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Predation management is an important component of managing species of conservation concern. The piping plover (Charadrius melodus; plover), a disturbance-dependent and conservation-reliant shorebird that nests on sandy beaches and barrier islands on the Atlantic Coast, was listed under the United States Endangered Species Act in 1986, with habitat loss and predation stated as key causes of its decline. We evaluated the relationship between a suite of predators and plover chick survival from 2015-2018. We used a camera grid to establish indices of the abundance of 3 known chick predators: red fox (Vulpes vulpes), raccoon (Procyon lotor), and domestic cat. We used camera detections in a survival model to assess potential relationships between predator species detection and plover chick survival. Plover chick survival was negatively related with red fox detection, but not with detection of the other 2 predators. In addition to the correlation with red fox detections, chick survival was negatively related to high plover nesting density. Our results suggest that red foxes were predators of piping plover chicks during our study, likely augmented by other density-dependent sources of mortality. Targeted predator management could aid in conservation of piping plovers in this system as a short-term solution, but long-term recovery plans must also address habitat limitation. [ABSTRACT FROM AUTHOR]

North America's northernmost, sizable colony of Caspian Terns (Hydroprogne caspia) is located on the Copper River Delta of south-central Alaska, USA. The colony was monitored in June during 2008-2016 and in July during 2009-2013. This 9-year period coincided with reduction of Caspian Tern nesting habitat at East Sand Island in the Columbia River estuary, Oregon, USA, one of the world's largest Caspian Tern breeding colonies. The number of active nests on the Copper River Delta more than doubled during the early study period from 209 in 2008 to 423 in 2013. However, there was a steady decline in the number of nests during 2014 (281) to 2015 (115) and the colony failed in 2016. These declines were likely due to warm sea surface temperature anomalies across the northeastern Pacific Ocean in those years. Based on resightings of banded individuals, colony connectivity was documented between the Copper River Delta and other colonies, ranging from southeast Alaska (215 km) to central California, USA (> 3,000 km). The East Sand Island colony was the most important source of immigrants to the Copper River Delta. While the Copper River Delta now serves as important natural breeding habitat for Caspian Terns, increased flooding and severe storms associated with climate change will likely limit colony size and productivity in the long-term. [ABSTRACT FROM AUTHOR]

Raccoons (Procyon lotor) are important predators of ground-nesting species in coastal systems. They have been identified as a primary cause of nest failure for the American Oystercatcher (Haematopus palliatus) throughout its range. Concerns over the long-term effects of raccoon predation and increased nest success following a hurricane inspired a mark-resight study of the raccoon population on a barrier island off North Carolina, USA. Approximately half of the raccoons were experimentally removed in 2008. Nests (n = 700) were monitored on two adjacent barrier islands during 2004-2013. Daily nest survival estimates were highest for 2004 (0.974 ± 0.005) and lowest for 2007 and 2008 (0.925 ± 0.009 and 0.925 ± 0.010, respectively). The only model in our candidate set that received any support included island and time of season, along with a diminishing effect of the hurricane and a constant, 5-year effect of the raccoon removal. For both hurricane and raccoon removal, however, the support for island-specific effects was weak (β = -0.204 ± 0.116 and 0.146 ± 0.349, respectively). We conclude that either the raccoon reduction was inadequate, or factors other than predation cause more variation in nest success than previously recognized. A multi-faceted approach to management aimed at reducing nest losses to storm overwash, predation, and human disturbance is likely to yield the largest population level benefits. [ABSTRACT FROM AUTHOR]

Sea-level rise, a dominant driving force of change for coastal regions, is becoming increasingly important as a hazard to humans and urban areas in the coastal zone worldwide as global climate change takes effect. The geologic record shows that sea level, due to past natural climate factors, has been highly variable, as much as 6-8 m higher than present during the last interglacial warm period and 130 m lower during the last glacial period. Sea level was fairly stable for the past 3,000 years until about the mid-19th century. During the 20th century, sea level began rising at a global average rate of 1.7 mm/yr. The current average rise rate is 3.1 mm/yr, a 50% increase over the past two decades. Many regions are experiencing even greater rise rates due to local geophysical (e.g., Louisiana, Chesapeake Bay) and oceanographic (Mid-Atlantic coast) forces. A few regions experience rise rates less than the global average due to land uplift. Observations show the increase of carbon emissions since the Industrial Revolution has increased global mean temperature of the air and ocean, which is responsible for sea-level rise due to ice sheet melting and steric expansion, and many related environmental changes. Sea-level rise, with high regional variability, is exhibiting acceleration and is expected to continue for centuries unless mitigation is enacted to reduce atmospheric carbon. Low-lying coastal plain regions, deltas, and most islands are highly vulnerable. Adaptation planning on local, state and national scales for projected sea-level rise of 0.5-2 m by A.D. 2100 is advisable. Sustained global rise in sea level of 4 m to as much as 8 m is possible, but not likely until well after A.D. 2100. [ABSTRACT FROM AUTHOR]

