Science of an underdog: the improbable comeback of spring-run Chinook salmon in the San Joaquin River: ““You can’t design a worse evolutionary strategy for the Anthropocene” There are many variants on this quote, and we’ve heard them often in reference to the status of native fishes in California and other freshwater organisms worldwide. Indeed, the statement rings true for Pacific salmon, but especially spring-run Chinook salmon (Oncorhynchus tshawytscha) in California. And although the current situation certainly looks bleak overall for endangered salmon (Moyle et al. 2017), there are signs in a few corners that the arrow may finally be pointing up. For the last four years, our team at UC Davis has been conducting scientific studies on reintroduced spring-run Chinook salmon in the San Joaquin River and we wanted to take a minute to share some of what we’ve learned. Plus, everyone loves a good comeback story right? … ” Continue reading at the California Water Blog here: Science of an underdog: the improbable comeback of spring-run Chinook salmon in the San Joaquin River
Reconnected and it feels so good? Symposium on estuarine connectivity: “Many environments are becoming increasingly fragmented by human development, but addressing this issue is more complicated than simply reconnecting all the habitat pieces. Ecological connectivity, or the degree to which living things and ecological processes can move through an ecosystem, may be thought of as a “Goldilocks” issue: too much or too little can both have negative consequences. The struggle to balance on the razor’s edge of healthy connectivity was highlighted at the recent Estuarine Connectivity Symposium held at UC Davis on February 18, 2020. The research presented made it clear that fostering resilient ecosystems requires careful thought about restoring and maintaining connectivity. … ” Read more from FishBio here: Reconnected and it feels so good? Symposium on estuarine connectivity
California floater mussels take fish for an epic joyride: “Ecologist Jonathan Young steered his rowboat alongside a rectangular container that was floating between two bright orange buoys. He reached under a plastic mesh covering and pulled out a large black and brown object the size of his fist that looked a lot like a clam. “These are the underdogs of water quality,” he said. “And also, unfortunately, on their way to extinction.” Young is part of a team that is reintroducing the California floater mussel, a native freshwater mussel, and other native plants and animals, to Mountain Lake — a tiny 2,000-year-old natural lake located on the southern edges of San Francisco’s Presidio, nestled between the Presidio Golf Course, the Lake Street neighborhood and Park Presidio Boulevard. … ” Read more from KQED here: California floater mussels take fish for an epic joyride
Move over, San Andreas: There’s an ominous new fault in town: “U.S. route 395 is a geologic master class disguised as a road. It runs north from the arid outskirts of Los Angeles, carrying travelers up to Reno along the eastern flank of the Sierra Nevada. On the way, they pass the black cinder cones of Coso Volcanic Field and the eroded scars of a mighty 19th-century earthquake near Lone Pine. In winter, drivers might see steam rising from Hot Creek, where water boils up from an active supervolcano deep underground. About an hour from the Nevada border, Mono Lake appears, with its bulbous and surreal mineral formations known as tufa towers. Even for someone with no particular interest in rocks, these are captivating, otherworldly sights. But for James Faulds, Nevada’s state geologist, they are something more—clues to a great tectonic mystery unfolding in the American West. If he’s right, all of this, from the wastes of the Mojave Desert to the night-lit casinos of Reno, will someday be beachfront property. … ” Continue reading at WIRED Magazine here: Move over, San Andreas: There’s an ominous new fault in town
As snowmelt declines, farmers in western U.S. could be among the hardest hit: “As global temperatures continue to rise, farmers in the western United States who rely on snowmelt to water their crops could be one of the most severely affected agricultural communities in the world, according to a new study in the journal Nature Climate Change. Two of the most vulnerable regions to climate change will be the San Joaquin and Colorado river basins, both major producers of crops and livestock. ... ” Read more from Yale E360 here: As snowmelt declines, farmers in western U.S. could be among the hardest hit
