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" Happy #WorldSeaTurtleDay ?! It is estimated that sea turtles have been living on Earth for ~110 million years. They are capable of holding their breath for up to five hours & diving to depths well below 1,000m! "
And I would add thea sea turtles are one of few natural predators (with the tuna) of the jellyfishes/medusas which they prevent the proliferation, one thing that humans would be unable to do. But sea turtles are also greatly threatened by the uncountable plastic particles floating in and into the oceans, direct consequences of the human pollution around the world...  (03-26-2020, 01:12 AM)Pckts Wrote: Global Documentary  (06-17-2020, 09:40 AM)Spalea Wrote: " Happy #WorldSeaTurtleDay ?! It is estimated that sea turtles have been living on Earth for ~110 million years. They are capable of holding their breath for up to five hours & diving to depths well below 1,000m! " Unfortunately that's happening everyday in the world....I've only seen a sea turtle once in the sea before when I was a kid....and somehow I think that would be the last time I would see one if this continues to happen. 
Sharks functionally extinct in many global reef systems
https://www.nature.com/articles/s41586-020-2519-y#https://www.nature.com/articles/s41586-020-2519-y (04-18-2014, 04:34 AM)peter Wrote: 1 - SHARKS  (08-05-2020, 04:27 PM)scilover Wrote:(04-18-2014, 04:34 AM)peter Wrote: 1 - SHARKS SCILOVER When you quote a post, do not respond in- but below the quote. If you respond in the quote, your response, like in this case, will only be visible when you click on the quote ('show more'). Contact Rishi for details. As to your response. Shark attacks near beaches in southeast Asia seldom make headlines. Same for Brazil, Chili and many other parts of the world. That, however, doesn't mean they don't happen. In some regions, attacks were (and are) so frequent beaches had to be closed permanently. Although the number of attacks every year is very limited, sharks are a very real threat in some parts of the world. Swimmers and surfers know and accept the risks. But the risk is close to zero, no? Well, it depends. I wouldn't say risk management is part of the equasion. Luck most definitely is. Example. Many years ago, I went to Greece. I took a boat to visit some of the islands. Santorini was one of them. I often swam on my own. Quite long distances. One day, the owner of the hotel said the sea was too rough for a swim. He wanted some work done and made me an offer I couldn't refuse. When I had finished the job, I climbed the rocks to watch the sea. Very close to the spot I always used as a start for my swim (a rock), I saw a real big shark surface. It was so close and visible I could see it was a female white shark. She stayed for some minutes. I knew she had seen me. The hotel owner didn't believe one word of the story. You drink too much, he said. Next day, when he asked me to use the dinghy to catch a few fish, I decided to take a ship to another island. There are more true stories, but people always say I drink too much. When they notice I only drink coffee, they say I need more sleep. Every now and then, a swimmer, diver or surfer diseappears near a popular beach somewhere in southern Europe. When I visit that region, people sometimes start on these incidents. I always say they drink too much. This is much appreciated by all, including the hotel owners. More often than not, it results in a free meal, a room with a view and extra service.
A tuna weighing 208 kg (459 pounds) got sold at 100,000 yen per kilogram, that is a whopping 20.84 million yen ($202,000), but that's 10% of its value in 2020, and Bloomberg commented: https://www.bloomberg.com/news/articles/...ar-auction
"The drop reflects a slump in demand as the coronavirus pandemic forced people to refrain from eating out and as authorities ask restaurants in some urban areas to close early." Credit: Kiyoshi Ota / Bloomberg
Oceanic shark and ray populations have collapsed by 70 percent over 50 years
On the high seas, far from any continent, sharks and rays were once abundant. Shortfin makos, the fastest sharks on the planet, chased after their prey at speeds of over 20 miles an hour. Scalloped hammerheads plied the waters, scanning the ocean expanse for food with their wide-set eyes and other specialized sensory organs. These animals traveled widely across open waters so vast and inaccessible that many fishermen, and even some biologists, found it hard to believe that overfishing would ever endanger them. “A decade ago,” recalls Nicholas Dulvy, co-chair of the International Union for Conservation of Nature’s Shark Specialist Group, “we would have extremely heated debates about listing an oceanic shark as threatened.” Now, a sweeping analysis of current and historic population numbers have created a clearer—and sobering—picture. Dulvy and co-author Nathan Pacoureau, both at Simon Fraser University in Canada, found that populations of 18 shark and ray species have declined by 70 percent since 1970, according to the study, published in the journal Nature this week. At this rate, many of the species might disappear entirely in a decade or two, the authors caution. (Read about the most fascinating shark discoveries of the last decade.) When the research team crunched the numbers for the oceanic whitetip shark, a species that was common back in 1970, we “just looked at them in stunned silence,” Dulvy says. The oceanic whitetip “had declined by 98 percent in the last 60 years. That pattern was consistent across all three oceans.” The International Union for Conservation of Nature now lists the species as critically endangered. Scalloped and great hammerhead sharks have met a similar fate. Though fisheries rarely target oceanic sharks, if they're caught, their meat, fins, gill plates, and liver oil is often sold. This is troubling news both for the sharks and ocean health, as these top predators play a crucial role in the food web, in part by keeping smaller predators in check, experts say. A purse seine net encircles fish on Iturup Island in