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Satellite telemetry is a valuable tool for examining long-term, large scale movements of highly migratory species. Tracking data can be used by resource managers to protect habitat and ensure recovery of threatened and endangered species. Few tracking studies have focused on habitat use patterns of juvenile, neritic stage turtles. Satellite tracking surveys were conducted to assess juvenile green turtle movements in the northwestern Gulf of Mexico during 2006-2010. Fifteen turtles were equipped with platform terminal transmitters (PTT; 3 rehabilitated, 12 wild). Mean track duration was 129 days (range: 16-344 days). A hierarchical switching state-space model (hSSM) was applied to extrapolate population level foraging/resident versus migratory movements. All turtles displayed residency in Texas bays during summer months (March-November) while five individuals exhibited seasonal migrations into Mexican waters following passage of strong cold fronts in December and January. Winter (e.g., Mexico) versus summer (e.g., Texas) core areas were not significantly different. Winter 95% contours were significantly larger than summer (summer: 125.4 ± 47.5 km 2 , n = 15; winter: 274.4 ± 252.9 km 2 , n = 5). Space-time hot spot analysis provided a new and unique approach for conducting spatiotemporal cluster analysis, and was applied to migratory turtles to determine monthly changes in distribution and habitat associations. Changes in hot spots over time were detected within the lower regions of the Laguna Madre with punctuated intervals of hot spot activity. Upper regions of the Laguna Madre were identified as new hot spots in the later part of the year (e.g., Fall/Winter). Within core areas in Texas, seagrasses comprised an average density of 32.4% while 87.5% of the total available seagrass habitat occurred within the 95% KDE contour. Based on PTT and historic tide station surface water temperatures, all turtles tracked over winter migrations and residencies (n = 5) remained within waters > 15 • C, suggesting a threshold temperature at which migration behavior may be initiated. Continued recovery of threatened and endangered sea turtle populations depends on a comprehensive examination of patterns in habitat use. These data suggest cooperation between the United States and Mexico is needed to protect critical habitat and enhance recovery of this species.

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Coastal saltmarshes are a unique habitat at the interface of tidal coastal waters and freshwater inflow providing foraging and nursery habitat for a dynamic nekton community. Saltmarshes are particularly exposed to natural disturbances such as tropical storms, which can cause shifts in water chemistry and nekton community composition. Hurricane Harvey resulted in widespread flooding and record freshwater inflow into Galveston Bay in late August 2017. This study examined the influence of the hurricane on nekton community composition of two saltmarshes in Galveston Bay, TX. Nekton were monitored from February to December 2017 using minnow seines and Breder traps. Reduced abundance and increased diversity, despite the overall reduced number of taxa of the nekton community, were documented following the hurricane. Exacerbating these differences were reduced catches of the numerically dominant daggerblade grass shrimp, Palaemonetes pugio, following the event. For some key dominant species, a significant reduction in length was measured between pre-and post-disturbance; therefore, it is likely that new recruits, rather than the return of displaced adults, drove the community recovery. A complete recovery to a pre-disturbance state will likely require at least a full year due to seasonal recruitment patterns of many of the saltmarsh nekton species. Short-term but large-scale natural disturbances can significantly impact saltmarsh nekton communities, but because of their dynamic nature, they are generally resilient.