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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 ( = 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 ( = 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.LAY SUMMARYDespite being listed under the Endangered Species Act for more than 30 yr, and intensive management, Piping Plovers on the Atlantic Coast have not met population recovery goals across much of their breeding range.Hurricane Sandy increased available nesting habitat (dry sand) by over 150%. Following Hurricane Sandy, we monitored a population of individually marked birds on Fire Island and West Hampton Island, New York, for 6 yr. The area monitored included restored habitat, to evaluate the effectiveness of Piping Plover targeted habitat management.The population increased 90% in the 6 yr following Hurricane Sandy, primarily because of immigrant adults, and local reproductive success. The reproductive output and population growth in restoration areas were similar to the rest of the study area.Overall, Hurricane Sandy habitat creation was positive for this local plover population.Efforts to allow future hurricane storm surges to create habitat, along with continued management, will improve long-term population persistence.

Species listed under the U.S. Endangered Species Act are required to meet stated recovery goals for delisting. These goals often are developed early in the species’ conservation history and may need to be updated or refined as new information becomes available. The Atlantic Coast Piping Plover (Charadrius melodus), which was listed more than 30 yr ago, has not met recovery goals through much of its range. Initial recovery goals included maintaining a reproductive output of 1.5 fledged chicks per pair for 5 yr. This goal was based on modelling that assumed equal survival rates for adults throughout the range, but recent studies suggest that demographic rates may vary with latitude. To investigate latitudinal variation, we developed demographic and population growth estimates for 2 breeding populations of Piping Plovers on the U.S. Atlantic Coast on Fire Island, New York (40.7°N), and on the Outer Banks of North Carolina (35.3°N) in 2013–2017. Breeding success (nest success and pre-fledge chick survival) varied annually but was lower in North Carolina than New York. Average adult true survival in New York (x̅ = 0.73, SE = 0.04) was similar to average survival in North Carolina (x̅ = 0.69, SE = 0.07). Annual post-fledging survival for both sites, however, was variable and often higher than had been previously reported for Atlantic Coast Piping Plovers (0.43–0.66 for New York; 0.31 and 1.0 for North Carolina). While the estimated reproductive output needed for a stationary population for both sites was similar (1.10 chicks per pair for New York, 95% CI: 0.83–1.41; 1.08 for North Carolina, 95% CI: 0.67–1.59), only the New York population achieved or exceeded these values during our study. Our findings suggest that understanding annual and latitudinal demographic variability would be helpful in refining recovery goals.

All ecological measurements are subject to error; the effects of missed detection (false negatives) are well known, but the effects of mistaken detection (false positives) are less understood. Long-term capture–recapture datasets provide valuable ecological insights and baselines for conservation and management, but where such studies rely on noninvasive re-encounters, such as field-readable color bands, there is the potential to accumulate detection errors as the length of the study and number of tags deployed increases. We investigated the prevalence and effects of misreads in a 10-yr dataset of Red Knots (Calidris canutus rufa) marked with field-readable leg flags in Delaware, USA. We quantified the effects of misreads on survival estimation via a simulation study and evaluated whether removal of individuals only reported once in a year (potential misreads) influenced survival estimation from both simulated datasets and our case study data. We found overall apparent error rates of 0.31% (minimum) to 6.6% (maximum). Observer-specific error rates and the variation among observers both decreased with the number of flags an observer recorded. Our simulation study showed that misreads lead to spurious negative trends in survival over time, particularly for long-term studies. Removing all records in which a flag was only recorded once in a sampling occasion reduced bias and eliminated spurious negative trends in survival but also reduced precision in survival estimates. Without data filtering, we found a slight decrease in Red Knot annual survival probability from 2008 to 2018 (β = −0.043 ± 0.03), but removing all single-observation records resulted in no apparent trend (β = −0.0074 ± 0.02). Spurious trends in demographic rates could influence inference about population trajectories and resultant conservation decision-making. Data filtering could eliminate errors, but researchers should carefully consider the tradeoff between precision obtained by larger sample sizes and potential bias due to misreads in their data.

