The UCF Marine Turtle Research Group (MTRG) has monitored sea turtle nesting for over 40 years along the Brevard County, Florida coastline, yielding one of the world's longest and continuous sea turtle reproductive datasets. These data offer demographic insights crucial for assessing conservation success and species population recovery. There is need for analyses to better understand long-term trends in hatchling emergence success and emergence phenology, as worsening conditions of climate change may have negative implications for reproductive output, population growth, recovery, and hatchling dispersal among sea turtle rookeries. Here I compare the long-term reproductive output trends of loggerhead (Caretta caretta), green (Chelonia mydas), and leatherback (Dermochelys coriacea) sea turtles from the densely nested Archie Carr National Wildlife Refuge (ACNWR), over a turtle-generation time frame (20-40 years). With potential phenological shifts occurring due to climate change, hatchling emergence success and timing may be at risk due to changes in exposure to seasonal and temporal conditions over time. My two primary objectives are: 1) to assess changes over time in hatchling reproductive output in all three species in relation to abiotic and biotic influences, and 2) to determine if there have been changes over time in hatchling emergence phenology across the three species. Long-term emergence success has remained stable, though species-specific differences exist. Water disturbances and raccoons had the most severe impacts, significantly increasing nest failure in greens and loggerheads, while leatherbacks remained less affected. Median emergence dates are shifting later for loggerheads and green turtles, while shifting earlier for leatherbacks. The emergence season is lengthening for loggerheads and leatherbacks but shortening for green turtles. These findings provide essential baselines for long-term emergence success and hatchling emergence phenology, helping to assess species trends and understand how sea turtles may be adapting to the challenges of climate change.
Jeena Prasertlum
Dr. Kate Mansfield, Advisor
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