Russia's Far East. This fishing technique often captures sharks as well. PHOTOGRAPH BY SERGEI KRASNOUKHOV, GETTY IMAGES Diving into the data For the study, Dulvy and Pacoureau collected all the data on those 18 species they could find across the globe, much of it buried in government reports or collecting dust on old hard drives. A growing public awareness of shark conservation has prompted fisheries management agencies to start collecting shark data, providing the team with an influx of brand-new information. The scientists ended up with 900 datasets spanning 1905 to 2018, each representing a species’ population changes over time within a particular region. With the help of international experts and computer modeling, the team extrapolated these data into best estimate of the global change in abundance. (Read more about sharks, lords of the sea.) They also took into account the development of open-ocean fishing techniques. Long lines studded with hundreds of hooks or enormous purse seine nets often accidentally ensnare sharks, and their use has doubled in the last half century, while the number of oceanic sharks caught in them has approximately tripled. “Combined with the increasing rarity of sharks, this means that the chance for an individual shark to get caught is now 18 times higher than it was in 1970,” says Dulvy. Dulvy adds that uncertainty is inevitable in his analysis, and that the authors have likely underestimated some of the species’ declines, particularly in areas where overfishing has occurred for many decades. Tropical fish hardest hit The biggest decrease occurred in shark and ray populations in the tropics, where offshore fisheries have expanded in recent decades. SHARKS 101Sharks can rouse fear and awe like no other creature in the sea. Find out about the world's biggest and fastest sharks, how sharks reproduce, and how some species are at risk of extinction. As larger sharks and rays become rare, fisheries are pivoting toward smaller species, says co-author Holly Kindsvater, a population biologist at Virginia Tech who has studied several species of devil rays, some populations of which may have fallen by 85 percent in the past 15 years. Though people do eat their meat, their gill plates have recently become more popular in Chinese medicine. This shift shows how fishermen can pivot to other species when their original prey becomes scarce, she says. (Read how reef sharks are also in big trouble worldwide.) “I don’t think there are many boats on the high seas exclusively targeting sharks and rays. But if you’ve started out fishing for tuna, and you’ve overfished them, you’ll start catching other things, and you’ll find a way to sell those, as well.” Fishing for solutions The impact of overfishing, accidental or otherwise, on sharks should motivate governments to impose more regulations, with the goal of making fisheries sustainable, Dulvy says. It's also important, he adds, to limit the international trade of threatened shark and ray species. But there’s a long way to go. A proposed ban on fishing of endangered shortfin makos in the North Atlantic was recently blocked by the European Union and the United States, in part because the bulk of the catch is by Spain, says Dulvy. “Sharks are kind of the last unregulated area,” he says, “which I think is why there is a bit of resistance to managing them.” Such a ban has been shown to work for other species, says David Sims, a biologist at the U.K.’s University of Southampton who was not involved in this study. Sims has published research showing hopeful signs of recovery for great white sharks and porbeagles in the northwestern Atlantic, both of which are protected from fishing. (Learn about six sharks you’ve probably never heard of.) Other solutions include creating marine reserves or setting aside no-fishing zones in shark-rich hot spots, Sims says. Jessica Cramp, founder of the marine research and conservation organization Sharks Pacific and a National Geographic Explorer, agrees. She has helped establish several protected areas and a shark sanctuary in the Cook Islands to benefit migratory species, including sharks. “These may offer refuge for species like the oceanic whitetip and silky shark,” she says, ”which this study has confirmed are in big trouble.”
Pteropoda or pteropods of the species Creseis Acicula (in the family of Thecosomes or sea butterflies (Thecosomata), a sub-category of sea snails in the clade of Heterobranchia) have been discovered in beaches across the U.A.E.: https://www.khaleejtimes.com/news/uae-st...ay-experts
Measuring 7.15–13.2 mm (0.28–0.52 inches), their bodies are protected by a pointed needle-like shell. These organisms are not considered toxic and do not pose a threat to the safety of beachgoers, the Dubai Municipality had said. However, they can cause discomfort as they can stick to the body and they usually die on the dry sand after the tides sweep them to the shore. In Umm Al-Quwain, the marine organisms spotted by beachgoers were non-toxic molluscs. These species are small, transparent, and pointed. Marine specialists say the family of molluscs are most likely found on upper layer of the world’s oceans and the reason for the sudden appearance is due to increase in the water temperature. These creatures can be seen on the shores around this time of year, as well as when the tides and currents follow the full moon. These factors cause these creatures to enter shallow waters where they subsequently die and wash up on the beaches. These organisms are part of the Diel vertical migration (DVM) cycle, the synchronised movement of zooplankton and fish up and down in the water column over a daily cycle. “When the currents push these organisms into the shallows, they can’t descend, leading to their death and them washing up on the beaches,” James explained. A picture of a pteropod provided by S. M. Ayaz Zakir of Khaleej Times on the 2nd of June:  *This image is copyright of its original author Quote:Elephant shark in Olhão, Algarve, Portugal at the beginning of the 20th century |
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