Abstract
While elasmobranchs are considered as one of the most endangered group of animals worldwide,1 the Canary Islands represents a stronghold for a wide variety of threatened shark and ray species.2 However, the increase in elasmobranch deaths in recent years in the Canarian archipelago, a region where a high level of tourism and human activities converge in areas close to the habitat of these animals, raises concerns about the underlying causes. Among anthropogenic causes of death, fishing interactions are the greatest threat for these species.3 The main pathologies resulting from fishing interactions are different forms of trauma, including penetrating and blunt force trauma and different types of lesions caused by hooks, mainly in the oral cavity, digestive tract, gills and skin.4 This study describes the diagnostic imaging findings obtained through computed tomography scans, as well as their correlation with macroscopic lesions and histopathological analysis, in three cases of elasmobranchs with anthropogenic causes of death due to interaction with fishing activities and one case of death due to natural causes resulting from dystocia. There are two cases of penetrating wounds compatible with pike pole, harpoon or similar in one angelshark (Squatina squatina) and one spiny butterfly ray (Gymnura altavela), a case of hook injury in one smooth hammerhead (Sphyrna zygaena) and one case of death associated with dystocia in a female angelshark. The application of advanced imaging techniques enables a more comprehensive approach to elucidating the causes of mortality in elasmobranchs.
Acknowledgements
The authors wish to thank Loro Parque Fundación, the Poema del Mar Aquarium and Red Vigía Canarias (Canary Islands Wildlife Health Surveillance Network) for supporting this work.
*Presenting author
Literature Cited
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