mid-Atlantic Coast Research Articles

Modeling 1,3-D Concentrations in Ambient Air in High Use Airsheds of the United States

Soil fumigants, such as 1,3-dichloropropene (1,3-D), are used on a variety of different crops in high use areas in the United States, including the Pacific Northwest, the mid-Atlantic coast, and the Southeast coastal plains. Contaminant concentrations in air are often required for environmental exposure and human risk assessment. The SOil Fumigant Exposure Assessment (SOFEA) model, originally developed to explore volatile pesticide exposure and bystander risk, has recently been upgraded using AERMOD, the US Environmental Protection Agency’s (EPA) recommended regulatory air dispersion model to predict short-, medium-, and long-term pesticide concentrations in air resulting from representative agronomic practices in large airsheds. Modeling air concentrations has several advantages over monitoring such as the ability to predict concentrations at multiple locations and airsheds at a much greater temporal frequency than could be practically accomplished through monitoring alone. The agricultural modeling tool presented herein was parameterized using 1,3-D application data (mass, date, and depth applied, location, etc) obtained from growers in each study area, and local weather data and hourly concentrations of 1,3-D in ambient air were simulated for large airsheds. The human equivalent concentrations (HECs) for acute, short-term, sub-chronic, and chronic exposure of 1,3-D were not exceeded in any of the study areas investigated. These simulated 1,3-D concentrations are used to assess human exposure and risk, which considers human-life-stage-specific exposure factors, including residential mobility, time-activity patterns, and age-specific inhalation rates and body weights.

Reassessment of Large-Scale Reversals in Shoreline Trends along the U.S. Mid-Atlantic Coast

Reassessment of Large-Scale Reversals in Shoreline Trends along the U.S. Mid-Atlantic Coast

Blood biochemistry and haematology of migrating loggerhead turtles (Caretta caretta) in the Northwest Atlantic: reference intervals and intra-population comparisons

We documented blood biochemistry and haematology of healthy loggerhead turtles (Caretta caretta) in the Northwest (NW) Atlantic in order to establish clinical reference intervals (RIs) for this threatened population. Blood samples were analysed from migratory loggerheads captured off the Mid-Atlantic coast of the USA in 2011, 2012, 2013 and 2016 as part of a long-term research program. Blood variables were determined using a point-of-care analyser, and a veterinary diagnostic laboratory service. We calculated 95% RIs with associated 90% confidence intervals (CIs) for each blood variable. We compared results obtained from our study of migratory loggerheads with published data for similarly sized loggerheads resident at a seasonal temperate latitude foraging area. Significant differences in several blood variables between migratory and resident turtles provided insight on energetic and health status during different behavioural states. Temperature was significantly correlated with several blood variables: lactate, pCO2, sodium, haemoglobin and lactate dehydrogenase. Our assessment of blood chemistry in healthy loggerhead turtles in the NW Atlantic provides a baseline for clinical comparisons with turtles impacted by anthropogenic and environmental threats, and highlights the importance of identifying unique aspects of biochemical and haematological profiles for sea turtles at the intra-population level.

Palaeocene–Eocene Thermal Maximum prolonged by fossil carbon oxidation

A hallmark of the rapid and massive release of carbon during the Palaeocene–Eocene Thermal Maximum is the global negative carbon isotope excursion. The delayed recovery of the carbon isotope excursion, however, indicates that CO2 inputs continued well after the initial rapid onset, although there is no consensus about the source of this secondary carbon. Here we suggest this secondary input might have derived partly from the oxidation of remobilized sedimentary fossil carbon. We measured the biomarker indicators of thermal maturation in shelf records from the US Mid-Atlantic coast, constructed biomarker mixing models to constrain the amount of fossil carbon in US Mid-Atlantic and Tanzania coastal records, estimated the fossil carbon accumulation rate in coastal sediments and determined the range of global CO2 release from fossil carbon reservoirs. This work provides evidence for an order of magnitude increase in fossil carbon delivery to the oceans that began ~10–20 kyr after the event onset and demonstrates that the oxidation of remobilized fossil carbon released between 102 and 104 PgC as CO2 during the body of the Palaeocene–Eocene Thermal Maximum. The estimated mass is sufficient to have sustained the elevated atmospheric CO2 levels required by the prolonged global carbon isotope excursion. Even after considering uncertainties in the sedimentation rates, these results indicate that the enhanced erosion, mobilization and oxidation of ancient sedimentary carbon contributed to the delayed recovery of the climate system for many thousands of years. Delivery of fossil carbon to the oceans strongly increased about 15 kyr after the onset of the Palaeocene–Eocene Thermal Maximum as a result of oxidation of sedimentary carbon, suggests an analysis of geochemical measurements with a biomarker mixing model.

