UK brands act to cut catch of 'near-threatened' yellowfin tuna - @karenmcveigh1 @guard... - 0 views
Via @Seasaver - Orcas found to kill blue whales, the largest animals on Earth, for firs... - 0 views
Sex and size influence the spatiotemporal distribution of white sharks, with implicatio... - 0 views
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Human activities in the oceans increase the extinction risk of marine megafauna. Interventions require an understanding of movement patterns and the spatiotemporal overlap with threats. We analysed the movement patterns of 33 white sharks (Carcharodon carcharias) satellite-tagged in South Africa between 2012 and 2014 to investigate the influence of size, sex and season on movement patterns and the spatial and temporal overlap with longline and gillnet fisheries and marine protected areas (MPAs). We used a hidden Markov model to identify 'resident' and 'transient' movement states and investigate the effect of covariates on the transition probabilities between states. A model with sex, total length and season had the most support. Tagged sharks were more likely to be in a resident state near the coast and a transient state away from the coast, while the probability of finding a shark in the transient state increased with size. White sharks moved across vast areas of the southwest Indian Ocean, emphasising the need for a regional management plan. White sharks overlapped with longline and gillnet fisheries within 25% of South Africa's Exclusive Economic Zone and spent 15% of their time exposed to these fisheries during the study period. The demersal shark longline fishery had the highest relative spatial and temporal overlap, followed by the pelagic longline fishery and the KwaZulu-Natal (KZN) shark nets and drumlines. However, the KZN shark nets and drumlines reported the highest white shark catches, emphasising the need to combine shark movement and fishing effort with reliable catch records to assess risks to shark populations accurately. White shark exposure to shark nets and drumlines, by movement state, sex and maturity status, corresponded with the catch composition of the fishery, providing support for a meaningful exposure risk estimate. White sharks spent significantly more time in MPAs than expected by chance, likely due to increased prey abundance
They squeaked as they died: I tried to help those baby pilot whales - but nothing could... - 0 views
Dozens of pilot whales beached in mass stranding east of Albany in WA - @joshgnosis @gu... - 0 views
Tasmanian crews start hauling carcasses of stranded whales out to sea - @AAPNewswire vi... - 0 views
More than a dozen sperm whales die in mass stranding on King Island - @AAPNewswire @gua... - 0 views
Hundreds of whales stranded on Tasmania's west coast in state's second event this week ... - 0 views
Rescuers rush to save hundreds of pilot whales stranded on Tasmanian beach - @donnadlu ... - 0 views
Nearly 200 stranded pilot whales die on Tasmanian beach - @AAPNewswire @guardianeco - 0 views
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