Despite habitat perturbations and seasonal fluctuations in reproduction, many studies report no significant inter-annual variation in Great Egret reproductive performance. I examined the reproductive performance of Great Egrets (Ardea alba) for two breeding seasons (2009 and 2010) immediately following Hurricane Ike at High Island, Texas. Breeding success, productivity, and mean brood size did not differ between years (U-test, P > 0.05). Fledging success at 21 days showed no significant difference between years, however fledging success at 28, 35, and 42 days decreased significantly between years (~15% reduction at 42 days; U-test, P = 0.027). The number of deaths per nest also differed significantly between 2009 and 2010 (0.36 and 0.95, respectively) (U-test, P = 0.013). Brood-size dependent mortality was also a significant between-year parameter (H test, P = 0.003). Successful nests in 2009 had a brood size range of 2 to 3, and of these nests, 6% and 50% experienced partial brood reduction, respectively; whereas 2010 brood size range for successful nests was 2 to 4, and 0%, 57%, and 100% of these nests, respectively, experienced partial brood reduction. Other parameters examined were water level, temperature, precipitation, prey availability, and human disturbance. I rejected my hypothesis that habitat conditions would be less conducive to high reproductive success in 2009 than 2010, due to the impacts of Hurricane Ike. My results suggest that Great Egrets have bimodal occurrences of nestling death that are expressed as a function of brood size, hatching spread, and nestling age. Reproductive performance studies should continue through at least fledging age (42 days post-hatching for Great Egrets) to better document the reproductive performance, especially by incorporating the apparent behavioral plasticity of nestlings.

No description available.

No description available.

The piping plover (Charadrius melodus) is an imperiled migratory shorebird that nests on mainland and barrier island beaches on the Atlantic coast of North America. Its population decline was attributed to habitat loss, predation, coastal development, and disturbance. Hurricane Sandy reached the Northeast United States in October, 2012. The storm breached and overwashed two barrier islands of New York that support breeding piping plovers, Fire Island and Westhampton Island. In response to geomorphic island changes, the U.S. Army Corps of Engineers stabilized the islands by filling breaches, building dunes, and nourishing beaches. In accordance with the U.S. Fish and Wildlife Service and the Endangered Species Act, the U.S. Army Corps of Engineers constructed piping plover nesting habitat to mitigate the loss of habitat from engineering. The objectives of this study were to assess habitat selection and quantify suitable habitat before and after Hurricane Sandy and to investigate survival and migration of fledgling piping plovers within their first year. We studied piping plover nest-site selection, habitat, and abundance before (2010) and after (2015) Hurricane Sandy and engineered response. Before the storm, piping plovers selected nest sites (n=62) farther from the ocean (x̄ least-cost distance = 82.8 m) and bay (x̄ Euclidean distance = 697.7 m; x̄ least-cost distance = 24,160.6 m) than would be expected if they were selecting nest sites at random. Following the storm, piping plovers selected nest sites (n=45) that were close to, and had unobstructed walking access to, the ocean (x̄ least-cost distance = 123.4 m) and newly-created bayside foraging habitats (x̄ Euclidean distance = 468.0 m; x̄ least-cost distance = 728.9 m). Areas overwashed by the hurricane contained the most suitable piping plover habitat across all new habitat types. Piping plover abundance increased 93% by 2018 from pre-Hurricane Sandy abundances, with most pairs nesting in new habitats. However, only 58% of suitable piping plover habitat was protected from recreational use and only 4% of piping plovers used unprotected habitats for nesting during 2015–2017. We assessed post-fledging survival with radio telemetry and mark-recapture methods. We banded and monitored 292 fledged chicks from 2013–2018. We affixed nanotags to 43 pre-fledged chicks and tracked them to document mortality on their natal grounds. We used a multi-state open robust design model to estimate post-fledging survival within the first year and migration and return probabilities. Daily survival rate as estimated with nanotags was the same as estimated with mark-recapture methods (0.997). Post-fledging survival did not vary in the six years following the storm, nor did it vary across stages within an individual's first year (0.36; 95% CI = 0.31–0.42). Fledgling migration occurred between July 1 and September 22 and reached its peak between August 15–23 (Ψ = 0.97, 95% CI: 0.92–0.98). Individuals with earlier fledge dates migrated earlier (β = ˗1.51, 95% CI: ˗1.11–˗1.91). Second-year plovers returned to the breeding grounds between February 20 and May 8, with a peak occurring in late April and early May (Ψ = 0.55, 95% CI: 0.41–0.70). Given that newly-created storm and engineered habitats benefitted nesting and brooding plovers, ensuring protection of these and other suitable habitats would likely safeguard fledglings that persist on Fire Island for more than a month before departure. / Master of Science / The federally threatened piping plover (Charadrius melodus) is a migratory shorebird that breeds on sandy beaches along the Atlantic coast of North America. Coastal development, recreational use, and habitat loss are major factors that contributed to its listing under the Endangered Species Act in 1986. Hurricane Sandy reached the Northeast United States in October, 2012. The storm breached and overwashed Fire Island and Westhampton Island, prompting the U.S. Army Corps of Engineers to stabilize the islands by filling breaches, building dunes, and nourishing beaches. Because the islands support a breeding population of piping plovers, the U.S. Army Corps of Engineers also constructed piping plover habitat to mitigate the loss of habitat due to engineering. The objectives of this study were to assess habitat selection of plovers before and after Hurricane Sandy and to investigate survival and migration of fledgling piping plovers within their first year. We studied piping plover nest-site selection, suitable habitat, and abundance before (2010) and after (2015) Hurricane Sandy and engineered response. Before the storm, piping plovers selected nest sites farther from the ocean and bay than would be expected if they were selecting nest sites at random. Following the storm, piping plovers selected nest sites that were close to, and had unobstructed walking access to, the ocean and newly-created bayside foraging habitats. Areas overwashed by the hurricane contained the most suitable piping plover habitat across all new habitat types. Piping plover abundance increased 93% by 2018 from pre-Hurricane Sandy abundances, with most pairs nesting in new habitats. However, only 58% of suitable piping plover habitat was protected from recreational use and few piping plovers used unprotected habitats for nesting. From 2013–2019, we monitored post-fledging piping plovers through their first year. We estimated post-fledging survival and estimated fall and spring migration timing. Post-fledging survival was constant across their first year of life. Fledgling migration occurred between July 1 and September 22 and reached its peak between August 15–23. Individuals with earlier fledge dates migrated earlier. Plovers returned to the breeding grounds between February 20 and May 8 of their second year, with a peak occurring in late April and early May. Given that post-Hurricane Sandy habitats were suitable for plover nests and broods, ensuring protection of suitable habitats would also benefit fledglings that persist on Fire Island for more than a month before departure.

No description available.