EAARL-B coastal topography: Fire Island, New York, pre-Hurricane Sandy, 2012: seamless (bare earth and submerged)

ABSTRACT In October 2012, Hurricane Sandy caused severe erosion on beaches and dunes of Fire Island (New York, USA). Major shoreline changes occurred with erosional dominance in the upper shoreline and aggradation in the lowermost section of the beach due to the deposition of eroded upper-beach and dune sediment. Sand laminae with a high concentration of heavy minerals (“black sand laminae”) were observed in three excavated trenches located on a washover terrace and fan on the east side of Fire Island. The mineral composition of these laminae reveals the presence of high quantities of magnetite, ilmenite (as opaque minerals), and garnet (as the main translucent mineral). These heavy-mineral-enriched laminae were formed as waves eroded and transported sand from the primary dune and smaller relict dunes under specific hydrodynamic conditions that promoted grain sorting according to differences in size and specific gravity. Based on the concentrations of certain heavy minerals, the threshold for primarily density-driven sorting probably lies between the specific gravity of less dense opaque mineral (ilmenite, 4.7) and almandine (4.3), the most common transparent heavy mineral. The number of laminae and concentrations of heavy minerals vary between trenches on the overwash terrace and appear to be controlled by their distance from sediment sources. The trench with the greatest number of laminae and higher heavy-mineral concentrations is located farthest from the main dune but is just 10 m inland of a relict dune that acts as the primary source of sediment of the washover deposit in this trench. A conceptual model for deposition of heavy-mineral layers is presented based on geomorphological and sedimentological evidence allowing the definition of a density threshold.

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Piping Plover population increase after Hurricane Sandy mediated by immigration and reproductive output

The Condor ◽

10.1093/condor/duaa041 ◽

2020 ◽

Author(s):

Samantha G Robinson ◽

Daniel Gibson ◽

Thomas V Riecke ◽

James D Fraser ◽

Henrietta A Bellman ◽

...

Keyword(s):

New York ◽

Population Growth ◽

Reproductive Output ◽

Hurricane Sandy ◽

Population Increase ◽

Piping Plover ◽

Habitat Creation ◽

Fire Island ◽

Large Scale Disturbance ◽

Positive Population

Abstract Evaluating population-level responses to conservation action following large-scale disturbance can improve the efficacy of future habitat conservation measures. In October 2012, Hurricane Sandy storm surges cleared vegetation and opened inlets through the barrier islands, Fire Island and Westhampton Island, New York, creating Piping Plover (Charadrius melodus) habitat. Storm effects prompted an island-wide stabilization project, which had the potential to negatively affect novel Piping Plover habitat. Certain sections of Fire Island were designed to create and/or improve habitat (hereafter, restoration areas) to mitigate possible habitat loss or degradation. Since Piping Plovers in New York appear to be habitat-limited, we anticipated positive population growth following habitat creation. From 2013 to 2018, we captured and banded 152 adults and 353 chicks, and monitored 279 nests and 160 broods. We developed an integrated population model to assess demographic processes in response to hurricane created-habitat (2013–2018) and the creation of restoration areas (2015–2018). We observed positive population growth in 3 of 5 yr, and overall growth throughout the period (λ¯ = 1.13). Immigration and reproductive output were correlated with population growth (r = 0.92 [95% CI: 0.22 to 0.98] and 0.84 [95% CI: –0.47 to 0.95], respectively). Compared with the rest of the study area, restoration areas had higher chick survival, and lower nest survival and after second-year site fidelity. The result was population growth in restoration areas (λ¯= 1.14) similar to the whole study area. In the short term, restoration areas seemed to mimic natural Piping Plover habitat. Vegetation removal, an important process in renewing natural Piping Plover habitat, likely will be necessary to maintain habitat suitability. Efforts to increase immigration of new breeding adults into the system, and to improve reproductive output, primarily by habitat creation or maintenance, are likely to have the greatest local effect on population growth.

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