Corrigendum

Corrigendum

On the Impact of Unmanned Aerial System Observations on Numerical Weather Prediction in the Coastal Zone

Abstract The Trident Warrior observational field campaign conducted off the U.S. mid-Atlantic coast in July 2013 included the deployment of an unmanned aerial system (UAS) with several payloads on board for atmospheric and oceanic observation. These UAS observations, spanning seven flights over 5 days in the lowest 1550 m above mean sea level, were assimilated into a three-dimensional variational data assimilation (DA) system [the Naval Research Laboratory Atmospheric Variational Data Assimilation System (NAVDAS)] used to generate analyses for a numerical weather prediction model [the Coupled Ocean–Atmosphere Mesoscale Prediction System (COAMPS)] with a coupled ocean model [the Naval Research Laboratory Navy Coastal Ocean Model (NCOM)]. The impact of the assimilated UAS observations on short-term atmospheric prediction performance is evaluated and quantified. Observations collected from 50 radiosonde launches during the campaign adjacent to the UAS flight paths serve as model forecast verification. Experiments reveal a substantial reduction of model bias in forecast temperature and moisture profiles consistently throughout the campaign period due to the assimilation of UAS observations. The model error reduction is most substantial in the vicinity of the inversion at the top of the model-estimated boundary layer. Investigations reveal a consistent improvement to prediction of the vertical position, strength, and depth of the boundary layer inversion. The relative impact of UAS observations is explored further with experiments of systematic denial of data streams from the NAVDAS DA system and removal of individual measurement sources on the UAS platform.

Modeling the electrical grid impact of wind ramp-up forecasting error offshore in the Mid-Atlantic region

The large wind resource and population centers along the Mid-Atlantic Coast of the United States make it an attractive region to develop offshore wind power. Understanding and accurately predicting the meteorology offshore is fundamental to efficient integration of these future wind farms into an electrical grid. Particular interest is focused on anticipating and reducing errors associated with wind ramps, which are characterized by rapid, sustained changes in wind speed over a period of hours. Using meteorological observations from a coastal buoy, we characterize 428 wind ramp-ups between 2005 and 2012 in terms of frequency, duration and magnitude, time and date of occurrence, and large-scale synoptics. From this group, we select 24 case studies that represent typical and extreme ramp-ups at this location and then model the impact that the forecasting error of these ramp-ups could have on the electrical grid. The case studies are modeled with the Weather Research and Forecasting (WRF) model and compared with nearby buoy observations to assess forecast errors in ramp-up timing, shape, and magnitude. WRF frequently simulated ramp-ups too early, relative to observations, and often predicted the pre-ramp-up wind speed to be too high or the post-ramp-up wind speed to be too low. In the case of August 14, 2007, all three forecast errors occurred. The simulated impact on the grid is calculated by comparing the errors in forecast power with concurrent electrical load data in PJM's Mid-Atlantic Area Council-East (PJM-E) region. The largest impacts on the electrical grid were found to occur in the winter or at night in the summer. This framework allows for the identification of events that would potentially cause problems for the electrical grid in the PJM-E region.

Top-Down Impacts of Sea Nettles (Chrysaora quinquecirrha) on Pelagic Community Structure in Barnegat Bay, New Jersey, U.S.A.

ABSTRACT Bologna, P.A.X.; Gaynor, J.J.; Barry C.L., and Restaino, D.J., 2017. Top-down impacts of sea nettles (Chrysaora quinquecirrha) on pelagic community structure in Barnegat Bay, New Jersey, U.S.A.. In: Buchanan, G.A.; Belton, T.J., and Paudel, B. (eds.), A Comprehensive Assessment of Barnegat Bay–Little Egg Harbor, New Jersey. Coastal communities are substantially affected by human activities and create environments conducive to opportunistic species and structural changes in food webs. The Mid-Atlantic coast of the United States is highly urbanized with significant landscape modification and elevated pollutant loads. The appearance and development of resident populations of the Atlantic sea nettle (Chrysaora quinquecirrha) in Barnegat Bay, New Jersey demonstrates a successful establishment to this estuary. This research indicates that two species of gelatinous zooplankton (Mnemiopsis leidyi, C. quinquecirrha) play important structuring roles in the pelagic community. Specifically, M. leidyi exerts ...

