recreational rod-and-reel fishery, we worked directly with recreational fishing captains to investigate the PRM of blacknose sharks, Carcharhinus acronotus. However, the accuracy of PRM rates is dependent on our ability to evaluate mortality under realistic fishing practices and conditions. The post-release mortality (PRM) rate of sharks can be an important factor in estimating overall mortality in stock assessments. Overall, we provide valuable information for evidence-based species-specific conservation and management strategies for coastal sharks. Distances to the nearest estuary, headland, and island, as well as water temperature and wave height, were significant predictors of shark occurrence however, this varied among species. Generalised additive models were used to identify environmental drivers for detection probability of white, bull, greynurse, and whaler sharks. Bull sharks (Carcharhinus leucas), leopard sharks (Stegostoma tigrinum) and hammerhead species (Sphyrna spp.) recorded 29, eight and three individuals, respectively.
There were 34 individuals observed for both white sharks (Carcharodon carcharias) and critically endangered greynurse sharks (Carcharias taurus). Whaler sharks (Carcharhinus spp.) had the highest number of observations (n = 158) recorded.
Overall, there were 347 chondrichthyans recorded, comprising 281 (81.0%) sharks, with observations occurring in <1% of flights. We quantified sharks in 36,384 drone flights across 42 ocean beaches from 2017 to 2021. We used long-term and large-scale drone surveying techniques to test hypotheses about the relative abundance and occurrence of sharks off ocean beaches of New South Wales, Australia. There is still limited information about the diversity, distribution, and abundance of sharks in and around the surf zones of ocean beaches.
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