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Adult and juvenile Piping Plovers (Kaiti Titherington/USFWS)
September 5, 2017

Federally-listed as threatened since 1986, the Atlantic Coast Piping Plover (Charadrius melodus) population comprises fewer than 2,000 breeding pairs, according to the most recent census data. These breeding pairs are the target of the U.S. Fish and Wildlife Service’s (USFWS) species recovery plan.

Reptile specimens
July 31, 2017

Scientists and staff of the USGS Patuxent Wildlife Research Center stationed at the Smithsonian National Museum of Natural History (NMNH) do research on the systematics and conservation of vertebrate species and curate and manage the North American collections of Amphibian, Reptile, Bird, and Mammal specimens and associated records.

Image of a new benchmark.
June 24, 2017

The southern Chesapeake Bay region is experiencing land subsidence along with rising sea levels, both of which can contribute to coastal flooding. The rates at which these two processes are occurring are not exactly known. Mapping of land elevation change requires ground-truth survey data at multiple locations that are accurate and precise. With the exception of a few CORS sites that have continuous GNSS (Global Navigation Satellite System) antennae, existing benchmarks do not have the accuracy and precision required to quantify how elevation is changing over time. A baseline network of high-accuracy benchmarks is needed to assess relative land movement across the Hampton Roads region and to calibrate satellite data that will be used to map future land elevation changes.

Lick Run concrete lined channel with Mill Mountain in the background
June 15, 2017

The U.S. Geological Survey, partnering with the City of Roanoke and Virginia Tech University, are working to monitor the water volume and quality in streams throughout the City of Roanoke. There is currently a single long-term monitoring station, Lick Run, within the city. The objective of this study is to create a model to compute suspended sediment concentrations and loads within the Lick Run Watershed from various water quality parameters. The results of this project will be used to evaluate the effectiveness of stormwater control measures taken within the watershed.

The U.S. Geological Survey is also partnering with the City of Roanoke to implement a network of eight precipitation stations that will measure real-time precipitation within the City that is publically available. This network will provide a tool to stormwater managers, utilities, and first responders to gain a better understanding of real time precipitation in an urban environment.  

Time of Concentration Estimates for Small Watersheds, WV
June 13, 2017

Many culverts and other drainage structures in rural West Virginia are located in small streams or valleys draining 100 acres or less. Design of these structures in West Virginia is generally done using discharge estimates made with widely used and well accepted methods. However, these methods require information including flow-segment length and channel geometry that are poorly characterized for very small watersheds in West Virginia. This project will allow the West Virginia Department of Transportation – Division of Highways (WVDOH) to better characterize local conditions for small, rural, predominantly forested watersheds, and verify and improve peak-flow estimates made for streams draining such watersheds.

Severn River, Annapolis, Maryland, a tributary to Chesapeake Bay, showing high sediment
May 12, 2017

The 64,000-square mile watershed that drains to the Chesapeake Bay is highly populated and has diverse land use, including forested, agricultural, and urbanized areas. Increased precipitation in the eastern United States over the last 100 years has affected stream flow and thus the loading of pollutants delivered to the bay. Such pollutants as suspended sediment and dissolved phosphorus and dissolved nitrogen enter the bay and cause environmental problems. These problems include rapid growth of algae because of the abundance of nutrients (nitrogen and phosphorus), causing huge areas of the bay to be covered in “algal blooms.” Once these algae die, they sink and decompose, using dissolved oxygen in the water to decompose. The use of dissolved oxygen for decomposition depletes the water of this essential gas, which is needed for other aquatic life. The result is “dead zones” in the bay, that is, areas of the water where there is no oxygen, technically termed anoxic. Suspended sediment delivered to the bay during high stream discharge events blocks sunlight to submerged aquatic vegetation (SAV), which need sunlight to grow. 

Shenandoah municipal and industrial discharges
May 1, 2017

A key component to assessing the contaminant exposure pathways in streams and rivers of the Chesapeake Bay is using GIS-based landscape analysis to identify sources of endocrine disrupting chemicals. Municipal and industrial wastewater treatment plant (WWTP) discharges are potentially major sources of EDCs to streams, and therefore understanding the de facto wastewater reuse (represented as fraction of stream flow consisting of WWTP effluent) at the watershed-scale is essential for predicting risk to downstream water users (human and wildlife). Another important component of landscape analysis that is important to understanding exposure pathways is the river hydrogeology, in particular areas of significant groundwater/surface water interactions, which often play a key role in habitat functions.

Over wash fan created by Hurricane Sandy in a protected area of Fire Island National Seashore.
April 27, 2017

The Challenge: The primary dune along barrier island beaches protects leeward vegetation from tidal fluctuation, salt spray and storm surge.  However, storm surges like those experienced during Hurricane Sandy can obliterate the primary dune, transporting sand inland and burying existing vegetation.  The dune rebuilds naturally as recovering vegetation traps wind-blown and waterborne sand.  The rate at which the primary dune rebuilds is determined largely by abiotic factors affecting transport of sand.  In the presence of a hyper-abundant deer population, the biotic impacts of grazing, browsing and trampling might also affect vegetation and dune recovery.

Neonicotinoid pesticides act as agonists of nicotinic acetylcholine receptors
March 21, 2017

The Challenge: Neonicotinoid pesticides act as agonists of nicotinic acetylcholine receptors (nAChRs) and are designed to be lethal to insects while theoretically posing little to no threat to vertebrates. The perceived safety of neonicotinoids has led to a sharp increase in their use in the United States and globally, since they were first introduced in 1994. The use of the neonicotinoid imidacloprid in the United States has increased 166% since 2009, from 0.75 to roughly 2 million pounds, and its use as seed treatment represents approximately 56% of total annual usage. Although neonicotinoids are designed to be selectively toxic to invertebrates, effects on other organisms are being reported. However, toxicity information on birds is particularly limited. Birds are primarily exposed to neonicotinoids orally (feeding, preening), by inhalation, or dermally depending on whether the pesticide is applied by aerial spraying or as a seed coating.

Halictus ligatus
March 20, 2017

The Challenge: Traditionally, bee identification has relied on taxonomic methods centered on descriptions of morphological differences between species. However, for many species, separate keys are required for identifying adult males and females and immature life stages. These keys are commonly unavailable. The lack of distinguishing morphological characters useful for separating closely related species is a common problem in many bee species, reducing the effectiveness and completeness of bee diversity surveys and general biological studies of bees.

Dye deposition in yolk over time
March 17, 2017

The Challenge: Endocrine active chemicals (EAC) are known to interfere with hormonally regulated physiological processes, thereby affecting signaling in the hypothalamic-pituitary-gonadal-liver (HPGL) axis and commonly resulting in reproductive dysfunction. Computational models that relate hormonal and genomic biomarkers within the HPGL axis to the reproductive cycle and ecologically relevant endpoints have been developed for fish; however, no similar model is available for birds. These models are very useful for evaluating how EAC-induced changes in physiological systems enhance or inhibit embryonic development, reproduction, and growth.