Between April 2014 and August 2015, we observed 4 Charadrius melodus (Piping Plover) consume small, dead fish, including Anchoa mitchilli (Bay Anchovy) on New York barrier islands. These observations are among the first documented evidence of vertebrate prey in Piping Plover diets. While fish consumption is an opportunistic and infrequent occurrence, this behavior may supplement important nutrients in the diet of Piping Plovers in areas without access to high-quality food resources. Further diet analyses are necessary to understand the importance and relative contribution of fish as a prey resource for endangered Piping Plovers.

Increasing attention is paid to the effects of human activities, including the use of aircraft, on wildlife. However, responses to visual and auditory stimuli associated with aircraft are highly species- and context-dependent and results of existing studies should not be generalized across species, or even across life stages of the same species. We used digital audio recorders, auto-triggered cameras, and heart rate monitors to study the responses of nesting Wilson's plovers (Charadrius wilsonia) to different types of planes (civilian and military fixed-wing aircraft) and helicopters (civilian and military rotary-wing aircraft) at Cape Lookout National Seashore, North Carolina. We compared vigilance behavior, incubation rate, and heart rate before, during, and after overflights. Wilson's plovers were alert and scanned more during military rotary-wing overflights, and scanned more during both military and civilian fixed-wing overflights than during periods without overflights. Heart rates and incubation rates did not change during any type of overflights. Although we found no direct link between increased vigilance rates and decreased reproductive success, a substantial increase in aircraft traffic at our study site, especially rotary-wing overflights, would merit further investigation. © 2015 The Wildlife Society.

Because of the variability in the types of human activities to which animals are exposed and the associated responses by different species, there is a lack of consensus on the effects of humans on wildlife behavior. We studied the effects of military air traffic, all-terrain vehicles, off-road vehicles, and pedestrians on the nesting behaviors of least terns (Sternula antillarum), common terns (Sterna hirundo), gull-billed terns (Gelochelidon nilotica), and black skimmers (Rynchops niger) at North Core Banks, Cape Lookout National Seashore (CALO), North Carolina. We deployed digital audio recorders and time-lapse cameras within 9 colonies from May to August 2010–2011 and sampled nesting behaviors before, during, and after human activities. There was no evidence that military or civilian aircraft adversely affected incubation behavior for any of the focal species. The mean incubation rate by least terns was less during pedestrian events than control periods (91% vs. 79%, S = −2.2, P = 0.04). The current patterns of aircraft operations are unlikely to affect colonial waterbird demographics. Current beach management policies restricting human activity to >50 m from colony boundaries mitigated adverse impacts to nesting colonial waterbirds. © 2015 The Wildlife Society.