Maritime forest communities on barrier islands along the Atlantic and Gulf coasts have been severely fragmented by a continuous history of human land use and natural disturbance. Isolated populations of certain tree species in maritime forest fragments may now be too small to be viable and their inability to regenerate may result in their eventual elimination from barrier islands. Using an 11-year study of a population of pignut hickory (Carya glabra), a common species of remnant maritime forest stands on St. Catherine's Island, Georgia, we present a case study of tree regeneration failure on a barrier island. We found that there has been no recruitment of new hickory individuals into the canopy of this population over the last 65 years. Field evidence of browse and a strong correlation between seedling density distributions and microsite protection from herbivory suggest that this trend in recruitment failure is related to an increased abundance of deer (Odocoileus) and pigs (Sus) on the island. Using a size class population projection model, we estimated that, if such recruitment failure and mortality rates continue, the hickory population will be extirpated from the maritime forest within 200 years. Tree species that are failing to regenerate within maritime forests represent a special challenge that is not currently being addressed in the long-term management of barrier island biodiversity. [ABSTRACT FROM AUTHOR]

Abstract: The Outer Banks barrier islands of North Carolina, USA, contain a geologic record of inlet activity that extends from ca. 2200calyr BP to the present, and can be used as a proxy for storm activity. Optically stimulated luminescence (OSL) dating (26 samples) of inlet-fill and flood tide delta deposits, recognized in cores and geophysical data, provides the basis for understanding the chronology of storm impacts and comparison to other paleoclimate proxy data. OSL ages of historical inlet fill compare favorably to historical documentation of inlet activity, providing confidence in the technique. Comparison suggests that the Medieval Warm Period (MWP) and Little Ice Age (LIA) were both characterized by elevated storm conditions as indicated by much greater inlet activity relative to today. Given present understanding of atmospheric circulation patterns and sea-surface temperatures during the MWP and LIA, we suggest that increased inlet activity during the MWP responded to intensified hurricane impacts, while elevated inlet activity during the LIA was in response to increased nor''easter activity. A general decrease in storminess at mid-latitudes in the North Atlantic over the last 300yr has allowed the system to evolve into a more continuous barrier with few inlets. [Copyright &y& Elsevier]

Abstract: Nearly 200 km of high-resolution ground penetrating radar (GPR) data were acquired along the Outer Banks barrier island system of North Carolina, USA. GPR data combined with lithofacies and biofacies data reveal multiple depositional facies including inlet channel, flood-tide delta, overwash, peat and inner shelf. Previously undocumented paleo-inlet channels constitute a significant portion of the shallow geologic framework between Oregon Inlet and Cape Hatteras. GPR data reveal the complex stratigraphy associated with multiple sequences of cut-and-fill within inlet channels. Two types of paleochannels (non-migrating and migrating) were classified based on geometry and fill-patterns. Sediments and foraminifera collected from vibracores were correlated to GPR data to define the regional shallow stratigraphic framework. Channel-fill facies are characterized by clinoform packages, sometimes bounded by erosional surfaces, indicating variable sediment transport directions from the ocean and sound sides. Channels are incised into older flood-tide delta deposits corresponding to older inlet activity when barriers existed further seaward. Flood-tide delta deposits are capped with marsh peat and overwash units. Migrating inlet facies occur under the widest portions of the island, whereas narrow portions of the island are underlain by the non-migrating inlet facies or flood-tide delta/overwash facies. This geologic/geomorphic relationship is attributed to the successional stage of island evolution during transgression, and sediment transport processes associated with the different inlet types. The radar facies, lithofacies, and biofacies provide a comprehensive dataset that will permit more precise identification of barrier island facies in the geologic record. [Copyright &y& Elsevier]