Sea Level Rise Induced Arsenic Release from Historically Contaminated Coastal Soils.

Climate change-induced perturbations in the hydrologic regime are expected to impact biogeochemical processes, including contaminant mobility and cycling. Elevated levels of geogenic and anthropogenic arsenic are found along many coasts around the world, most notably in south and southeast Asia but also in the United States, particularly along the Mid-Atlantic coast. The mechanism by and the extent to which arsenic may be released in contaminated coastal soils due to sea level rise are unknown. Here we show a series of data from a coastal arsenic-contaminated soil exposed to sea and river waters in biogeochemical microcosm reactors across field-validated redox conditions. We find that reducing conditions lead to arsenic release from historically contaminated coastal soils through reductive dissolution of arsenic-bearing mineral oxides in both sea and river water inundations, with less arsenic release from seawater scenarios than river water due to inhibition of oxide dissolution. For the first time, we systematically display gradation of solid phase soil-arsenic speciation across defined redox windows from reducing to oxidizing conditions in natural waters by combining biogeochemical microcosm experiments and X-ray absorption spectroscopy. Our results demonstrate the threat of sea level rise stands to impact arsenic release from contaminated coastal soils by changing redox conditions.

Atmospheric drivers of sea-level fluctuations and nuisance floods along the mid-Atlantic coast of the USA

As sea levels have risen and continue to rise, the risk of coastal flooding has increased in turn. While many studies have examined specific extreme flooding events, far fewer have explored the systematic associations between weather events and smaller, nuisance flood events. In this research, we take a synoptic climatological approach to assess this connection. We utilize self-organizing maps (SOMs) to separately cluster two atmospheric fields, sea-level pressure and 700-hPa geopotential height. We then utilize the output from these classifications to assess the impact of atmospheric conditions on the short-term fluctuations of sea level for the period 1979–2012, as well as the likelihood of nuisance flood occurrence, at five tidal gauges from Cape May, NJ, to Charleston, SC, along the mid-Atlantic coast of the USA. Results show the impacts of both the inverted barometer effect as well as surface wind forcing. Beyond this, the SOM nodes show a clear spatial continuum of associations between circulation and anomalous sea level, including some significant sea-level anomalies associated with relatively ambiguous pressure patterns. Moreover, the transitions from 1 day to the next are also analyzed, with results showing that rapidly deepening cyclones, or persistent onshore flow, can be associated with the greatest likelihood of nuisance floods. Results are generally weaker with 700-hPa height than sea-level pressure; however, in some cases, it is clear that the mid-tropospheric circulation can modulate the connection between sea-level anomalies and surface circulation.

Depletion and response of deep groundwater to climate-induced pumping variability

Groundwater constitutes a critical component of our water resources. Widespread groundwater level declines have occurred in the USA over recent decades, including in regions not typically considered water stressed, such as areas of the Northwest and mid-Atlantic Coast. This loss of water storage reflects extraction rates that exceed natural recharge and capture. Here, we explore recent changes in the groundwater levels of deep aquifers from wells across the USA, and their relation to indices of interannual to decadal climate variability and to annual precipitation. We show that groundwater level changes correspond to selected global climate variations. Although climate-induced variations of deep aquifer natural recharge are expected to have multi-year time lags, we find that deep groundwater levels respond to climate over timescales of less than one year. In irrigated areas, the annual response to local precipitation in the deepest wells may reflect climate-induced pumping variability. An understanding of how the human response to drought through pumping leads to deep groundwater changes is critical to manage the impacts of interannual to decadal and longer climate variability on the nation’s water resources. Drought affects deep groundwater through changes in natural recharge with a multi-year time lag. Rapid changes in US groundwater storage in response to climate variability reflect the human response to drought through groundwater pumping.

