despite being underlain by sand-textured outwash. The origin of this upper, loamy material has long been unknown. The purpose of this study is to analyze the spatio-textural characteristics of these loamy-textured sediments to ascertain their origin(s)....

Most studies of cross-ecosystem resource subsidies have demonstrated positive effects on recipient consumer populations, often with very large effect sizes. However, it is important to move beyond these initial addition–exclusion experiments to consider the quantitative consequences for populations across gradients in the rates and quality of resource inputs. In our...

Submerged aquatic vegetation (SAV) beds are shallow coastal habitats that are increasingly exposed to the effects of sea-level rise (SLR). In the northern Gulf of Mexico (nGoM), an area especially vulnerable to SLR, the abundance and distribution of SAV food resources (seeds, rhizomes, and tissue) can influence the carrying...

Continental-domain assessments of climate change impacts on water resources typically rely on statistically downscaled climate model outputs to force hydrologic models at a finer spatial resolution. This study examines the effects of four statistical downscaling methods [bias-corrected constructed analog (BCCA), bias-corrected spatial disaggregation applied at daily (BCSDd) and monthly scales...

Acoustic surveys were conducted in late summer/early fall during the years 1992-1996 and 2001-2015 to estimate pelagic prey fish biomass in Lake Michigan. Midwater trawling during the surveys as well as target strength provided a measure of species and size composition of the fish community for use in scaling acoustic...

U.S. Geological Survey scientists developed a dataset of 2006 and 2011 land-use and land-cover (LULC) information for selected 100-km2 sample blocks within 29 U.S. Environmental Protection Agency (EPA) Level III ecoregions across the conterminous United States. The data can be used with the previously published Land Cover Trends Dataset: 1973...

Recent studies have presented evidence that early to mid‐twentieth‐century earthquakes in Oklahoma and Texas were likely induced by fossil fuel production and/or injection of wastewater (Hough and Page, 2015; Frohlich et al., 2016). Considering seismicity from 1935 onward, Hauksson et al. (2015) concluded that there is no evidence for significant induced activity...

No abstract available....

The Coastal Expert Workshop brought together a diverse group of coastal experts with the common goal of developing a biodiversity monitoring program for coastal ecosystems across the circumpolar Arctic. Meeting participants, including northern residents, industry and Non-Governmental Organization (NGO) representatives, scientists, and government regulators from across the circumpolar Arctic, gathered...

The general physiological response of fish to threatening situations, as with all vertebrates, is referred to as stress. A stress response is initiated almost immediately following the perception of a stressor. Mildly stressful situations can have beneficial or positive effects (eustress), while higher severities induce <a...

Predictions of coastal evolution driven by episodic and persistent processes associated with storms and relative sea-level rise (SLR) are required to test our understanding, evaluate our predictive capability, and to provide guidance for coastal management decisions. Previous work demonstrated that the spatial variability of long-term shoreline change can be predicted...

Accurate age and growth information is essential for a complete knowledge of life history, growth rates, age at sexual maturity, and average life span in fishes. Alligator gar are becoming increasingly managed throughout their range and because this species spawns in backwater flooded areas, their offspring are prone to stranding...

Robust estimates of precipitation in space and time are important for efficient natural resource management and for mitigating natural hazards. This is particularly true in regions with developing infrastructure and regions that are frequently exposed to extreme events. Gauge observations of rainfall are sparse but capture the precipitation process with...

We examined trophic dynamics of a stream food web where invasive Orconectes neglectus appear to be displacing native O. eupunctus in the Spring River drainage of the Ozark Highlands, Missouri and Arkansas, USA. We collected crayfish species and possible food sources seasonally from a site of sympatry on the South Fork Spring River. We...

Many species of conservation concern are habitat limited and often a major focus of management for these species is habitat acquisition and/or restoration. Deciding the location of habitat restoration or acquisition to best benefit a protected species can be a complicated subject with competing management objectives, ecological uncertainties and stochasticity....

Noncontact methods for measuring water-surface elevation and velocity in laboratory flumes and rivers are presented with examples. Water-surface elevations are measured using an array of acoustic transducers in the laboratory and using laser scanning in field situations. Water-surface velocities are based on using particle image velocimetry or other machine vision...