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Categories: Biology: Marine, Ecology: Sea Life
Published Artificial reefs help preserve coral reefs by shifting divers away from the natural ones, according to new long-term study of one in Eilat



Divers are essentially tourists who love coral reefs and invest a lot of time and effort to watch them. Unfortunately, divers also cause damage to corals, often unintentionally, through disturbing and resuspending sand, touching them, hitting them with their equipment, and scaring fish away. Artificial reefs have been proposed as a means of diverting diving pressure from the natural reef to alternative sites, thus preserving both dive tourism and the coral reef.
Published Nature's checkup: Surveying biodiversity with environmental DNA sequencing



A thousand kilometers south of Tokyo, far into the largest ocean on Earth, lies a chain of small, volcanic islands -- the Ogasawara Islands. Nature has been able to develop on its own terms here, far from both humans and the warm Kuroshio current, which acts like a shuttle, moving marine species from Taiwan, over the Ryukyu Islands, and up the Pacific coast of mainland Japan. With upwards of 70 % of trees and many animal species being endemic to the archipelago, the islands have been dubbed 'the Galapagos of the East', as they are valuable as both a biodiversity hotspot and a cradle of scientific discovery.
Published Decline in microbial genetic richness in the western Arctic Ocean



Researchers analyzed archival samples of bacteria and archaea populations taken from the Beaufort Sea, bordering northwest Canada and Alaska. The samples were collected between 2004 and 2012, a period that included two years -- 2007 and 2012 -- in which the sea ice coverage was historically low. The researchers looked at samples taken from three levels of water: the summer mixed layer, the upper Arctic water below it and the Pacific-origin water at the deepest level. The study examined the microbes' genetic composition using bioinformatics and statistical analysis across the nine-year time span. Using this data, the researchers were able to see how changing environmental conditions were influencing the organisms' structure and function.
Published Viruses that can help 'dial up' carbon capture in the sea



Armed with a catalog of hundreds of thousands of DNA and RNA virus species in the world's oceans, scientists are now zeroing in on the viruses most likely to combat climate change by helping trap carbon dioxide in seawater or, using similar techniques, different viruses that may prevent methane's escape from thawing Arctic soil.
Published Why two prehistoric sharks found in Ohio got new names



Until recently, Orthacanthus gracilis could have been considered the 'John Smith' of prehistoric shark names, given how common it was. Three different species of sharks from the late Paleozoic Era -- about 310 million years ago -- were mistakenly given that same name, causing lots of grief to paleontologists who studied and wrote about the sharks through the years and had trouble keeping them apart. But now a professor has finished the arduous task of renaming two of the three sharks -- and in the process rediscovered a wealth of fossil fishes that had been stored at a museum for years but had been largely forgotten.
Published Giant Antarctic sea spiders reproductive mystery solved



Instead of carrying the babies until they hatched, as in most species of sea spiders, one parent (likely the father) spent two days attaching the eggs to the rocky bottom where they developed for several months before hatching as tiny larvae.
Published Beyond peak season: Bacteria in the Arctic seabed are active all year round



Researchers studied the composition and function of bacteria in the seabed off Svalbard, during alternating periods of polar night and midnight sun. To do this, they specially developed a sampling device, the Ellrott grab. In contrast with bacterial communities in the overlying water, the sediment bacteria hardly change with the seasons. This is probably due to the fact that in the seabed some hard-to-digest foods are available all year round.
Published Diving deeper into our oceans: Underwater drones open new doors for global coral reef research



Scientists take innovation in coral e-DNA monitoring to the next level.
Published The role of jellies as a food source in the Arctic winter



The Arctic is changing rapidly due to climate change. It is not only affected by increasing surface temperatures, but also by warm water from the Atlantic, which is flowing in more and more -- changing the structures and functions of the ecosystem as it also leads to species from warmer regions, such as sea jellies (also known as jellyfish) arriving in the Arctic. Using DNA metabarcoding, researchers have now been able to demonstrate that these jellyfish serve as food for amphipods on Svalbard during the polar night and thus play a greater role in Arctic food webs than previously assumed.
Published Cold-water coral traps itself on mountains in the deep sea



Corals searching for food in the cold and dark waters of the deep sea are building higher and higher mountains to get closer to the source of their food. But in doing so, they may find themselves trapped when the climate changes.
Published If we can't untangle this mess, Norway's blue industry will never be green



For the first time, researchers have investigated how ropes and fishing lines are handled by the Norwegian commercial fishing industry. The fishing fleet loses almost 400 tons of rope in Norwegian waters every year.
Published Polar bears unlikely to adapt to longer summers



More time stranded on land means greater risk of starvation for polar bears, a new study indicates. During three summer weeks, 20 polar bears closely observed by scientists tried different strategies to maintain energy reserves, including resting, scavenging and foraging. Yet nearly all of them lost weight rapidly: on average around 1 kilogram, or 2.2 pounds, per day. Some have speculated that polar bears might adapt to the longer ice-free seasons due to climate warming by acting like their grizzly bear relatives and either rest or eat terrestrial food. The polar bears in this study tried versions of both strategies -- with little success.
Published Satellites unveil the size and nature of the world's coral reefs



New research has shown there is more coral reef area across the globe than previously thought, with detailed satellite mapping helping to conserve these vital ecosystems.
Published Compounds released by bleaching reefs promote bacteria, potentially stressing coral further



New research revealed that when coral bleaching occurs, corals release unique organic compounds into the surrounding water that not only promote bacterial growth overall, but select for opportunistic bacteria that may further stress reefs.
Published How ancient sea creatures can inform soft robotics



Fossils of a marine animal that lived 500 million years ago, combined with computer simulations, informed the design of a new soft robot.
Published Surprisingly vibrant color of 12-million-year-old snail shells



Snail shells are often colorful and strikingly patterned. This is due to pigments that are produced in special cells of the snail and stored in the shell in varying concentrations. Fossil shells, on the other hand, are usually pale and inconspicuous because the pigments are very sensitive and have already decomposed. Residues of ancient color patterns are therefore very rare. This makes a new discovery all the more astonishing: researchers found pigments in twelve-million-year-old fossilized snail shells.
Published Surprising behavior in one of the least studied mammals in the world



Beaked whales are among the least studied mammals in the world. Now, a new study reveals surprising information about the Baird's beaked whale species.
Published How kelp forests persisted through the large 2014-2016 Pacific marine heatwave



New research reveals that denser, and more sheltered, kelp forests can withstand serious stressors amid warming ocean temperatures.
Published Remarkable cellular architecture and phylogenetic position of the mysterious arm-swinging protist meteora sporadica



Researchers studied in detail the strange protist Meteora sporadica, which swings its two lateral arms back and forth. The results of the study indicated that M. sporadica has a complex cytoskeleton that is closely related to Hemimastigophora, a group of organisms considered to be one of the deepest branches of eukaryotes.
Published Number of shark bites consistent with recent trends, with small spike in fatalities



There was an increase in the number of unprovoked shark attacks worldwide and an uptick in fatalities in 2023 compared to the previous year. A scientific database of global shark attacks, confirmed 69 unprovoked bites in 2023. Although this is higher than the most recent five-year average of 63 attacks, the data remain consistent with long-term trends.