Some observations on the abundance and biomass of Elasmobranch fishes captured over stratified bottom trawl surveys from the special environmental protection area of Datça-Bozburun (Türkiye)
Elasmobranchs from environmental protection area
DOI:
https://doi.org/10.5281/zenodo.15763732Keywords:
Biodiversity, conservation, elasmobranchs, marine protected area, overfishing, trawl surveysAbstract
This study investigates the abundance and biomass of elasmobranch fishes (sharks and rays) within and outside the Datça-Bozburun Special Environmental Protection Area (SEPA) in Turkey, using data from stratified bottom trawl surveys conducted in 2009-2010. Elasmobranchs, a vital group in marine ecosystems, are increasingly at risk of extinction due to various anthropogenic threats, particularly overfishing. This research addresses the decline of elasmobranch populations in the Turkish Seas, where they have become increasingly scarce. The methodology involved six trawl hauls at depths greater than 100m, covering a total area of 1.20 km2, and the standardized catch per unit trawling area was calculated to estimate abundance and biomass. The Shannon-Wiener diversity index was used to assess species diversity within and outside the SEPA. Key findings reveal differences in elasmobranch communities inside and outside the protected area. Implications of the study emphasize the importance of marine protected areas for elasmobranch conservation in the face of overfishing and habitat degradation. The results of this study can be used in future assessments and fisheries management strategies.
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