Abstract: Imagery of ecological systems can be used to observe organisms, to observe rare events and to document long-term changes in ecological systems. Here we describe two systems used for archiving and sharing imagery with ecological researchers in the United States and Taiwan, discuss the database design and interface issues and how they were resolved and present some examples of their use. The Shan-Ping Bee Camera System monitors a bee colony at the Shan-Ping Forest Ecological Garden in south-central Taiwan. The Virginia Ecocam System uses wirelessly-connected web cameras to capture imagery from remote barrier islands of the Virginia Coast Reserve. Both systems provide multiple tools to retrieve and display images for research use using a relational database to store and query image metadata, but store the images in either a file system or using a Storage Resource Broker (SRB). [Copyright &y& Elsevier]

Forty-nine vibracores were collected from a barrier island shoreface following 12.4 years of biweekly profile surveying. The sedimentologic architecture of the shoreface was linked to time-series elevation change and profile shape to determine relationships between morphodynamics, facies development, erosional processes, profile closeout, and cross-shore transport.The modern shoreface mass, which erosionally overlies a tidal inlet-associated complex, attains a maximum thickness of 3–4 m below the beach to middle profile before pinching out seaward between 9 and 12 m depth. Concave erosional surfaces overlain by cross-stratified fine to medium sand and gravel make up most of the lower half of the shoreface prism below the beach through middle profile reflecting longshore trough incision and subsequent current-dominated aggradation. At the landward margin, gravel-rich laminae record episodic seaward progradation of beach surfaces over coarse inner-trough settings. Seaward, a parallel-laminated fine-sand facies dominates the upper part of the prism recording intermittent shoal zone buildup, including trough filling, under high-velocity plane-bed conditions. Similarly, a bioturbated parallel-laminated, fine- to very fine-sand facies makes up the entire prism below the outermost lower ramp sector, again indicating buildup under high-velocity conditions. However, accretion of the lower ramp results from major storms that cause trough scour along landward locations and simultaneous displacement of fine sand onto the lower ramp. Conversely, lower ramp erosion typically occurs during less energetic conditions as sediment is slowly returned shoreward causing inner-shoreface buildup. Close spacing of major storms during some years led to net progradation of the shoreface.The upper and lower limits of surveyed elevation change (ULe and LLe) repeatedly develop similar limit-profile shapes over shoreface accretion–erosion cycles. The ULe reflects accretion maxima resulting from beach, bar, and lower ramp buildup. The LLe and lower sedimentologic limit (LLs) along the inner 250 to 300 m of the active shoreface are a product of storm-trough scour down to a maximum depth of ∼5.5 m. Below the lower ramp facies, the LLe and LLs are primarily products of less energetic wave erosion down to ∼5 m (shoreward) and 9 m (offshore) depths. The LLe closely matches the LLs documenting that >90% of the shoreface prism was reworked during the 12.4-year period whereas actual ages for erosional events indicate a potential of 2 to 4 years for complete reworking of the shoreface mass. Textural distribution indicates net long-term transport direction and loci of deposition for different sized material. The coarsest material is concentrated at landwardmost locations and well-sorted fine to very fine sand at seaward locations. Medium sand to gravel tends to remain within the trough zone, even during extreme storm events. The ULe and LLe also represent the upper and lower limits for profile closure events. A location of about 4.5 m depth at 300 to 350 m from shoreline marks the boundary between inner profile- and lower ramp-associated closure events, the boundary between trough-associated and lower ramp facies, and the lower ramp morphologic break, all of which correspond to the juncture between longshore-current- and shoaling wave-dominated zones. The lower-ramp zone of closure is a zone of seaward decreasing storm transport in which fine to very fine sand is the typical bedload material. [Copyright &y& Elsevier]

