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After 400 Million Years, Coelacanth at Risk of Extinction.

After 400 Million Years, Coelacanth at Risk of Extinction.

Tuna face extinction within 50 years as rising popularity of sushi is blamed on declining numbers.

Fish and other sea creatures will have to travel large distances to survive climate change, international marine scientists have warned. Sea life, particularly in the Indian Ocean, the Western and Eastern Pacific and the subarctic oceans will face growing pressures to adapt or relocate to escape extinction, according to a new study by an international team of scientists published in the journal Science.

Marine scientists from the University of Queensland, WCS (Wildlife Conservation Society) and other groups have developed a methodology to assess fish stocks that combines new data with archeological and historical records - some dating back to the 8th Century AD. In a study conducted in along the coast of Kenya, the researchers reconstructed species' occurrences by combining modern underwater transect surveys and catch assessments with historical records that included observations from 18th century naturalists and data from archaeological sites including ancient middens dating back more than a thousand years.

Tropical ecosystems sustain higher biodiversity and face faster species extinction. However, baseline information of these areas is either inadequate or scattered due to various reasons. The 2,360 km long coast of North West India (NWI), is a heavily industrialized and urbanized zone. This coast with unique biogeographical and climatic features with two notified marine protected areas also supports rich biodiversity. This review was motivated by a need to construct a synoptic view on marine benthic ecology and functioning by consolidating available information of macrobenthos. Two thousand seventy-eight macrobenthic taxa belonging to 14 phyla were compiled from 147 references and were composed mostly by Polychaeta (n = 617), Gastropoda (n = 602), and Bivalvia (n = 216). Habitat wise, intertidal and subtidal zones were more intensely studied and contributed most to the diversity records. Sediment texture and salinity were the major drivers of macrobenthic community structure in the subtidal areas and estuaries, respectively. In the intertidal zones, zonation patterns related to the tidal levels and time of exposure were distinct with the high water zones being sparsely populated and lower intertidal zones sustaining higher species and functional diversities. All zones of NWI coast were distinctly impacted to various extent by anthropogenic activities affecting the resident macrobenthos. Decline in species richness and species substitution due to pollution were reported in urbanized zones. Non-monsoonal months favored a more conducive environment for the macrobenthic diversity and functionality. Hypoxia tolerant polychaete species mainly belonging to Spionidae and Cossuridae dominated during the low oxygen conditions of upwelling and OMZ zones of NWI. Inadequate identification and inconsistency of sampling methods were major deterrents for concluding trends of distributions. Suggestions for future macrobenthic research include focusing on lesser studied groups and are

Islands are biodiversity hotspots yet, paradoxically, are also extinction hotspots.

Forecasting the influence of climate change on coral biodiversity and reef functioning is important for informing policy decisions. Dominance shifts, tropicalization and local extinctions are common responses of climate change, but uncertainty surrounds the reliability of predicted coral community transformations. Here, we use species distribution models (SDMs) to assess changes in suitable coral habitat and associated patterns in biodiversity across Western Australia (WA) under present-day and future climate scenarios (RCP 2.6 and RCP 8.5).

The Indian Ocean humpback dolphin (Sousa plumbea) is "endangered" with likely less than 500 animals remaining in South African waters. Established in 2016, the SouSA Consortium is a formalised network of scientists and conservationists to combine knowledge and research efforts, and make coordinated decisions with the aim of conserving the species. The first collaborative project collated available photo-identification data in an attempt to refine a national population estimate and investigate movements between research sites. This work was able to identify 250 uniquely marked individuals, with the population divided into the south-coast (Agulhas bioregion) and east-coast (Natal bioregion) populations. Environmental factors almost certainly play a role in the declining numbers of the species in South African waters. However, individual threats and solutions are challenging to identify as the South African marine environment is undergoing significant natural and anthropogenic changes with major shifts in the distribution and numbers of some prey, competitor and predator species. Therefore, we believe that a continued investigation of potential contributing factors and their interaction will take too long, inevitably resulting in another case of documenting extinction. With this in mind, we present the results of a SWOT (Strengths, Weaknesses, Opportunities, and Threats) analysis in an effort to help us identify the next steps to take toward the conservation of humpback dolphins in South African waters. We unanimously conclude that no single cause for the rapid decline of humpback dolphins in South African waters can be identified, and that the cumulative effects of multiple stressors, which are difficult to pinpoint and mitigate, are impacting population numbers. While highlighting the need for continued research, we suggest a shift toward more action-focused conservation efforts, the first concrete steps being the development of a Conservation Management Plan wit

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

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

Tropical regions experience a diverse range of dense clouds, posing challenges for the daily reconstruction of chlorophyll-a concentration data. This underscores the pressing need for a practical method to reconstruct daily-scale chlorophyll-a concentrations in such regions. While traditional data reconstruction methods focus on single variables and rely on specific factors to infer missing data at specific locations, these single-variable methods may falter when applied to tropical oceans due to the scarcity of available data. Fortunately, all oceanographic variables undergo similar atmospheric and marine dynamic processes, creating internal relationships between them. This allows for the reconstruction of missing data through correlations between variables. Thus, this study introduces a multivariate reconstruction approach using the extended data interpolating empirical orthogonal function (ExDINEOF) method to reconstruct missing daily-scale chlorophyll-a concentration data. The ExDINEOF method considers the simultaneous relationships among multiple variables for data reconstruction in tropical oceans. To verify the method's robustness, missing data were reconstructed during the formation and passage of severe tropical cyclone Hudhud through the Bay of Bengal. The results demonstrate that ExDINEOF outperforms traditional data reconstruction methods, exhibiting favorable spatial distribution and enhanced accuracy within the dynamic tropical marine environment. Furthermore, an assessment of marine physical environmental factors associated with chlorophyll-a concentration data provides additional evidence for the ExDINEOF method's accuracy. Notably, the ExDINEOF method offers comprehensive spatial distribution aligned with underlying physical mechanisms governing phytoplankton distribution patterns, detailed phytoplankton growth, bloom, extinction variations in time series, satisfactory accuracy, and comprehensive local-level details.

Why the World's Biggest Sharks Love Mafia Island.

The move could help protect this millions-of-years-old species.

The move could help protect this millions-of-years-old species.

Older than dinosaurs: last South African coelacanths threatened by oil exploration.

Shark Attacks in WA Inspired Surfing Scientists

Mozambique sharks, manta rays population decline spurs conservation efforts.