Abstract
Wildlife health assessments evaluate the health of individual animals that make up a population.1 These individuals serve as representatives of their species and aid in guiding conservation efforts, particularly for threatened and endangered species,2 such as scalloped hammerhead sharks (Sphyrna lewini). Scalloped hammerhead sharks have experienced significant population decline and are currently classified as critically endangered by the IUCN.3-5 This species is particularly susceptible to overexploitation due to its unique anatomic and behavioral traits.3,5,6 Though management strategies focused on adults are difficult due to their natural schooling behavior and migratory patterns,7 those focused on juvenile animals may provide better guidance in population status and conservation. This study aimed to begin establishing baseline health parameters for juvenile scalloped hammerheads in San Cristóbal, Galápagos, Ecuador.
Health assessments conducted consisted of physical examination, morphometric measurements, and blood collection from juvenile scalloped hammerheads. Animals were collected via beach seine and held in dorsal recumbency under manual restraint for sample collection. Samples were analyzed using a commercial chemistry analyzer and the data examined using Excel software.
Individual health assessments of sentinel species can serve to establish baseline parameters for comparison to future time points. These assessments allow for evaluation of the impacts of conservation efforts and environmental disturbances on populations, highlighting the intimate link between health and conservation.1 Scalloped hammerhead sharks are one such species, with pups often serving as apex predators in estuaries and nursery areas.6 Unlike adults, pups are non-migratory and spend prolonged time in a single location before venturing to the open ocean.6 Thus, management of this age group may prove to be more feasible.
As environments continue to evolve, the increase in disease potential and environmental change may negatively impact populations.8 Analyses of individuals in a population are needed to guide long-term management decisions,1 with veterinarians possessing the unique ability to close the gap between individual health and global conservation.8
Acknowledgments
The authors would like to thank the Galápagos Science Center, the San Cristóbal boat crews, and other researchers for dedicated assistance. We would also like to thank Idexx Laboratories for generously donating chemistry cartridges. All work was conducted under NC State University IACUC number 23-157.
*Presenting author
+Student presenter
Literature Cited
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