A mathematical model is formulated to describe incipient breaching of coastal barrier islands. The model is based on the assumptions of idealized breach morphology and is intended to describe the growth of breaches prior to possible closure by longshore sediment transport. The two coupled, non-linear equations governing breach width and depth are solved analytically for special cases. The analytical solutions explicitly exhibit an exponential behavior in breach dimensions and reveal that the macroscale process of breach growth is controlled by seven variables: initial width and depth of the breach, equilibrium width and depth of the breach, width of the barrier island, and maximum or initial net sediment transport rates at the bottom and sides of the breach. The literature is reviewed to compile general properties of coastal breaches, and sensitivity testing shows the model to be compatible with those observations. The model is applied to simulate the 1980 breach at Moriches Inlet, New York, and reasonable agreement is found. [ABSTRACT FROM AUTHOR]

A regional study of the Holocene sequence onlapping the west-central Florida Platform was undertaken to merge our understanding of the barrier-island system with that of the depositional history of the adjacent inner continental shelf. Key objectives were to better understand the sedimentary processes, sediment accumulation patterns, and the history of coastal evolution during the post-glacial sea-level rise. In the subsurface, deformed limestone bedrock is attributed to mid-Cenozoic karstic processes. This stratigraphic interval is truncated by an erosional surface, commonly exposed, that regionally forms the base of the Holocene section. The Holocene section is thin and discontinuous and, north or south of the Tampa Bay area, is dominated by low-relief sand-ridge morphologies. Depositional geometries tend to be more sheet-like nearshore, and mounded or ridge-like offshore. Sand ridges exhibit 0.5–4 m of relief, with ridge widths on the order of 1 km and ridge spacing of a few kilometers. The central portion of the study area is dominated nearshore by a contiguous sand sheet associated with the Tampa Bay ebb-tidal delta. Sedimentary facies in this system consist mostly of redistributed siliciclastics, local carbonate production, and residual sediments derived from erosion of older strata. Hardground exposures are common throughout the study area. Regional trends in Holocene sediment thickness patterns are strongly correlated to antecedent topographic control. Both the present barrier-island system and thicker sediment accumulations offshore correlate with steeper slope gradients of the basal Holocene transgressive surface. Proposed models for coastal evolution during the Holocene transgression suggest a spatial and temporal combination of back-stepping barrier-island systems combined with open-marine, low-energy coastal environments. The present distribution of sand resources reflects the reworking of these earlier deposits by the late Holocene inner-shelf hydraulic regime. [Copyright &y& Elsevier]

Seaward-dipping strata of carbonate-cemented shell debris located along the coast of Siesta Key on the Gulf Coast of the Florida peninsula have long been interpreted to be beachrock equivalent in age to the Pleistocene Anastasia Formation (Stage 5e) of the east coast of Florida. Detailed examination of thin sections along with radiometric dating and isotopic analyses demonstrates clearly that this is a Holocene deposit that is not beachrock but was lithified in a meteoric environment. Whole rock dates, dates from shells only, and from cement only demonstrate that these beach deposits were in place by at least 1800 yr BP and might have been there as long ago as 4300 yr BP. This means that some type of barrier island was in place at that time. Previous investigations have depicted Siesta Key as having a maximum age of 3000 yr with these deposits being located about 2 km landward of the beach deposits. This suggests that the beach deposits might have been the site of the original position of Siesta Key. These data also indicate that sea level must have been near its present position at the time that these foreshore beach deposits were deposited; sometime between 1800 and 4300 yr ago. This scenario indicates that sea level along this coastal reach probably reached its present level at least about 2000 yr ago. [Copyright &y& Elsevier]

Although the morphology of the barrier-inlet system along the west-central Florida coast is quite complicated, the stratigraphy of these barriers is rather simple. The basal Holocene unit in most cores is an organic-rich, muddy sand that represents a vegetated, paralic marine, coastal environment similar to that which is north and south of the present barrier system. Above that unit is a muddy, bioturbated sand that displays a marine fauna at most locations but also contains Crassostrea virginica in a few places. These sediments accumulated in a low-energy marine setting that may or may not have been protected by a barrier island. Much of this facies also represents sediment that was delivered as washover deposits in an intertidal or subtidal setting and was subsequently bioturbated. The facies that can be attributed to a barrier island with some certainty are no more than 3000 years old, and on most islands, are much younger. These are the shelly sand and sorted sand facies. The shelly strata represent deposition in nearshore, beach, supratidal washover or intertidal spillover environments, and tidal inlet and tidal delta channels, whereas the sorted sand is typical of eolian deposition in dunes or the backbeach and some tidal delta elements. The presence of Holocene oyster beds offshore of a present barrier suggests that some of these islands formed significantly offshore and moved to their present position through washover. It is likely that most of these barriers initially formed through upward shoaling by waves. Although there is significant morphologic difference between the wave-dominated and mixed-energy, drumstick barrier islands, their stratigraphy is quite similar. The only significant difference is the presence of extensive progradation on at least part of the drumstick islands and a relatively high amount of former washover deposits on the wave-dominated type. [Copyright &y& Elsevier]