With shrinking snowpack, drought predictability melting away: “On April 1, water managers across the West use the amount of snowpack present as a part of a simple equation to calculate the available water supply for a given region that year. Historically, this method has accurately predicted whether large areas of the western U.S. will experience drought and to what degree. But new research from CU Boulder suggests that during the 21st century, our ability to predict drought using snow will literally melt away. By mid-century, over two-thirds of western U.S. states that depend on snowmelt as a water source will see a significant reduction in their ability to predict seasonal drought using snowpack, according to the new study out today in Nature Climate Change. As we approach 2100, this area impacted by reduced drought prediction ability will increase to over 80%. … ” Read more from Science Daily here: With shrinking snowpack, drought predictability melting away
The tides they are a-changin’ — and it’s not just from climate change: “It was the muddy water that caught Stefan Talke’s eye. In the mid-2000s Talke was a postdoctoral scholar at Utrecht University, studying the Ems River that empties into the North Sea between Germany and the Netherlands. Decades earlier, engineers had begun dredging parts of the Ems so that newly built ships could navigate it from a shipyard upriver. But those changes also changed the rhythm in which tides ebbed and flowed into the river from the sea. Those shifting tides stirred up sediment from the river bottom and muddied its waters. Over the last 120 years the tidal range — the distance between high and low tide — has quintupled in the Ems estuary. … ” Read more from Knowable Magazine here: The tides they are a-changin’ — and it’s not just from climate change
Estuaries are warming at twice the rate of oceans and atmosphere: “Estuaries on the south-east coast of Australia are warming at twice the rate of oceans and the atmosphere, a new study has found. Researchers say the apparent accelerated impact from climate change on estuaries could adversely affect economic activity and ecological biodiversity in rivers and lakes worldwide. Dr Elliot Scanes from the University of Sydney said: “Our research shows that estuaries are particularly vulnerable to a warming environment. This is a concern not only for the marine and bird life that rely on them but the millions of people who depend on rivers, lakes and lagoons for their livelihoods around the world.” ... ” Read more from Science Daily here: Estuaries are warming at twice the rate of oceans and atmosphere
As sea levels rise, will drinking water supplies be at risk? “At the Delaware Memorial Bridge, about 35 miles southwest of Philadelphia, the tidal waters of the Delaware River estuary push upstream with every incoming tide but are opposed by the river’s downstream flow. For years, this balance has kept salty water well away from intakes that supply drinking water to millions of people in Philadelphia and southern New Jersey. With the so-called salt front in its normal range, some 40 miles downstream from the intakes, any threat to the region’s water supply has seemed distant. But the combination of sea level rise and the expectation of reduced downstream flow as a result of climate change-related droughts have raised new fears that the region’s biggest source of drinking water could at some point become contaminated with seawater. Other regions around the U.S. and the world, from Florida to Bangladesh, are facing similar threats. … ” Read more from Yale E360 here: As sea levels rise, will drinking water supplies be at risk?
Still Inspiring After 50 Years: Earth Day Images Then and Now: “Taking a step back and viewing the Earth from above not only can spark awe, it also can inspire change. Case in point—in 1969, Wisconsin Senator Gaylord Nelson witnessed an 800-square-mile oil spill in the Santa Barbara Channel as his plane flew over the disaster. What he saw inspired him to create the first Earth Day the following year. ... ” Read more and view satellite pictures at NOAA here: Still Inspiring After 50 Years: Earth Day Images Then and Now
Featured image credit: Dynamic Earth – Ocean Currents, by NASA via flickr: “Winds bear down on the ocean to create surface currents, seen here swirling off the coast of Florida in this NASA-created image, a still capture from a 4-minute excerpt of “Dynamic Earth: Exploring Earth’s Climate Engine,” a fulldome, high-resolution movie playing at planetariums around the world.”
About Science News and Reports: This weekly feature, posted every Thursday, is a collection of the latest scientific research and reports with a focus on relevant issues to the Delta and to California water, although other issues such as climate change are sometimes included. Do you have an item to be included here? Submissions of relevant research and other materials is welcome. Email Maven