Troubled Waters: Liquid Memory in the Wake of Disaster

Troubled WatersLiquid Memory in the Wake of Disaster Lauren Ravalico Artists who undertake the commemoration of a disaster are faced with a dizzying array of aesthetic choices that affect how a calamitous tragedy will be tacked to the fabric of collective memory. This essay considers the strikingly similar implications of compositional and formal choices in two visual representations of disaster which, at first glance, bear no resemblance: Théodore Géricault's 1819 tableau, The Raft of the Medusa [Le Radeau de la Méduse], and Michael Arad's Reflecting Absence, a memorial to the terrorist attacks on the World Trade Center at the National September 11 Memorial and Museum in Lower Manhattan. Géricault's Romantic painting (Figure 1) depicts a group of survivors of the shipwrecked Medusa, the frigate in a small fleet of warships that sailed from Rochefort, a port on France's mid-Atlantic coast, on June 17, 1816, and which ran aground on July 2 after striking a reef by a bank of shoals near the coast of Mauritania. The primary mission of the expedition was to reclaim from British occupation several territorial outposts in Senegal that French colonizers had originally established and which were returned to France as part of the 1815 treaty that restored monarchy in France. Among the nearly 400 passengers and crew on this voyage to the port city of Saint-Louis in Senegal were the French-appointed governor of the territories, Colonel Julien Schmaltz, the principal employees of the colony, several cartographers who were to map the Cape Verde peninsula for a future colonial settlement, as well as a large group of military personnel (including "an unknown number of blacks") to be stationed at the colony outposts and to form an army (Alhadeff 17).1 The Medusa's captain, Hugues Duroy de Chaumareys, chose a route too close to shore and thus separated from the expedition's other ships, the Loire, the Echo, and the Argus. Two days after running aground, Chaumareys abandoned ship along with most of the ship's officers, Colonel Schmaltz, and their families to clamor onto the Medusa's six dilapidated lifeboats. Because the lifeboats were insufficient to carry all of the shipwrecked passengers, it was decided to tow the remaining survivors on a hastily constructed raft (68 feet by 20 feet) made from the Medusa's masts and beams (Eitner 159).2 After setting sail, however, an officer aboard territorial governor Schmaltz's lifeboat used a hatchet to cut the rope that was towing the unwieldy raft. The remaining [End Page 60] lifeboats did not come to the raft's rescue and sailed on toward Senegal.3 Approximately 150 souls were left adrift upon a rickety floating platform with only a meager supply of wine and water. The paltry foodstuffs and coin-sized compass they originally brought onboard were lost at sea within the first day (Corréard and Savigny 101–102). For the next 13 days, horrors of every kind beset the raft, which was initially so overloaded that its passengers, packed together like sardines, sat in waist-high water (87). Violent winds and stormy weather tossed many survivors overboard; others were smothered or crushed in the thrashing about. In a drunken delirium, some of the soldiers initiated a series of violent mutiny attempts that wounded and killed more than half of the raft's passengers. The remaining survivors turned first to cannibalism and then to something in between murder and euthanasia of the critically wounded in order to attempt survival (140–41).4 When the Argus finally spotted the raft after two weeks at sea, 15 of the 150 passengers were still alive, and five of them soon died at a hospital in Saint-Louis, Senegal. Click for larger view View full resolution Figure 1. Théodore Géricault, The Raft of the Medusa, 1819. Copyright released September 28, 2016 for publication in The Comparatist. In its aftermath, the Medusa shipwreck became a political cause célèbre (Huet 155). The Medusa's captain, Chaumareys, was a Legitimist and formerly celebrated sailor in the King's Navy who hadn't helmed a ship in 25 years until the French Restoration of 1815...

Hydrogeomorphic influences on salt marsh sediment accumulation and accretion in two estuaries of the U.S. Mid-Atlantic coast