The characteristics of foredunes created in a municipal management program on a developed barrier island are evaluated to identify how landforms used as protection structures can be natural in appearance and function yet compatible with human values. Shoreline management zones include a naturally evolving, undeveloped segment; a noneroding, developed segment; eroding and noneroding segments of an “improved beach” where dunes have been built by artificial nourishment; and a privately built, artificially nourished dune on the shoreline of an inlet.A disastrous storm in 1962 resulted in an aggressive program for building dunes using sand fences, vegetation plantings, purchase of undeveloped lots, and sediment backpassing to maintain beach widths and dune elevations. The present nourished and shaped foredune in the improved beach is higher, wider, and closer to the berm crest than the natural dune. Restricted inputs of aeolian sand keep the surface flat and poorly vegetated. A stable section of this engineered shore has a wider beach, and sand fences have created a higher foredune with greater topographic diversity. The cross shore zonation of vegetation here is more typical of natural dunes, but the environmental gradient is much narrower. The privately built dune is low, narrow, and located where it could not be created naturally. Foreshore and aeolian sediments in the undeveloped segment and the improved beach are similar in mean grain size (0.16–0.21 mm) and sorting (0.31–0.39φ), but sediment on the surface of the nourished dune is coarser (28.1% gravel) with a more poorly sorted sand fraction (1.30φ) representing lag elements on the deflation surface.Willingness to enhance beaches and dunes for protection has reduced insurance premiums and allowed the municipality to qualify for funds from the Federal Emergency Management Agency (FEMA) to replace lost sediment, thus placing an economic value on dunes. Success of the management program is attributed to: (i) timing property-purchase and dune-building programs to periods immediately after storms (causing residents to accept high dunes that restrict access or views); (ii) instituting a vigorous education program (reminding residents of hazards during nonstorm periods); (iii) maintaining control over local sediment supplies (to keep pace with erosion and create new shoreline environments); (iv) investing private and municipal economic resources in landforms (qualifying them for external funds for replacement); and (v) maintaining, augmenting, or simply tolerating biodiversity and natural processes (retaining a natural heritage). [Copyright &y& Elsevier]

The role that barrier islands play in mitigating the wave climate inlower energy, bay or lagoonal environments as not yet been addressedin detail. With the exception of one study in which a shallow water wave prediction model (HISWA) (LIST et. al., 1992) was applied to idealized barrier-bay configurations, the critical linkages among barriers, wave energy transmission into bays, regenerated local waves, and subsequent wave climate have not been made. In Louisiana, barrier disintegration is rapid over the short-term (102 years) and the mere potential for impacts of barrier loss on the bay wave climate is highly significant. Because of a paucity in scientific data which could be utilized to address this issue, there remains a significant debate as to the value of barrier islands in mitigating wave climate in the bays and along fringing marshes. In this paper we present historical shoreline change data which are used to predict the rapid disintegrationof a section of barrier island coast along central Louisiana (Isles Dernieres) and resultant forecasted increases in wave energy in the adjacent bays. The methods associated with shoreline. bathymetric and wave energy forecasting are briefly presented as an example of a larger, ongoing project regarding the feasibility of large-scale barrier island restoration in Louisiana. A brief overview of the magnitude and causal mechanisms associated with wetland loss are provided in addition to the implications associated with barrier island loss and subsequent detrimental impacts on fringing marshes. The example data set presented here indicates that the role of Louisiana's barrier islandscomprising the Isles Dernieres in mitigating the wave climate in their adjacent bays and fringing marshes appears critical. Considering only fairweather conditions, the data indicate that the bays adjacent to the Isles Dernieres could experience an increase in wave height of700% if the barrier chain is reduced to shoals. Although large-scalebarri [ABSTRACT FROM AUTHOR]