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Marine megafauna species are affected by a wide range of anthropogenic threats. To evaluate the risk of such threats, species’ vulnerability to each threat must first be determined. We build on the existing threats classification scheme and ranking system of the International Union for Conservation of Nature (IUCN) Red List of Threatened Species by assessing the vulnerability of 256 marine megafauna species to 23 at‐sea threat...
How to estimate age of old bottlenose dolphins (Tursiops truncatus); by tooth or pectoral flipper?OA Marine
Multiple techniques have been used for estimating age in bottlenose dolphins ( Tursiops truncatus ). The longest established technique is via counts of growth later groups (GLGs) in the longitudinal section of an extracted mandibular tooth. Previous studies to validate GLGs have primarily used younger dolphins (less than 16yrs old) due to the limited number of known age older animals. This study assessed the accuracy of age es...
Scleractinian corals are increasingly subjected to local stressors combined with global changes. In subtropical areas, corals exhibit metabolic plasticity and resilience in response to variability and extremes in local temperature, salinity, and light; however, the physiological mechanisms by which corals acclimate or adapt to these changing conditions remain disputed. We assessed the physiological status of the coral Platygyr...
Approximately one-quarter of the CO2 emitted to the atmosphere annually from human activities is absorbed by the ocean, resulting in a reduction of seawater pH and shifts in seawater carbonate chemistry. This multi-decadal process, termed “anthropogenic ocean acidification” (OA), has been shown to have detrimental impacts on marine ecosystems. Recent years have seen a globally coordinated effort to measure the changes in seawa...
This study examines resource use (diet, habitat use, and trophic level) within and among demographic groups (males, females, and juveniles) of bottlenose dolphins ( Tursiops truncatus ). We analyzed the δ 13 C and δ 15 N values of 15 prey species constituting 84% of the species found in stomach contents. We used these data to establish a trophic enrichment factor ( TEF ) to inform dietary analysis using a Bayesian isotope mixi...
Policy documents advocate that managers should keep their options open while planning to protect coastal ecosystems from climate‐change impacts. However, the actual costs and benefits of maintaining flexibility remain largely unexplored, and alternative approaches for decision making under uncertainty may lead to better joint outcomes for conservation and other societal goals. For example, keeping options open for coastal ecos...
Retrospective analysis of bottlenose dolphin foraging: A legacy of anthropogenic ecosystem disturbanceNARA Subscribed
We used stable isotope analysis to investigate the foraging ecology of coastal bottlenose dolphins ( Tursiops truncatus ) in relation to a series of anthropogenic disturbances. We first demonstrated that stable isotopes are a faithful indicator of habitat use by comparing muscle isotope values to behavioral foraging data from the same individuals. δ 13 C values increased, while δ 34 S and δ 15 N values decreased with the perce...
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