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Background: Despite considerable research on nest site selection of diamondback terrapins and the risks that coastal roads pose to populations of this obligate estuarine turtle, there are gaps in our understanding of movements and habitat use by female terrapins during the nesting season. In particular, movements within salt marshes, shallow water habitats, and nest site-adjacent developed habitats remain relatively understudied. To investigate habitat use and risk exposure of this semiaquatic species, we employed an automated radio telemetry system featuring 31 passive receivers. In 2021, concurrent with annual nest surveys, we tracked 60 telemetered female terrapins near a nesting area in southern New Jersey subject to impacts from road mortality. We triangulated terrapin locations based on the relationship between radio signal strength at each receiver and distance, generated utilization distributions using kernel density estimation, and classified habitat using multispectral imagery. Results: We detected differences in habitat use versus relative availability within general (95% KDEs) and core (50% KDEs) use areas at a population level. Core use areas suggested more frequent use of salt pools, marsh, and upland habitats and less frequent use of developed and wide tidal creek habitats than expected based on availability alone. To further characterize variability in habitat use, we compared selectivity between terrapins grouped by proximity of their capture location to a road. Terrapins nesting closer to the road showed relatively more frequent usage of developed habitats and less frequent usage of narrow creeks and regularly flooded marsh throughout the nesting season. Conclusions: Patterns of habitat selection across all terrapins underscore the importance of shallow water habitats such as salt pools near nesting areas. Individuals tended to spend more time in habitat types close to their nesting locations, such that terrapins initially captured near roads spent more time in high-risk developed areas throughout the study period. Road mortality risk may not be homogenous within this nesting population, which may be a critical consideration for demographic modeling. This study expands our understanding of terrapin movements while demonstrating the effectiveness of a novel radio telemetry approach, and contributes to conservation planning in a rapidly changing salt marsh landscape. [ABSTRACT FROM AUTHOR]

In addition to aerobic endurance and anaerobic capacity, high power-to-weight ratio (PWR) is important for cycling performance. Cyclists often try to lose weight before race season to improve body composition and optimize PWR. Research has demonstrated body fat-reducing benefits of exercise after fasting overnight. We hypothesized that fasted-state exercise in calorie-restricted trained cyclists would not result in performance decrements and that their PWR would improve significantly. We also hypothesized that substrate use during fasted-state submaximal endurance cycling would shift to greater reliance on fat. Ten trained, competitive cyclists completed a protocol consisting of baseline testing, 3 weeks of caloric restriction (OR), and post-OR testing. The testing sessions measured pre- and post-CR values for resting metabolic rate (RMR), body composition, [??][O.sub.2]max, PWR and power-to-lean weight ratio (PLWR), and power output, as well as 2-hour submaximal cycling performance, rating of perceived exertion (RPE), and respiratory exchange ratio (RER). There were no significant differences between baseline and post-OR for submaximal trial RER, power output, [??][O.sub.2], RMR, [??][O.sub.2]max, or workload at [??][O.sub.2]max. However, RPE was significantly lower, and PWR was significantly higher post-OR, whereas RER did not change. The cyclists' PWR and body composition improved significantly, and their overall weight, fat weight, and body fat percentage decreased. Lean mass was maintained. The cyclists' RPE decreased significantly during 2 hours of submaximal cycling post-OR, and there was no decrement in submaximal or maximal cycling performance after 3 weeks of OR combined with overnight fasting. Caloric restriction (up to 40% for 3 weeks) and exercising after fasting overnight can improve a cyclist's PWR without compromising endurance cycling performance. KEY WORDS diet, substrate use, power-to-weight ratio