Despite concerns about their population status, information about the habitat preferences, population size, and vital statistics of Wilson's Plovers (Charadrius wilsonia) is currently lacking. We compared habitat characteristics of nest sites and unused sites and examined factors affecting nest success on a barrier island in North Carolina in 2010 and 2011. We monitored 83 nests with cameras and added heart-rate monitors in artificial eggs to 36 of these nests for a concurrent study of the effects of jet overflights; predator exclosures were placed around 17 of the nests with cameras. Wilson's Plovers used interdune areas, flats, and isolated dunelets on flats more than expected based on availability, and nests were located closer to dense vegetation than unused sites. Nests in interdune areas had higher daily survival rates than nests on flats, but distance to dense vegetation did not affect nest survival. Nests without cameras, heart-rate monitors, or exclosures had a 35% predicted probability of hatching at least one egg. Exclosed nests had higher daily survival rates than nests without exclosures, but daily survival rates were lower for nests with cameras or heart-rate monitors and for nests initiated later in the season. Daily survival rates also declined as nests aged. The predicted probability of fledging was 74%, resulting in a reproductive output of 0.78 fledglings/pair. Apparent annual adult survival was 77%, and the apparent annual survival rate for birds banded as chicks was 42%. Additional research is needed throughout the range of Wilson's Plovers to determine if populations are stable or decreasing, and to predict the productivity rates needed to maintain current populations. However, our results suggest that in our study area, predator removal and protection of sparsely vegetated overwash habitats will likely have the greatest impact on reproductive output. RESUMEN Eleccion de sitio de nidada y demografia del Chorlo de pico grueso en una isla barrera de Carolina del Norte A pesar de la preocupacion por su estatus poblacional, informacion sobre las preferencias de habitat, el tamano poblacional, y parametros de historia de vida del Chorlo pico grueso (Charadrius wilsonia) esta aun ausente. Comparamos las caracteristicas de habitat de sitios con nido y sitios sin uso y examinamos factores que afectan al exito de nidada en una isla barrera de Carolina del Norte en 2010 y 2011. Monitoreamos 83 nidos con camaras y agregamos monitores de la frecuencia cardiaca en huevos artificiales a 36 de los nidos para un estudio simultaneo del efecto del sobrevuelo de aviones; excluidores de predadores fueron colocados alrededor de 17 de los nidos monitoreados con camaras. Los Chorlos de pico grueso utilizan areas interdunares, areas planas, y pequenas dunas aisladas en areas planas mas de lo esperado basandose en la disponibilidad, y los nidos fueron construidos mas cerca de vegetacion densa que los sitios sin uso. Los nidos en areas interdunares tuvieron una tasa de supervivencia mas alta que los nidos en areas planas, pero la distancia a vegetacion densa no afecto la tasa de supervivencia de los nidos. Los nidos sin camaras, monitores de la frecuencia cardiaca, o excluidores de predadores tuvieron un 35% de probabilidades de eclosion de al menos un huevo. Los nidos excluidos de predadores tuvieron una tasa de supervivencia diaria de nido mas alta que los nidos sin excluidores, pero la tasa de supervivencia diaria fue menor para nidos con camara o con sensores de frecuencia cardiaca y para nidos iniciados tarde en la temporada reproductiva. La tasa de supervivencia diaria tambien declino al aumentar la edad del nido. La probabilidad predicha de volantones fue 74%, resultando en un rendimiento reproductivo de 0.78 volantones/par. La supervivencia anual aparente de adultos fue del 77%, y la tasa de supervivencia anual aparente para aves anilladas de pichones fue del 42%. Estudios adicionales son necesarios a lo largo de todo el rango de distribucion del Chorlo pico grueso para determinar si las poblaciones son estables o estan declinando, y para predecir las tasas de productividad necesarias para mantener las poblaciones actuales. Aun asi, nuestros resultados sugieren que, en nuestra area de estudio, la remocion de predadores y la proteccion marismas altas escasamente vegetadas probablemente tendran el mayor impacto en el rendimiento reproductivo.

There are two recognized subspecies of the Piping Plover (Charadrius melodus): the Atlantic coast United States and Canada (‘Atlantic’) subspecies and the Great Lakes and Northern Great Plains (‘Interior’) subspecies. More than 7,000 Piping Plovers have been banded and monitored since 1982, yet no individual marked as a hatchling or breeding adult in the range of one subspecies has been reported breeding in the range of the other. Recent molecular genetic analyses further support subspecific taxonomic classification of Atlantic and Interior breeding populations. On 22 May 2011, a banded Piping Plover and unbanded mate were observed nesting on North Core Banks, Cape Lookout National Seashore, North Carolina, USA. The uniquely-banded adult was a female captured as a chick at Wasaga Beach, Georgian Bay, Ontario, Canada; the female nested unsuccessfully in its first breeding year at Tawas Point State Park, Michigan, USA and then successfully fledged two chicks in its second breeding year at North Co...