Salt marshes in two contrasting estuaries of the U.S. Mid-Atlantic coast, Barnegat Bay and Delaware Bay, were investigated to identify relationships between rates of sedimentation and marsh estuarine geomorphic setting. Barnegat Bay is a microtidal lagoon estuary with back-barrier and mainland coastal marshes, whereas Delaware Bay is a micro-mesotidal coastal plain estuary with sediment-rich estuarine marshes. Salt marshes of both estuaries are dominated by Spartina alterniflora. An analysis was performed to characterize marsh hypsometry and tidal flooding characteristics, and a coring study was conducted to measure rates of mineral sediment accumulation, organic matter accumulation, and vertical accretion using 137Cs and 210Pb chronology at nine sites in both estuaries. Mineral sediment and organic matter accumulation rates were significantly higher in Delaware Bay marshes (sediment mean and 1σ: 2.57±2.03kgm−2year−1; organic: 0.65±0.26kgm−2year−1) than in Barnegat Bay (sediment: 0.31±0.27kgm−2year−1; organic: 0.29±0.08kgm−2year−1), as were rates of accretion (Delaware Bay: 0.79±0.06cmyear−1; Barnegat Bay: 0.28±0.06cmyear−1). Regression analysis indicated that marsh accretion rates were positively correlated with rates of sediment and organic accumulation, but the upper limit of accretion was governed by sediment accumulation. Tidal flooding frequency and duration did not correlate with marsh accumulation or accretion rates in either estuary, suggesting that hydroperiod is subordinate to sediment availability in governing rates on 50–100year time scales. If true, natural and (or) human influences on suspended-sediment production and transport in these estuaries has potential to impact marsh accretionary status and stability, independent of sea-level rise.

Captains' response to a declining stock as anticipated in the surfclam (Spisula solidissima) fishery on the U.S. Mid-Atlantic coast by model evaluation

Mid-Atlantic Bight (MAB) warming accompanied by a decline in recruitment has slowly reduced surfclam abundance. Simulations examined fishery dynamics during an extended period of low recruitment followed by stock recovery after a high-recruitment event. The model assigned performance characteristics to each vessel and gave captains defined behavioral proclivities including a tendency to search, to communicate with other captains, to use survey data, and to integrate variable lengths of past-history performance in targeting fishing trips. During the simulated excursion in abundance, LPUE (landings per unit effort) declined as lower abundance required an extended time at sea to catch a full load. Captains expanded their geographic range of interest steaming farther from port in an effort to maintain their performance. Net revenue declined. Use of survey data significantly improved performance. About equal in positive effect was moderate searching. Other behaviors incurred penalties. Communication failed to improve performance because both poor and good information was transferred. Reliance on a long period of catch history failed to improve performance because information was out of date during a time of rapidly changing conditions. In these simulations, no captains' behaviors prevented a collapse in vessel economics at low abundance, but certain behaviors limited the degree and duration of economic dislocation.

Expected ozone benefits of reducing nitrogen oxide (NOx) emissions from coal-fired electricity generating units in the eastern United States

ABSTRACTOn hot summer days in the eastern United States, electricity demand rises, mainly because of increased use of air conditioning. Power plants must provide this additional energy, emitting additional pollutants when meteorological conditions are primed for poor air quality. To evaluate the impact of summertime NOx emissions from coal-fired electricity generating units (EGUs) on surface ozone formation, we performed a series of sensitivity modeling forecast scenarios utilizing EPA 2018 version 6.0 emissions (2011 base year) and CMAQ v5.0.2. Coal-fired EGU NOx emissions were adjusted to match the lowest NOx rates observed during the ozone seasons (April 1–October 31) of 2005–2012 (Scenario A), where ozone decreased by 3–4 ppb in affected areas. When compared to the highest emissions rates during the same time period (Scenario B), ozone increased ∼4–7 ppb. NOx emission rates adjusted to match the observed rates from 2011 (Scenario C) increased ozone by ∼4–5 ppb. Finally in Scenario D, the impact of additional NOx reductions was determined by assuming installation of selective catalytic reduction (SCR) controls on all units lacking postcombustion controls; this decreased ozone by an additional 2–4 ppb relative to Scenario A. Following the announcement of a stricter 8-hour ozone standard, this analysis outlines a strategy that would help bring coastal areas in the mid-Atlantic region closer to attainment, and would also provide profound benefits for upwind states where most of the regional EGU NOx originates, even if additional capital investments are not made (Scenario A).Implications: With the 8-hr maximum ozone National Ambient Air Quality Standard (NAAQS) decreasing from 75 to 70 ppb, modeling results indicate that use of postcombustion controls on coal-fired power plants in 2018 could help keep regions in attainment. By operating already existing nitrogen oxide (NOx) removal devices to their full potential, ozone could be significantly curtailed, achieving ozone reductions by up to 5 ppb in areas around the source of emission and immediately downwind. Ozone improvements are also significant (1–2 ppb) for areas affected by cross-state transport, especially Mid-Atlantic coast regions that had struggled to meet the 75 ppb standard.

