Publications

Concentrations, loads, and yields of nitrate plus nitrite, total nitrogen, and total phosphorus were assessed in the Iowa River upstream from the Coralville Reservoir in east-central Iowa. The results of this study describe baseline nutrient transport during two historical reference periods, 1980–96 and 2006–10, that can be used to evaluate the progress of the implementation of reduction

Topographic and hydrodynamic complexity in submarine canyons promotes steep gradients in food availability and geophysical parameters which affect ecological assemblages and beta diversity. While habitat heterogeneity in submarine canyons is known to support diverse and abundant megafaunal communities, due to difficulty in sampling little is known about infaunal communities adjacent to...

Unpaved roads make up at least 14 million kilometers of the worldwide road network. Although investigations of road runoff often are focused on paved roads, unpaved roads contribute large volumes of runoff to roadside aquatic habitats and introduce unique constituents to runoff, such as chemical dust suppressants. At least 200 products across five chemical categories are commercially...

Dissolved organic carbon (DOC) impacts water quality, the carbon cycle, and the ecology of aquatic systems. Understanding what controls DOC is therefore critical for improving large-scale models and best management practices for aquatic ecosystems. The two main processes of DOC transformation and removal, photochemical and microbial DOC degradation, work in tandem to modify and...

Herein we provide direct evidence for the consumption of Pomacea maculata (Giant Applesnail) eggs by ants in the genus Crematogaster. The observations were made during removal of snail egg masses at the Hudson Woods Unit of the Texas Mid-Coast National Wildlife Refuge, TX. We observed acrobat ants (Crematogaster sp.) removing snail eggs from an egg mass and carrying eggs back to their...

During migration, transient birds usually find themselves stopping in unfamiliar habitats in order to rest and refuel before resuming migratory flight. Here we document the first case, to our knowledge, of a Tennessee Warbler (Leiothlypis peregrina) entrapped in a spiderweb. The warbler's tarsus became caught in the mooring thread of a golden silk orb-weaver (Trichonephila clavipes) web...

The data summarized in this report provide a baseline characterization of the physical attributes of the riverine ecosystems in two landscapes managed by the National Park Service—Ozark National Scenic Riverways, Missouri, and Buffalo National River, Arkansas—to inform understanding and management of aquatic habitat. The study utilized a basin-scale approach and consisted of two...

Chemical-contaminant mixtures are widely reported in large stream reaches in urban/agriculture-developed watersheds, but mixture compositions and aggregate biological effects are less well understood in corresponding smaller headwaters, which comprise most of stream length, riparian connectivity, and spatial biodiversity. During 2014–2017, the U.S. Geological Survey (USGS) measured 389...

Boreal peatland forests have relatively low species diversity and thus impacts of climate change on one or more dominant species could shift ecosystem function. Despite abundant soil water availability, shallowly rooted vascular plants within peatlands may not be able to meet foliar demand for water under drought or heat events that increase vapor pressure deficits while reducing near...

We evaluated the effectiveness of a distance sampling from roads program for estimating population sizes of white-tailed deer (Odocoileus virginianus) from 2001 to 2015 in parks of the National Capital Region (NCR), National Parks Service. Distance sampling is a method for estimating the density of organisms using a distribution of distances to observed individuals. Re-analysis of survey...

Mangroves are periodically influenced in negative ways by non-freezing temperatures across their global sub-tropical range. However, physiological and morphological evidence of chilling influences to non-freezing chilling events has not been measured in field settings. In this study, we measured sap flow (Js) during such a chilling (but non-freezing) event in southern China and...

The diamondback terrapin (Malaclemys terrapin) is a small estuarine turtle distributed along the Atlantic and Gulf Coasts of the USA that is threatened by drowning in crab pots, road mortality, exploitation in the pet trade, and habitat loss. Little is known about the movement patterns and home ranges of these turtles, particularly along the U.S. Gulf of Mexico coast. Satellite tags were...