Quantifying the impacts of sea-level rise on coastal biodiversity: A case study on lichens in the mid-Atlantic Coast of eastern North America

Preliminary, large-scale assessments of global sea-level rise (SLR) have predicted significant impacts to coastal and island biodiversity. Region-specific estimates of SLR impacts that incorporate accurate species distributions and local rates of SLR are now required for effective conservation planning. Here we use a dataset of >13,000 occurrence records for lichens, obligate symbiotic fungi, in the Mid-Atlantic Coastal Plain of eastern North America to model distributions of 193 species. The resulting models were used to quantify the amount of each species' distribution that is occupied by unsuitable land use types, along with the potential area that will be lost to SLR. We show that species have likely already lost an average of 32% of their distributional area to development and agriculture, and are predicted to lose an average of 12.4 and 33.7% of their distributional area with one foot (~0.3m) and six feet (~1.8m) of SLR, respectively. Functional and taxonomic groups were compared to identify specific effects of SLR. We show that species reproducing with symbiotic propagules have significantly larger distributions than species that reproduce sexually with fungal spores alone, and that the sexually reproducing species are predicted to lose greater distributional area to SLR. Cladonia species occupy significantly less area in the MACP than Parmotrema species and are predicted to lose more of their distributions to SLR. We further examined patterns of total species diversity and found that the area with the highest diversity is the Dare Peninsula in North Carolina, which is also predicted to lose the most land area to SLR. The workflow established here is flexible and applicable to estimating SLR impacts worldwide and can provide essential insights for local conservation planning.

Decadal changes in zooplankton abundance and phenology of Long Island Sound reflect interacting changes in temperature and community composition

Between 1939 and 1982, several surveys indicated that zooplankton in Long Island Sound, NY (LIS) appeared to follow an annual cycle typical of the Mid-Atlantic coast of North America. Abundance peaked in both early spring and late summer and the peaks were similar in magnitude. In recent decades, this cycle appeared to have shifted. Only one large peak tended to occur, and summer copepod abundance was consistently reduced by ∼60% from 1939 to 1982 levels. In other Mid-Atlantic coastal systems such a dramatic shift has been attributed to the earlier appearance of ctenophores, particularly Mnemiopsis leidyi, during warmer spring months. However, over a decade of surveys in LIS have consistently found near-zero values in M. leidyi biomass during spring months. Our multiple linear regression model indicates that summer M. leidyi biomass during this decade explains <25% of the variation in summer copepod abundance. During these recent, warmer years, summer copepod community shifts appear to explain the loss of copepod abundance. Although Acartia tonsa in 2010–2011 appeared to be present all year long, it was no longer the dominant summer zooplankton species. Warmer summers have been associated with an increase in cyanobacteria and flagellates, which are not consumed efficiently by A. tonsa. This suggests that in warming coastal systems multiple environmental and biological factors interact and likely underlie dramatic alterations to copepod phenology, not single causes.

Migratory Status, Winter Subspecies Interactions, and Habitat Segregation of Atlantic Song Sparrows (Melospiza melodia atlantica)

ABSTRACT We performed the first winter surveys of the Atlantic Song Sparrow (Melospiza melodia atlantica), a poorly known subspecies that is endemic to sand dunes of the mid-Atlantic coast. Novel findings include that the Atlantic Song Sparrow is a year-round resident or partial migrant, primarily flocks with the same subspecies despite occurring in sympatry with the eastern Song Sparrow (M. m. melodia) in winter, and exhibits age-specific habitat use in winter, with immatures greatly outnumbering adults in adjacent saltmarshes. These results are important for conservation planning and understanding the ecology and evolution of this unique subspecies across the annual cycle.

Short Communications

Few details are available on the migration (rates, routes, dates) of Neotropical austral migrant birds, which breed and migrate wholly within South America. Only one long-distance austral migrant breeds in the South American temperate forest biome: the White-crested Elaenia (Elaenia albiceps chilensis). However, the migratory dates, routes, and wintering locations are poorly known. During the austral summers of 2011–2013, we attached light level geolocators to breeding White-crested Elaenias at the world’s southernmost forests, on Navarino Island, Chile. The duration of fall migration of three Elaenias to the Amazonian wintering grounds was 64–96 days, while spring migration was 45–60 days. The average distance between breeding and wintering grounds was 5,932 km, which constitutes the longest migration of a Neotropical austral migrant studied to date. A better understanding of the annual cycle of Elaenias could offer new opportunities to examine the evolution of migration and population regulation of one of Patagonia’s most common birds.Native bird diversity is compromised in urban areas partially because of the lack of available habitat for some species. As urbanization continues to increase, it is important to understand the behavioral dynamics of bird species located in cities. The Black-capped Chickadee (Poecile atricapillus), as a generalist species, offers an opportunity to investigate how common native birds use urban areas that lack natural habitat features while additionally competing with non-native, invasive species (e.g., House Sparrows, Passer domesticus). Our objectives were to determine nest box use and nesting success rate of Black-capped Chickadees and House Sparrows using artificial nest boxes in natural habitats located in an urban area, specifically a recently restored 5.66- ha area of pond sedge surrounded by oak (Quercus spp.) savannah located south of Lincoln Park Zoo in Chicago, Illinois, USA. Artificial nest cavities with 3 cm diameter entrance holes, intended to exclude House Sparrows, were installed on trees around the study site and monitored for activity. We found that Black-capped Chickadees will readily use artificial cavities; seven of the 20 boxes were excavated and four produced nests. The artificial nesting cavities successfully excluded House Sparrows from nest building and raising young.Bank Swallows (Riparia riparia) congregate in large nocturnal roosts during the non-breeding season. Scant evidence suggests that Bank Swallows may also congregate regularly in nocturnal roosts during the breeding period. To help clarify the issue, we used automated radio-telemetry to document the roosting behavior of 11 males and 11 females that were tending nests with young at two nesting colonies. Nineteen of the 22 birds (86%) spent at least one night roosting away from the colony, and 13 of the 22 birds (59%) spent at least one night roosting likely within a large marsh located ~30 km away from the colonies. Females tended to roost overnight at the colony more than males. The proportion of nights birds spent roosting away from the colony was highly variable between individuals. Minimum flight speeds to an evening roost site (~30 km distant) were significantly greater than return flights back to the colony in the morning. Our study confirms that breeding Bank Swallows do in fact regularly roost away from the colony during the nestling period. Our study also highlights some new and intriguing questions regarding how Bank Swallows use the landscape during the breeding season, and the potential importance of wetland roost sites in the proximity of breeding colonies.We performed the first winter surveys of the Atlantic Song Sparrow (Melospiza melodia atlantica), a poorly known subspecies that is endemic to sand dunes of the mid-Atlantic coast. Novel findings include that the Atlantic Song Sparrow is a year-round resident or partial migrant, primarily flocks with the same subspecies despite occurring in sympa

Gap Filling of the Coastal Ocean Surface Currents from HFR Data: Application to the Mid-Atlantic Bight HFR Network

AbstractHigh-frequency radar (HFR) surface current data are an increasingly utilized tool for capturing complex dynamics of coastal ocean systems worldwide. The radar is uniquely capable of sampling relevant temporal and spatial scales of nearshore processes that impact event response activities and basic coastal ocean research. HFR is a shore-based remote sensing system and is therefore subject to data gaps, which are predominately due to environmental effects, like increased external noise or low signal due to ocean surface conditions. Many applications of these surface current data require that these gaps be filled, such as Lagrangian numerical models, to estimate material transport and dispersion. This study introduces a new penalized least squares regression method based on a three-dimensional discrete cosine transform method to reconstruct hourly HFR surface current data with a horizontal resolution of 6 km. The method explicitly uses both time and space variability to predict the missing value. Furthermore, the method is fast, robust, and requires relatively low computer memory storage. This paper evaluates the method against two scenarios of common data gaps found in HFR networks currently deployed around the world. The validation is based on observed surface current maps along the mid-Atlantic coast of the United States with specific vectors removed to replicate these common gap scenarios. The evaluation shows that the new method is robust and particularly well suited to fill a more common scenario with complete data coverage surrounding an isolated data gap. It is shown that the real-time application of the method is suitable for filling data gaps in large oceanography datasets with high accuracy.